Issue #23507 config-api uses junit5 instead of junit4 - some tests were bit extended, some were deleted

diff --git a/nucleus/admin/config-api/pom.xml b/nucleus/admin/config-api/pom.xml
index 52cf426..25383db 100644
--- a/nucleus/admin/config-api/pom.xml
+++ b/nucleus/admin/config-api/pom.xml

@@ -95,6 +95,10 @@
             <scope>test</scope>
         </dependency>
         <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+        </dependency>
+        <dependency>
             <groupId>org.hamcrest</groupId>
             <artifactId>hamcrest</artifactId>
         </dependency>

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/config/modularity/tests/BasicModularityTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/config/modularity/tests/BasicModularityTest.java
index 7f2be56..33f079c 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/config/modularity/tests/BasicModularityTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/config/modularity/tests/BasicModularityTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2012, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -23,17 +24,21 @@
 import com.sun.enterprise.config.serverbeans.Config;
 import com.sun.enterprise.config.serverbeans.Domain;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
-import org.glassfish.hk2.api.ServiceLocator;
-import org.glassfish.hk2.runlevel.RunLevelController;
-import org.glassfish.server.ServerEnvironmentImpl;
-import org.glassfish.tests.utils.Utils;
-import org.junit.Test;
-import org.jvnet.hk2.config.ConfigBeanProxy;
-import org.jvnet.hk2.config.types.Property;
 
 import java.util.List;
 
-import static org.junit.Assert.*;
+import org.glassfish.api.admin.ServerEnvironment;
+import org.glassfish.hk2.api.ServiceLocator;
+import org.glassfish.hk2.runlevel.RunLevelController;
+import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigBeanProxy;
+import org.jvnet.hk2.config.types.Property;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * Testing Basic Functionality of Config Modularity API
@@ -42,7 +47,7 @@
  */
 public class BasicModularityTest extends ConfigApiTest {
 
-    private ServiceLocator habitat = Utils.instance.getHabitat(this);
+    private final ServiceLocator habitat = Utils.instance.getHabitat(this);
 
     ConfigModularityUtils configModularityUtils = habitat.getService(ConfigModularityUtils.class);
 
@@ -56,117 +61,140 @@
 
         // This part passes as the configuration for the class is present in the domain.xml
         Class clz = configModularityUtils.getClassForFullName(ConfigExtensionZero.class.getName());
-        assertNotNull("Cannot get config bean class using the class name", clz);
-        assertEquals("The mapped class is not the same as the provided class name", ConfigExtensionZero.class.getName(), clz.getName());
+        assertNotNull(clz, "Cannot get config bean class using the class name");
+        assertEquals(ConfigExtensionZero.class.getName(), clz.getName(), "The mapped class is not the same as the provided class name");
 
         // this part fails as the configuration is not present in domain.xml which was is a regression somewhere
         clz = configModularityUtils.getClassForFullName(ConfigExtensionTwo.class.getName());
-        assertNotNull("Cannot get config bean class using the class name", clz);
-        assertEquals("The mapped class is not the same as the provided class name", ConfigExtensionTwo.class.getName(), clz.getName());
+        assertNotNull(clz, "Cannot get config bean class using the class name");
+        assertEquals(ConfigExtensionTwo.class.getName(), clz.getName(), "The mapped class is not the same as the provided class name");
     }
 
     @Test
     public void locationTest() {
         String location = "domain/configs/config[$CURRENT_INSTANCE_CONFIG_NAME]/config-extension-one/property[prop.foo]";
         Class owningClass = configModularityUtils.getOwningClassForLocation(location);
-        assertNotNull("Cannot find owning class for: " + location, owningClass);
-        assertEquals("Cannot find the right owning class for location", Property.class.getName(), owningClass.getName());
+        assertNotNull(owningClass, "Cannot find owning class for: " + location);
+        assertEquals(Property.class.getName(), owningClass.getName(), "Cannot find the right owning class for location");
     }
 
     @Test
     public void owningObjectTest() {
         String location = "domain/configs/config[$CURRENT_INSTANCE_CONFIG_NAME]/config-extension-one/property[prop.foo]";
         ConfigBeanProxy obj = configModularityUtils.getOwningObject(location);
-        assertNotNull("Cannot find owning object for: " + location, obj);
-        assertEquals("Getting Owning object for location is not right", "prop.foo.value.custom", ((Property) obj).getValue());
+        assertNotNull(obj, "Cannot find owning object for: " + location);
+        assertEquals("prop.foo.value.custom", ((Property) obj).getValue(), "Getting Owning object for location is not right");
     }
 
     @Test
     public void moduleConfigurationXmlParserTest() {
         List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils.getDefaultConfigurations(SimpleExtensionTypeOne.class, "admin-");
-        assertEquals("Incorrect number of config bean configuration read ", 2, values.size());
+        assertEquals(2, values.size(), "Incorrect number of config bean configuration read ");
         ConfigCustomizationToken token = configModularityUtils.getDefaultConfigurations(SimpleExtensionTypeOne.class, "embedded-").get(0).getCustomizationTokens().get(0);
-        assertEquals("Customization Token reading broken ", "CUSTOM_TOKEN", token.getName());
-        assertEquals("Customization Token reading broken ", "token-default-value", token.getValue());
+        assertEquals("CUSTOM_TOKEN", token.getName(), "Customization Token reading broken ");
+        assertEquals("token-default-value", token.getValue(), "Customization Token reading broken ");
     }
 
 
     @Test
     public void serializeConfigBean() {
-        Config config = habitat.<Config>getService(Config.class, ServerEnvironmentImpl.DEFAULT_INSTANCE_NAME);
-        ConfigBeanProxy prox = (ConfigBeanProxy) config.getExtensionByType(ConfigExtensionZero.class);
+        Config config = habitat.<Config>getService(Config.class, ServerEnvironment.DEFAULT_INSTANCE_NAME);
+        ConfigBeanProxy prox = config.getExtensionByType(ConfigExtensionZero.class);
         String content = configModularityUtils.serializeConfigBean(prox);
-        assertEquals("Cannot serialize config beans properly", "<config-extension-zero dummy=\"dummy-value\"></config-extension-zero>", content);
+        assertEquals("<config-extension-zero dummy=\"dummy-value\"></config-extension-zero>", content,
+            "Cannot serialize config beans properly");
 
     }
 
     @Test
     public void serializeConfigBeanByType() {
         String content = configModularityUtils.serializeConfigBeanByType(ConfigExtensionOne.class);
-        assertEquals("Cannot serialize config beans from type", "<config-extension-one custom-token=\"${CUSTOM_TOKEN}\">\n" +
+        assertEquals("<config-extension-one custom-token=\"${CUSTOM_TOKEN}\">\n" +
                 "  <property name=\"prop.foo\" value=\"prop.foo.value.custom\"></property>\n" +
-                "</config-extension-one>", content);
+                "</config-extension-one>", content, "Cannot serialize config beans from type");
     }
 
 
     @Test
     public void testConfigExtensionPatternImpl() {
-        Config config = habitat.<Config>getService(Config.class, ServerEnvironmentImpl.DEFAULT_INSTANCE_NAME);
+        Config config = habitat.<Config>getService(Config.class, ServerEnvironment.DEFAULT_INSTANCE_NAME);
         SimpleConfigExtension simpleConfigExtension = config.getExtensionByType(SimpleConfigExtension.class);
         SimpleExtensionTypeTwo typeTwo = simpleConfigExtension.getExtensionByType(SimpleExtensionTypeTwo.class);
-        assertNotNull("cannot get extension using extensionmethod", typeTwo);
-        assertEquals("Retrieved extension is not from the right type... ", "attribute.two", typeTwo.getAttributeTwo());
+        assertNotNull(typeTwo, "cannot get extension using extensionmethod");
+        assertEquals("attribute.two", typeTwo.getAttributeTwo(), "Retrieved extension is not from the right type... ");
     }
 
     @Test
     public void testLoadingAndApplyingModuleConfigurationFile() {
-        Config config = habitat.<Config>getService(Config.class, ServerEnvironmentImpl.DEFAULT_INSTANCE_NAME);
+        Config config = habitat.<Config>getService(Config.class, ServerEnvironment.DEFAULT_INSTANCE_NAME);
         ConfigExtensionTwo ext = config.getExtensionByType(ConfigExtensionTwo.class);
-        assertEquals("The system property is overridden while it should have not", "user.customized.value", config.getSystemProperty("CUSTOM_TOKEN").getValue());
-        assertTrue("Failed to add the extension from module configuration file: ", config.checkIfExtensionExists(ConfigExtensionTwo.class));
+        assertNotNull(ext);
+        assertEquals("user.customized.value", config.getSystemProperty("CUSTOM_TOKEN").getValue(),
+            "The system property is overridden while it should have not");
+        assertTrue(config.checkIfExtensionExists(ConfigExtensionTwo.class),
+            "Failed to add the extension from module configuration file: ");
     }
 
 
     @Test
     public void testHasNoCustomization() {
-        Config config = habitat.<Config>getService(Config.class, ServerEnvironmentImpl.DEFAULT_INSTANCE_NAME);
-        assertNull("The @HasNocustomization annotation is broken", config.getExtensionByType(ConfigExtensionThree.class));
+        Config config = habitat.<Config>getService(Config.class, ServerEnvironment.DEFAULT_INSTANCE_NAME);
+        assertNull(config.getExtensionByType(ConfigExtensionThree.class), "The @HasNocustomization annotation is broken");
     }
 
     @Test
     public void getCurrentConfigurationForConfigBean() throws Exception {
-        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils.getDefaultConfigurations(SimpleExtensionTypeOne.class, "admin-");
-        com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue def = configModularityUtils.getDefaultConfigurations(SimpleExtensionTypeOne.class, "embedded-").get(0);
+        com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue def = configModularityUtils
+            .getDefaultConfigurations(SimpleExtensionTypeOne.class, "embedded-").get(0);
         SimpleExtensionTypeOne simple = configModularityUtils.getCurrentConfigBeanForDefaultValue(def);
-        assertNotNull("Cannot get config bean of a module based on the default module configuration information", simple);
+        assertNotNull(simple,
+            "Cannot get config bean of a module based on the default module configuration information");
     }
 
 
     @Test
     public void testLoadingAdminFile() throws Exception {
-        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils.getDefaultConfigurations(ConfigExtensionTwo.class, "admin");
-        assertEquals("Incorrect customization type loaded ", ConfigCustomizationToken.CustomizationType.FILE, values.get(0).getCustomizationTokens().get(0).getCustomizationType());
-        assertEquals("Incorrect customization details value ", FileTypeDetails.FileExistCondition.MUST_EXIST, ((FileTypeDetails) values.get(0).getCustomizationTokens().get(0).getTokenTypeDetails()).getExistCondition());
+        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils
+            .getDefaultConfigurations(ConfigExtensionTwo.class, "admin");
+        assertEquals(ConfigCustomizationToken.CustomizationType.FILE,
+            values.get(0).getCustomizationTokens().get(0).getCustomizationType(),
+            "Incorrect customization type loaded ");
+        assertEquals(FileTypeDetails.FileExistCondition.MUST_EXIST,
+            ((FileTypeDetails) values.get(0).getCustomizationTokens().get(0).getTokenTypeDetails()).getExistCondition(),
+            "Incorrect customization details value ");
     }
 
+
     @Test
     public void testLoadingEmbeddedFile() throws Exception {
-        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = values = configModularityUtils.getDefaultConfigurations(ConfigExtensionTwo.class, "embedded");
-        assertEquals("Incorrect customization type loaded ", ConfigCustomizationToken.CustomizationType.PORT, values.get(0).getCustomizationTokens().get(0).getCustomizationType());
-        assertEquals("Incorrect customization details value ", "1000", ((PortTypeDetails) values.get(0).getCustomizationTokens().get(0).getTokenTypeDetails()).getBaseOffset());
-        assertEquals("validation expression is returned incorrectly ", "[a-zA-Z0-9]+", values.get(0).getCustomizationTokens().get(0).getValidationExpression());
+        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils
+            .getDefaultConfigurations(ConfigExtensionTwo.class, "embedded");
+        assertEquals(ConfigCustomizationToken.CustomizationType.PORT,
+            values.get(0).getCustomizationTokens().get(0).getCustomizationType(),
+            "Incorrect customization type loaded ");
+        assertEquals("1000",
+            ((PortTypeDetails) values.get(0).getCustomizationTokens().get(0).getTokenTypeDetails()).getBaseOffset(),
+            "Incorrect customization details value ");
+        assertEquals("[a-zA-Z0-9]+", values.get(0).getCustomizationTokens().get(0).getValidationExpression(),
+            "validation expression is returned incorrectly ");
     }
 
+
     @Test
     public void testLoadingDefaultFile() throws Exception {
-        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils.getDefaultConfigurations(ConfigExtensionTwo.class, "non-existing-runtime-type");
-        assertEquals("validation expression is returned incorrectly ", ".*[0-9]{10}.*", values.get(0).getCustomizationTokens().get(0).getValidationExpression());
+        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils
+            .getDefaultConfigurations(ConfigExtensionTwo.class, "non-existing-runtime-type");
+        assertEquals(".*[0-9]{10}.*", values.get(0).getCustomizationTokens().get(0).getValidationExpression(),
+            "validation expression is returned incorrectly ");
     }
 
+
     @Test
     public void tesOnTheFlyConfigurationGenerationMethod() {
-        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils.getDefaultConfigurations(SimpleExtensionThree.class, "non-existing-runtime-type");
-        assertEquals("On the fly config generation/reading is broken", "<xml-doc></xml-doc>", values.get(0).getXmlConfiguration());
+        List<com.sun.enterprise.config.modularity.customization.ConfigBeanDefaultValue> values = configModularityUtils
+            .getDefaultConfigurations(SimpleExtensionThree.class, "non-existing-runtime-type");
+        assertEquals("<xml-doc></xml-doc>", values.get(0).getXmlConfiguration(),
+            "On the fly config generation/reading is broken");
     }
 
 
@@ -174,10 +202,10 @@
     public void testRanking() {
         Domain d = habitat.<Domain>getService(Domain.class);
         RankedConfigBean rankedConfigBean = d.getExtensionByType(RankedConfigBean.class);
-        assertEquals("invalid current value",  "simple-value-zero",rankedConfigBean.getSimpleAttribute());
+        assertEquals("simple-value-zero",rankedConfigBean.getSimpleAttribute(), "invalid current value");
         ensureRunLevel(4);
          rankedConfigBean = d.getExtensionByType(RankedConfigBean.class);
-        assertEquals("invalid current value", "simple-value-one", rankedConfigBean.getSimpleAttribute() );
+        assertEquals("simple-value-one", rankedConfigBean.getSimpleAttribute() , "invalid current value");
     }
 
     //TODO add more tests to cover token processing and i18n support

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AddPropertyTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AddPropertyTest.java
index 83a2c21..3b2190e 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AddPropertyTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AddPropertyTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -17,26 +18,26 @@
 package com.sun.enterprise.configapi.tests;
 
 import com.sun.enterprise.config.serverbeans.Domain;
-import org.jvnet.hk2.config.types.Property;
-import static org.junit.Assert.assertTrue;
-import org.junit.Test;
-import org.jvnet.hk2.config.Changed;
+
+import java.beans.PropertyChangeEvent;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigBean;
-import org.jvnet.hk2.config.ConfigBeanProxy;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.Dom;
-import org.jvnet.hk2.config.NotProcessed;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 import org.jvnet.hk2.config.TransactionListener;
 import org.jvnet.hk2.config.Transactions;
 import org.jvnet.hk2.config.UnprocessedChangeEvents;
+import org.jvnet.hk2.config.types.Property;
 
-import java.beans.PropertyChangeEvent;
-import java.beans.PropertyVetoException;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 /**
  * User: Jerome Dochez
@@ -45,20 +46,27 @@
  */
 public class AddPropertyTest extends ConfigApiTest {
 
+    private List<PropertyChangeEvent> events;
+
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    List<PropertyChangeEvent> events = null;
 
     @Test
     public void transactionEvents() throws TransactionFailure {
         final Domain domain = getHabitat().getService(Domain.class);
+        assertNotNull(domain);
         final TransactionListener listener = new TransactionListener() {
-                public void transactionCommited(List<PropertyChangeEvent> changes) {
-                    events = changes;
-                }
 
+            @Override
+            public void transactionCommited(List<PropertyChangeEvent> changes) {
+                events = changes;
+            }
+
+
+            @Override
             public void unprocessedTransactedEvents(List<UnprocessedChangeEvents> changes) {
             }
         };
@@ -68,28 +76,21 @@
         try {
 
             transactions.addTransactionsListener(listener);
-            assertTrue(domain!=null);
 
-            ConfigSupport.apply(new SingleConfigCode<Domain>() {
-
-                public Object run(Domain domain) throws PropertyVetoException, TransactionFailure {
-                    Property prop = domain.createChild(Property.class);
-                    domain.getProperty().add(prop);
-                    prop.setName("Jerome");
-                    prop.setValue("was here");
-                    return prop;
-                }
-            }, domain);
+            SingleConfigCode<Domain> configCode = (SingleConfigCode<Domain>) domain1 -> {
+                Property prop = domain1.createChild(Property.class);
+                domain1.getProperty().add(prop);
+                prop.setName("Jerome");
+                prop.setValue("was here");
+                return prop;
+            };
+            ConfigSupport.apply(configCode, domain);
             transactions.waitForDrain();
 
-            assertTrue(events!=null);
-            logger.fine("Number of events " + events.size());
-            assertTrue(events.size()==3);
-            for (PropertyChangeEvent event : events) {
-                logger.fine(event.toString());
-            }
+            assertNotNull(events);
+            assertThat(events, hasSize(3));
 
-            Map<String, String> configChanges = new HashMap<String, String>();
+            Map<String, String> configChanges = new HashMap<>();
             configChanges.put("name", "julien");
             configChanges.put("value", "petit clown");
             ConfigBean domainBean = (ConfigBean) Dom.unwrap(domain);
@@ -98,28 +99,8 @@
 
             transactions.waitForDrain();
 
-            assertTrue(events!=null);
-            logger.fine("Number of events " + events.size());
-            assertTrue(events.size()==3);
-            for (PropertyChangeEvent event : events) {
-                logger.fine(event.toString());
-            }
-
-            final UnprocessedChangeEvents unprocessed =
-                ConfigSupport.sortAndDispatch(events.toArray(new PropertyChangeEvent[0]), new Changed() {
-                /**
-                 * Notification of a change on a configuration object
-                 *
-                 * @param type            type of change : ADD mean the changedInstance was added to the parent
-                 *                        REMOVE means the changedInstance was removed from the parent, CHANGE means the
-                 *                        changedInstance has mutated.
-                 * @param changedType     type of the configuration object
-                 * @param changedInstance changed instance.
-                 */
-                public <T extends ConfigBeanProxy> NotProcessed changed(TYPE type, Class<T> changedType, T changedInstance) {
-                    return new NotProcessed("unimplemented by AddPropertyTest");
-                }
-            }, logger);
+            assertNotNull(events);
+            assertThat(events, hasSize(3));
         } finally {
             transactions.removeTransactionsListener(listener);
         }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ApplicationsTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ApplicationsTest.java
index e46b387..fa043b3 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ApplicationsTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ApplicationsTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,14 +17,23 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.junit.Test;
-import static org.junit.Assert.assertTrue;
-import org.glassfish.api.admin.config.ApplicationName;
-import org.jvnet.hk2.config.*;
-import com.sun.enterprise.config.serverbeans.*;
+import com.sun.enterprise.config.serverbeans.Application;
+import com.sun.enterprise.config.serverbeans.Applications;
 
 import java.util.List;
-import java.beans.*;
+
+import org.glassfish.api.admin.config.ApplicationName;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.SingleConfigCode;
+import org.jvnet.hk2.config.TransactionFailure;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.instanceOf;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * Applications related tests
@@ -31,7 +41,7 @@
  */
 public class ApplicationsTest extends ConfigApiTest {
 
-
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
@@ -39,48 +49,41 @@
     @Test
     public void appsExistTest() {
         Applications apps = getHabitat().getService(Applications.class);
-        assertTrue(apps!=null);
+        assertNotNull(apps);
+        assertThat(apps.getApplications(), hasSize(1));
     }
 
     @Test
     public void getModulesTest() {
         Applications apps = getHabitat().getService(Applications.class);
         List<ApplicationName> modules = apps.getModules();
-        for (ApplicationName module : modules) {
-            logger.fine("Module = " + module.getName());
-        }
-        assertTrue(modules!=null);
+        assertThat(modules, hasSize(1));
     }
 
     @Test
     public void getApplicationTest() {
         Applications apps = getHabitat().getService(Applications.class);
         Application app = apps.getApplication("simple");
-        assertTrue(app != null);
+        assertNotNull(app);
     }
 
     /**
      * Test which is expecting an UnsupportedOperationException since we are
      * operating on a copy list of the original getModules() list.
-     *
-     * @throws TransactionFailure
      */
-    @Test(expected = UnsupportedOperationException.class)
-    public void removalTest() throws Throwable {
-        Applications apps = getHabitat().getService(Applications.class);
-        try {
-            ConfigSupport.apply(new SingleConfigCode<Applications>() {
-                public Object run(Applications param) throws PropertyVetoException, TransactionFailure {
-                    List<Application> appList = param.getApplications();
-                    for (Application application : param.getApplicationsWithSnifferType("web")) {
-                        assertTrue(appList.remove(application));
-                    }
-                    return null;
-                }
-            }, apps);
-        } catch(TransactionFailure e) {
-            // good, an exception was thrown, hopfully the right one !
-            throw e.getCause();
-        }
+    @Test
+    public void removalTest() {
+        final Applications apps = getHabitat().getService(Applications.class);
+        final SingleConfigCode<Applications> configCode = param -> {
+            List<Application> appList = param.getApplications();
+            for (Application application : param.getApplicationsWithSnifferType("web")) {
+                assertTrue(appList.remove(application));
+            }
+            return null;
+        };
+        final TransactionFailure failure = assertThrows(TransactionFailure.class, () -> {
+            ConfigSupport.apply(configCode, apps);
+        });
+        assertThat(failure.getCause(), instanceOf(UnsupportedOperationException.class));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AttributeRemovalTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AttributeRemovalTest.java
index 59c5a27..db04480 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AttributeRemovalTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/AttributeRemovalTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,18 +17,21 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import com.sun.enterprise.config.serverbeans.Server;
-import org.junit.Test;
-import org.junit.Before;
-import org.jvnet.hk2.config.*;
-import org.glassfish.tests.utils.Utils;
 import com.sun.enterprise.config.serverbeans.HttpService;
+import com.sun.enterprise.config.serverbeans.Server;
 import com.sun.enterprise.config.serverbeans.VirtualServer;
 
-import java.beans.PropertyChangeEvent;
 import java.beans.PropertyVetoException;
-import java.util.List;
-import java.util.logging.Level;
+import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.SingleConfigCode;
+import org.jvnet.hk2.config.TransactionFailure;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * User: Jerome Dochez
@@ -36,6 +40,7 @@
  */
 public class AttributeRemovalTest extends ConfigApiTest {
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
@@ -44,66 +49,45 @@
     public void removeAttributeTest() throws TransactionFailure {
         HttpService httpService = Utils.instance.getHabitat(this).getService(HttpService.class);
         VirtualServer vs = httpService.getVirtualServerByName("server");
-        ConfigSupport.apply(new SingleConfigCode<VirtualServer>() {
+        SingleConfigCode<VirtualServer> configCodeWebModule = virtualServer -> {
+            virtualServer.setDefaultWebModule("/context/bar");
+            return null;
+        };
+        ConfigSupport.apply(configCodeWebModule, vs);
+        assertNotNull(vs.getDefaultWebModule());
 
-            public Object run(VirtualServer param) throws PropertyVetoException, TransactionFailure {
-                param.setDefaultWebModule("/context/bar");
-                return null;
-            }
-        }, vs);
-
-        // ensure it's here
-        org.junit.Assert.assertNotNull(vs.getDefaultWebModule());
-
-        ConfigSupport.apply(new SingleConfigCode<VirtualServer>() {
-
-            public Object run(VirtualServer param) throws PropertyVetoException, TransactionFailure {
-                param.setDefaultWebModule(null);
-                return null;
-            }
-        }, vs);
-
-        // ensure it's removed
-        org.junit.Assert.assertNull(vs.getDefaultWebModule());
-    }
-
-    @Test(expected=PropertyVetoException.class)
-    public void readOnlyRemovalTest() throws TransactionFailure , PropertyVetoException{
-        Server server = getHabitat().getService(Server.class);
-        logger.fine("config-ref is " + server.getConfigRef());
-        try {
-            server.setConfigRef(null);
-        } catch (PropertyVetoException e) {
-            if (logger.isLoggable(Level.FINE))
-                e.printStackTrace();
-            throw e;
-        }
+        SingleConfigCode<VirtualServer> configCodeNullWebModule = virtualServer -> {
+            virtualServer.setDefaultWebModule(null);
+            return null;
+        };
+        ConfigSupport.apply(configCodeNullWebModule, vs);
+        assertNull(vs.getDefaultWebModule());
     }
 
     @Test
+    public void readOnlyRemovalTest(){
+        Server server = getHabitat().getService(Server.class);
+        logger.fine("config-ref is " + server.getConfigRef());
+        assertThrows(PropertyVetoException.class, () -> server.setConfigRef(null));
+    }
+
+    @Test
+    @SuppressWarnings("deprecation")
     public void deprecatedWrite() throws TransactionFailure {
         final Server server = getHabitat().getService(Server.class);
         final String value = server.getNodeRef();
-        logger.fine("node-ref is " + server.getNodeRef());
-        ConfigSupport.apply(new SingleConfigCode<Server>() {
-            @Override
-            public Object run(Server s) throws PropertyVetoException, TransactionFailure {
-                s.setNodeAgentRef(value);
-                return null;
-            }
-        }, server);
-        logger.fine("node-agent-ref is " + server.getNodeAgentRef());
-        // restore
-        ConfigSupport.apply(new SingleConfigCode<Server>() {
-            @Override
-            public Object run(Server s) throws PropertyVetoException, TransactionFailure {
-                s.setNodeAgentRef(null);
-                return null;
-            }
-        }, server);
-        logger.fine("after, node-agent-ref is " + server.getNodeAgentRef());
+        final SingleConfigCode<Server> configCode = virtualServer -> {
+            virtualServer.setNodeAgentRef(null);
+            return null;
+        };
+        ConfigSupport.apply(configCode, server);
+        assertNull(server.getNodeRef());
 
+        SingleConfigCode<Server> restoreConfig = virtualServer -> {
+            virtualServer.setNodeAgentRef(value);
+            return null;
+        };
+        ConfigSupport.apply(restoreConfig, server);
+        assertEquals(value, server.getNodeAgentRef());
     }
-
-
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/CollectionsAccessTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/CollectionsAccessTest.java
index 59345e9..496921f 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/CollectionsAccessTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/CollectionsAccessTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,17 +17,19 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.junit.Test;
-import static org.junit.Assert.*;
-import org.jvnet.hk2.config.TransactionFailure;
-import org.jvnet.hk2.config.ConfigSupport;
-import org.jvnet.hk2.config.SingleConfigCode;
-import org.glassfish.api.admin.config.ApplicationName;
-import com.sun.enterprise.config.serverbeans.Applications;
 import com.sun.enterprise.config.serverbeans.Application;
+import com.sun.enterprise.config.serverbeans.Applications;
 
 import java.util.List;
-import java.beans.PropertyVetoException;
+
+import org.glassfish.api.admin.config.ApplicationName;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.SingleConfigCode;
+import org.jvnet.hk2.config.TransactionFailure;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * User: Jerome Dochez
@@ -36,48 +39,46 @@
 public class CollectionsAccessTest extends ConfigApiTest  {
 
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Test(expected=IllegalStateException.class)
-    public void unprotectedAccess() throws IllegalStateException {
+    @Test
+    public void unprotectedAccess() {
         Applications apps = getHabitat().getService(Applications.class);
-        assertTrue(apps!=null);
-        apps.getModules().add(null);
+        assertNotNull(apps);
+        assertThrows(IllegalStateException.class, () -> apps.getModules().add(null));
     }
 
-    @Test(expected= TransactionFailure.class)
+    @Test
     public void semiProtectedTest() throws TransactionFailure {
         final Applications apps = getHabitat().getService(Applications.class);
-        assertTrue(apps!=null);
-        ConfigSupport.apply(new SingleConfigCode<Applications>() {
-            public Object run(Applications param) throws PropertyVetoException, TransactionFailure {
-                // this is the bug, we should not get the list from apps but from param.
-                List<ApplicationName> modules = apps.getModules();
-                Application m = param.createChild(Application.class);
-                modules.add(m); // should throw an exception
-                return m;
-            }
-        }, apps);
+        assertNotNull(apps);
+        SingleConfigCode<Applications> configCode = proxy -> {
+            List<ApplicationName> modules = proxy.getModules();
+            Application m = proxy.createChild(Application.class);
+            modules.add(m);
+            return m;
+        };
+        assertThrows(TransactionFailure.class, () -> ConfigSupport.apply(configCode, apps));
     }
 
     @Test
     public void protectedTest() throws TransactionFailure {
         final Applications apps = getHabitat().getService(Applications.class);
-        assertTrue(apps!=null);
-        ConfigSupport.apply(new SingleConfigCode<Applications>() {
-            public Object run(Applications param) throws PropertyVetoException, TransactionFailure {
-                List<ApplicationName> modules = param.getModules();
-                Application m = param.createChild(Application.class);
-                m.setName( "ejb-test" );
-                m.setLocation("test-location");
-                m.setObjectType("ejb");
-                modules.add(m);
-                modules.remove(m);
-                return m;
-            }
-        }, apps);
+        assertNotNull(apps);
+        SingleConfigCode<Applications> configCode = proxy -> {
+            List<ApplicationName> modules = proxy.getModules();
+            Application m = proxy.createChild(Application.class);
+            m.setName( "ejb-test" );
+            m.setLocation("test-location");
+            m.setObjectType("ejb");
+            modules.add(m);
+            modules.remove(m);
+            return m;
+        };
+        ConfigSupport.apply(configCode, apps);
     }
 }
 

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigApiTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigApiTest.java
index 8a0e9c4..29a21f2 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigApiTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigApiTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -21,10 +22,11 @@
 import org.glassfish.config.support.GlassFishDocument;
 import org.glassfish.hk2.api.ActiveDescriptor;
 import org.glassfish.hk2.api.ServiceLocator;
-import org.glassfish.hk2.utilities.BuilderHelper;
 import org.glassfish.hk2.utilities.ServiceLocatorUtilities;
 import org.jvnet.hk2.config.DomDocument;
 
+import static org.glassfish.hk2.utilities.BuilderHelper.createConstantDescriptor;
+
 import java.util.concurrent.Executors;
 import java.util.concurrent.ThreadFactory;
 import org.glassfish.api.admin.ServerEnvironment;
@@ -39,36 +41,39 @@
     @Override
     public DomDocument getDocument(ServiceLocator habitat) {
         DomDocument doc = habitat.getService(GlassFishDocument.class);
-        if (doc==null) {
+        if (doc == null) {
             return new GlassFishDocument(habitat, Executors.newCachedThreadPool(new ThreadFactory() {
 
-                        public Thread newThread(Runnable r) {
-                            Thread t = Executors.defaultThreadFactory().newThread(r);
-                            t.setDaemon(true);
-                            return t;
-                        }
+                @Override
+                public Thread newThread(Runnable r) {
+                    Thread t = Executors.defaultThreadFactory().newThread(r);
+                    t.setDaemon(true);
+                    return t;
+                }
 
-                    }));
+            }));
         }
         return doc;
     }
 
+
     @Override
-    public void decorate(ServiceLocator habitat) {
-        Server server = habitat.getService(Server.class, "server");
-        if (server != null) {
-            ActiveDescriptor<Server> serverDescriptor = BuilderHelper.createConstantDescriptor(server,
-                    ServerEnvironment.DEFAULT_INSTANCE_NAME, Server.class);
-            ServiceLocatorUtilities.addOneDescriptor(habitat, serverDescriptor);
+    public void decorate(ServiceLocator locator) {
+        Server server = locator.getService(Server.class, "server");
+        if (server == null) {
+            return;
+        }
+        ActiveDescriptor<Server> serverDescriptor
+            = createConstantDescriptor(server, ServerEnvironment.DEFAULT_INSTANCE_NAME, Server.class);
+        ServiceLocatorUtilities.addOneDescriptor(locator, serverDescriptor);
 
-            server.getConfig().addIndex(habitat, ServerEnvironment.DEFAULT_INSTANCE_NAME);
+        server.getConfig().addIndex(locator, ServerEnvironment.DEFAULT_INSTANCE_NAME);
 
-            Cluster c = server.getCluster();
-            if (c != null) {
-                ActiveDescriptor<Cluster> clusterDescriptor = BuilderHelper.createConstantDescriptor(c,
-                        ServerEnvironment.DEFAULT_INSTANCE_NAME, Cluster.class);
-                ServiceLocatorUtilities.addOneDescriptor(habitat, clusterDescriptor);
-            }
+        Cluster c = server.getCluster();
+        if (c != null) {
+            ActiveDescriptor<Cluster> clusterDescriptor
+                = createConstantDescriptor(c, ServerEnvironment.DEFAULT_INSTANCE_NAME, Cluster.class);
+            ServiceLocatorUtilities.addOneDescriptor(locator, clusterDescriptor);
         }
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigListenerTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigListenerTest.java
index 171b7c4..0121998 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigListenerTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigListenerTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,129 +17,112 @@
 
 package com.sun.enterprise.configapi.tests;
 
+import com.sun.enterprise.configapi.tests.example.HttpListenerContainer;
+
+import org.glassfish.config.support.ConfigConfigBeanListener;
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.hk2.api.DynamicConfiguration;
 import org.glassfish.hk2.api.DynamicConfigurationService;
 import org.glassfish.hk2.api.ServiceHandle;
 import org.glassfish.hk2.api.ServiceLocator;
-
-import org.glassfish.config.support.ConfigConfigBeanListener;
 import org.glassfish.tests.utils.Utils;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-
-import org.junit.Assert;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.ObservableBean;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 import org.jvnet.hk2.config.Transactions;
 
-import com.sun.enterprise.config.serverbeans.Config;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * Simple ConfigListener tests
  */
 public class ConfigListenerTest extends ConfigApiTest {
 
-    ServiceLocator habitat;
+    private static final SingleConfigCode<NetworkListener> configCodeRestore = param -> {
+        param.setPort("8080");
+        return null;
+    };
+
+    private ServiceLocator habitat;
+    private Transactions transactions;
+    private HttpListenerContainer container;
+
 
     @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
         habitat = Utils.instance.getHabitat(this);
 
         // make sure the ConfigConfigListener exists
         ServiceHandle<ConfigConfigBeanListener> i = habitat.getServiceHandle(ConfigConfigBeanListener.class);
         ConfigConfigBeanListener ccbl = i.getService();
-        assertTrue(ccbl != null);
+        assertNotNull(ccbl);
+        transactions = getHabitat().getService(Transactions.class);
+        container = registerAndCreateHttpListenerContainer(habitat);
     }
 
-    private HttpListenerContainer registerAndCreateHttpListenerContainer(ServiceLocator locator) {
-        HttpListenerContainer retVal = locator.getService(HttpListenerContainer.class);
-        if (retVal != null) return retVal;
 
-        DynamicConfigurationService dcs = locator.getService(DynamicConfigurationService.class);
-        Assert.assertNotNull(dcs);
-
-        DynamicConfiguration config = dcs.createDynamicConfiguration();
-
-        config.addActiveDescriptor(HttpListenerContainer.class);
-
-        config.commit();
-
-        return locator.getService(HttpListenerContainer.class);
+    @AfterEach
+    public void reset() throws TransactionFailure {
+        ConfigSupport.apply(configCodeRestore, container.httpListener);
+        assertEquals("8080", container.httpListener.getPort());
     }
 
-
     @Test
     public void changedTest() throws TransactionFailure {
-
-        Transactions transactions = getHabitat().getService(Transactions.class);
-
-        HttpListenerContainer container = registerAndCreateHttpListenerContainer(habitat);
-
-        ConfigSupport.apply(new SingleConfigCode<NetworkListener>() {
-
-            @Override
-            public Object run(NetworkListener param) {
-                param.setPort("8989");
-                return null;
-            }
-        }, container.httpListener);
+        SingleConfigCode<NetworkListener> configCode = listener -> {
+            listener.setPort("8989");
+            return null;
+        };
+        ConfigSupport.apply(configCode, container.httpListener);
+        assertEquals("8989", container.httpListener.getPort());
 
         transactions.waitForDrain();
         assertTrue(container.received);
         ObservableBean bean = (ObservableBean) ConfigSupport.getImpl(container.httpListener);
         bean.removeListener(container);
-
-        // put back the right values in the domain to avoid test collisions
-        ConfigSupport.apply(new SingleConfigCode<NetworkListener>() {
-
-            @Override
-            public Object run(NetworkListener param) {
-                param.setPort("8080");
-                return null;
-            }
-        }, container.httpListener);
     }
 
     @Test
     public void removeListenerTest() throws TransactionFailure {
-
-        Transactions transactions = getHabitat().getService(Transactions.class);
-
-        HttpListenerContainer container = registerAndCreateHttpListenerContainer(habitat);
-
         ObservableBean bean = (ObservableBean) ConfigSupport.getImpl(container.httpListener);
         bean.removeListener(container);
 
-        ConfigSupport.apply(new SingleConfigCode<NetworkListener>() {
-
-            @Override
-            public Object run(NetworkListener param) {
-                param.setPort("8989");
-                return null;
-            }
-        }, container.httpListener);
+        SingleConfigCode<NetworkListener> configCode = listener -> {
+            listener.setPort("8989");
+            return null;
+        };
+        ConfigSupport.apply(configCode, container.httpListener);
 
         transactions.waitForDrain();
         assertFalse(container.received);
+    }
 
-        // put back the right values in the domain to avoid test collisions
-        ConfigSupport.apply(new SingleConfigCode<NetworkListener>() {
 
-            @Override
-            public Object run(NetworkListener param) {
-                param.setPort("8080");
-                return null;
-            }
-        }, container.httpListener);
+    private HttpListenerContainer registerAndCreateHttpListenerContainer(ServiceLocator locator) {
+        HttpListenerContainer retVal = locator.getService(HttpListenerContainer.class);
+        if (retVal != null) {
+            return retVal;
+        }
+
+        DynamicConfigurationService dcs = locator.getService(DynamicConfigurationService.class);
+        assertNotNull(dcs);
+
+        DynamicConfiguration config = dcs.createDynamicConfiguration();
+        config.addActiveDescriptor(HttpListenerContainer.class);
+        config.commit();
+
+        return locator.getService(HttpListenerContainer.class);
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigPersistence.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigPersistence.java
index e9dfe44..1026c91 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigPersistence.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ConfigPersistence.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,8 +17,6 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import static org.junit.Assert.assertTrue;
-
 import java.beans.PropertyChangeEvent;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
@@ -29,11 +28,10 @@
 
 import org.glassfish.config.support.ConfigurationPersistence;
 import org.glassfish.tests.utils.Utils;
-import org.junit.After;
-import org.junit.Test;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.DomDocument;
 import org.jvnet.hk2.config.IndentingXMLStreamWriter;
-import org.jvnet.hk2.config.TransactionFailure;
 import org.jvnet.hk2.config.TransactionListener;
 import org.jvnet.hk2.config.Transactions;
 import org.jvnet.hk2.config.UnprocessedChangeEvents;
@@ -45,67 +43,62 @@
  */
 public abstract class ConfigPersistence extends ConfigApiTest {
 
-    @After
+    public abstract void doTest() throws Exception;
+
+    public abstract void assertResult(String resultingXml);
+
+    @AfterEach
     public void tearDown() {
-            Utils.instance.shutdownServiceLocator(this);
+        Utils.instance.shutdownServiceLocator(this);
     }
 
-    @Test
-    public void test() throws TransactionFailure {
 
+    @Test
+    public void test() throws Exception {
         final DomDocument document = getDocument(getHabitat());
 
         final ByteArrayOutputStream baos = new ByteArrayOutputStream();
         baos.reset();
 
-        final ConfigurationPersistence testPersistence =  new ConfigurationPersistence() {
-            public void save(DomDocument doc) throws IOException, XMLStreamException {
-                XMLOutputFactory factory = XMLOutputFactory.newInstance();
-                XMLStreamWriter writer = factory.createXMLStreamWriter(baos);
+        final ConfigurationPersistence testPersistence = doc -> {
+            XMLOutputFactory factory = XMLOutputFactory.newInstance();
+            XMLStreamWriter writer = factory.createXMLStreamWriter(baos);
+            try {
                 doc.writeTo(new IndentingXMLStreamWriter(writer));
+            } finally {
                 writer.close();
             }
         };
 
         TransactionListener testListener = new TransactionListener() {
+
+            @Override
             public void transactionCommited(List<PropertyChangeEvent> changes) {
                 try {
                     testPersistence.save(document);
-                } catch (IOException e) {
-                    e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
-                } catch (XMLStreamException e) {
-                    e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
+                } catch (IOException | XMLStreamException e) {
+                    e.printStackTrace();
                 }
             }
 
-            public void unprocessedTransactedEvents(List<UnprocessedChangeEvents> changes) {
 
+            @Override
+            public void unprocessedTransactedEvents(List<UnprocessedChangeEvents> changes) {
             }
         };
         Transactions transactions = getHabitat().getService(Transactions.class);
 
         try {
             transactions.addTransactionsListener(testListener);
-
             doTest();
-        } catch(TransactionFailure f) {
-            f.printStackTrace();
-            throw f;
-
         } finally {
             transactions.waitForDrain();
             transactions.removeTransactionsListener(testListener);
         }
 
         // now check if we persisted correctly...
-
         final String resultingXml = baos.toString();
-
         logger.fine(resultingXml);
-        assertTrue("assertResult from " + getClass().getName() + " was false from " + resultingXml, assertResult(resultingXml));
+        assertResult(resultingXml);
     }
-
-    public abstract void doTest() throws TransactionFailure;
-
-    public abstract boolean assertResult(String resultingXml);
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DeepCopyTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DeepCopyTest.java
index 107736c..ab933c6 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DeepCopyTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DeepCopyTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2012, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -18,19 +19,27 @@
 
 import com.sun.enterprise.config.serverbeans.Config;
 import com.sun.enterprise.config.serverbeans.Configs;
-import org.glassfish.config.support.ConfigurationPersistence;
-import org.junit.Assert;
-import org.junit.Test;
-import org.jvnet.hk2.config.*;
+
+import java.io.ByteArrayOutputStream;
+import java.util.logging.Level;
 
 import javax.xml.stream.XMLOutputFactory;
-import javax.xml.stream.XMLStreamException;
 import javax.xml.stream.XMLStreamWriter;
-import java.beans.PropertyVetoException;
-import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.io.OutputStream;
-import java.util.logging.Level;
+
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigBeanProxy;
+import org.jvnet.hk2.config.ConfigModel;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
+import org.jvnet.hk2.config.DomDocument;
+import org.jvnet.hk2.config.IndentingXMLStreamWriter;
+import org.jvnet.hk2.config.SingleConfigCode;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.stringContainsInOrder;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * Test the deepCopy feature of ConfigBeans.
@@ -39,6 +48,10 @@
  */
 public class DeepCopyTest extends ConfigApiTest {
 
+    private final DomDocument document = getDocument(getHabitat());
+
+
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
@@ -46,57 +59,42 @@
     @Test
     public void configCopy() throws Exception {
         final Config config = getHabitat().getService(Config.class);
-        Assert.assertNotNull(config);
+        assertNotNull(config);
         String configName = config.getName();
-        final Config newConfig = (Config) ConfigSupport.apply(new SingleConfigCode<ConfigBeanProxy>() {
-            @Override
-            public Object run(ConfigBeanProxy parent) throws PropertyVetoException, TransactionFailure {
-                return config.deepCopy(parent);
-            }
-        }, config.getParent());
-        Assert.assertNotNull(newConfig);
-        try {
-            newConfig.setName("some-config");
-        } catch(Exception e) {
-            // I was expecting this...
-        }
-        ConfigSupport.apply(new SingleConfigCode<Config>() {
-            @Override
-            public Object run(Config wConfig) throws PropertyVetoException, TransactionFailure {
-                wConfig.setName("some-config");
-                return null;
-            }
-        }, newConfig);
-        Assert.assertEquals(newConfig.getName(), "some-config");
-        Assert.assertEquals(config.getName(), configName);
+        final Config newConfig = (Config) ConfigSupport.apply(parent -> config.deepCopy(parent), config.getParent());
+        assertNotNull(newConfig);
+        assertThrows(IllegalStateException.class, () -> newConfig.setName("some-config"));
+        SingleConfigCode<Config> configCode = cfg -> {
+            cfg.setName("some-config");
+            return null;
+        };
+        ConfigSupport.apply(configCode, newConfig);
+        assertEquals("some-config", newConfig.getName());
+        assertEquals(configName, config.getName());
 
         // add it the parent
-        ConfigSupport.apply(new SingleConfigCode<Configs>() {
-            @Override
-            public Object run(Configs wConfigs) throws PropertyVetoException, TransactionFailure {
-                wConfigs.getConfig().add(newConfig);
-                return null;
-            }
-        }, getHabitat().<Configs>getService(Configs.class));
-        String resultingXML = save(document).toString();
-        Assert.assertTrue("Expecting some-config, got " + resultingXML, resultingXML.contains("some-config"));
+        SingleConfigCode<Configs> configCodeParent = configs -> {
+            configs.getConfig().add(newConfig);
+            return null;
+        };
+        ConfigSupport.apply(configCodeParent, getHabitat().<Configs>getService(Configs.class));
+        String resultingXML = save(document);
+        assertThat("Expecting some-config, got " + resultingXML, resultingXML, stringContainsInOrder("some-config"));
     }
 
     @Test
     public void parentingTest() throws Exception {
 
         final Config config = getHabitat().getService(Config.class);
-        Assert.assertNotNull(config);
-        String configName = config.getName();
-        final Config newConfig = (Config) ConfigSupport.apply(new SingleConfigCode<ConfigBeanProxy>() {
-            @Override
-            public Object run(ConfigBeanProxy parent) throws PropertyVetoException, TransactionFailure {
-                Config newConfig = (Config) config.deepCopy(parent);
-                newConfig.setName("cloned-config");
-                return newConfig;
-            }
-        }, config.getParent());
-        Assert.assertNotNull(newConfig);
+        assertNotNull(config);
+        assertEquals("server-config", config.getName());
+        SingleConfigCode<ConfigBeanProxy> configCode = configProxy -> {
+            Config newConfig1 = (Config) config.deepCopy(configProxy);
+            newConfig1.setName("cloned-config");
+            return newConfig1;
+        };
+        final Config newConfig = (Config) ConfigSupport.apply(configCode, config.getParent());
+        assertNotNull(newConfig);
 
         // now let's check the parents are correct.
         Dom original = Dom.unwrap(config);
@@ -112,48 +110,56 @@
     private void assertTypes(Dom original, Dom cloned) {
         logger.info(original.model.getTagName()+":" + original.getKey() + ":" + original.getClass().getSimpleName() +
                 " and " + cloned.model.getTagName()+":" + cloned.getKey() + ":" + cloned.getClass().getSimpleName());
-        Assert.assertEquals(original.getClass(), cloned.getClass());
+        assertEquals(original.getClass(), cloned.getClass());
         for (String elementName : original.getElementNames()) {
             ConfigModel.Property property = original.model.getElement(elementName);
-            if (property != null && property.isLeaf()) continue;
+            if (property != null && property.isLeaf()) {
+                continue;
+            }
             Dom originalChild = original.element(elementName);
             Dom clonedChild = cloned.element(elementName);
-            if (originalChild==null && clonedChild==null) continue;
-            Assert.assertNotNull(originalChild);
-            Assert.assertNotNull(clonedChild);
+            if (originalChild==null && clonedChild==null) {
+                continue;
+            }
+            assertNotNull(originalChild);
+            assertNotNull(clonedChild);
             assertTypes(originalChild, clonedChild);
         }
     }
 
     private void assertParenting(Dom dom) {
-
         for (String elementName : dom.model.getElementNames()) {
             ConfigModel.Property property = dom.model.getElement(elementName);
-            if (property.isLeaf()) continue;
+            if (property.isLeaf()) {
+                continue;
+            }
             Dom child = dom.element(elementName);
-            if (child==null) continue;
+            if (child==null) {
+                continue;
+            }
             if (logger.isLoggable(Level.FINE)) {
-                logger.fine("Parent of " + child.model.targetTypeName + ":" + child.getKey() + " is " + child.parent().getKey() + " while I am " + dom.getKey());
+                logger.fine("Parent of " + child.model.targetTypeName + ":" + child.getKey() + " is "
+                    + child.parent().getKey() + " while I am " + dom.getKey());
             }
             logger.info("Parent of " + child.model.targetTypeName + ":" + child.getKey() + " is " +
                     child.parent().model.targetTypeName + ":" + child.parent().getKey() + " while I am " +
                     dom.model.targetTypeName + ":" + dom.getKey());
 
-            Assert.assertEquals(dom, child.parent());
+            assertEquals(dom, child.parent());
             assertParenting(child);
         }
     }
 
-    final DomDocument document = getDocument(getHabitat());
-
-    public OutputStream save(DomDocument doc) throws IOException, XMLStreamException {
-        final ByteArrayOutputStream outStream = new ByteArrayOutputStream();
-        outStream.reset();
-
-        XMLOutputFactory factory = XMLOutputFactory.newInstance();
-        XMLStreamWriter writer = factory.createXMLStreamWriter(outStream);
-        doc.writeTo(new IndentingXMLStreamWriter(writer));
-        writer.close();
-        return outStream;
+    private String save(DomDocument doc) throws Exception {
+        try (ByteArrayOutputStream outStream = new ByteArrayOutputStream()) {
+            XMLOutputFactory factory = XMLOutputFactory.newInstance();
+            XMLStreamWriter writer = factory.createXMLStreamWriter(outStream);
+            try {
+                doc.writeTo(new IndentingXMLStreamWriter(writer));
+            } finally {
+                writer.close();
+            }
+            return outStream.toString();
+        }
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DefaultValueTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DefaultValueTest.java
index bcaf04e..5b212e6 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DefaultValueTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DefaultValueTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,43 +17,44 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.glassfish.grizzly.config.dom.*;
-import static org.junit.Assert.assertEquals;
-import org.junit.Before;
-import org.junit.Test;
+import org.glassfish.grizzly.config.dom.Http;
+import org.glassfish.grizzly.config.dom.NetworkListener;
+import org.glassfish.grizzly.config.dom.NetworkListeners;
+import org.glassfish.grizzly.config.dom.Protocol;
+import org.glassfish.grizzly.config.dom.Protocols;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.Attribute;
 import org.jvnet.hk2.config.Dom;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 /**
  * Test attribute and raw attribute access *
  */
 public class DefaultValueTest extends ConfigApiTest {
 
-    NetworkListener listener;
+    private NetworkListener listener;
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
         NetworkListeners httpService = getHabitat().getService(NetworkListeners.class);
         listener = httpService.getNetworkListener().get(0);
-
     }
 
     @Test
     public void rawAttributeTest() throws NoSuchMethodException {
-
         String address = listener.getAddress();
-
         Dom raw = Dom.unwrap(listener);
         Attribute attr = raw.getProxyType().getMethod("getAddress").getAnnotation(Attribute.class);
-        assertEquals(attr.defaultValue(), address);
-
-        assertEquals(raw.attribute("address"), address);
-        assertEquals(raw.rawAttribute("address"), address);
-
+        assertEquals(address, attr.defaultValue());
+        assertEquals(address, raw.attribute("address"));
+        assertEquals(address, raw.rawAttribute("address"));
     }
 
     @Test
@@ -60,9 +62,7 @@
         Protocols protocols = getHabitat().getService(Protocols.class);
         for (Protocol protocol : protocols.getProtocol()) {
             Http http = protocol.getHttp();
-            System.out.println(http.getCompressableMimeType());
+            assertEquals(Http.COMPRESSABLE_MIME_TYPE, http.getCompressableMimeType());
         }
-
     }
-
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectAccessTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectAccessTest.java
index 6680ae5..95f599d 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectAccessTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectAccessTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -24,8 +25,12 @@
 import org.glassfish.tests.utils.Utils;
 import org.jvnet.hk2.config.ConfigBean;
 import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
 import org.jvnet.hk2.config.TransactionFailure;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.stringContainsInOrder;
+
 import java.util.HashMap;
 import java.util.Map;
 
@@ -36,7 +41,7 @@
  */
 public class DirectAccessTest extends ConfigPersistence {
 
-    ServiceLocator habitat = Utils.instance.getHabitat(this);
+    private final ServiceLocator locator = Utils.instance.getHabitat(this);
 
     /**
      * Returns the file name without the .xml extension to load the test configuration
@@ -44,6 +49,7 @@
      *
      * @return the configuration file name
      */
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
@@ -51,42 +57,43 @@
 
     @Override
     public ServiceLocator getBaseServiceLocator() {
-        return habitat;
+        return locator;
     }
 
+
     @Override
     public ServiceLocator getHabitat() {
-            return getBaseServiceLocator();
+        return getBaseServiceLocator();
     }
 
+
+    @Override
     public void doTest() throws TransactionFailure {
-        NetworkConfig networkConfig = habitat.getService(NetworkConfig.class);
-        final NetworkListener listener = networkConfig.getNetworkListeners()
-            .getNetworkListener().get(0);
+        NetworkConfig networkConfig = locator.getService(NetworkConfig.class);
+        final NetworkListener listener = networkConfig.getNetworkListeners().getNetworkListener().get(0);
         final Http http = listener.findHttpProtocol().getHttp();
-        ConfigBean config = (ConfigBean) ConfigBean.unwrap(http.getFileCache());
-        ConfigBean config2 = (ConfigBean) ConfigBean.unwrap(http);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
+        ConfigBean config = (ConfigBean) Dom.unwrap(http.getFileCache());
+        ConfigBean config2 = (ConfigBean) Dom.unwrap(http);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
         configChanges.put("max-age-seconds", "12543");
         configChanges.put("max-cache-size-bytes", "1200");
-        Map<String, String> config2Changes = new HashMap<String, String>();
+        Map<String, String> config2Changes = new HashMap<>();
         config2Changes.put("version", "12351");
         changes.put(config, configChanges);
         changes.put(config2, config2Changes);
 
-        JavaConfig javaConfig = habitat.getService(JavaConfig.class);
-        ConfigBean javaConfigBean = (ConfigBean) ConfigBean.unwrap(javaConfig);
-        Map<String, String> javaConfigChanges = new HashMap<String, String>();
+        JavaConfig javaConfig = locator.getService(JavaConfig.class);
+        ConfigBean javaConfigBean = (ConfigBean) Dom.unwrap(javaConfig);
+        Map<String, String> javaConfigChanges = new HashMap<>();
         javaConfigChanges.put("jvm-options", "-XFooBar=false");
         changes.put(javaConfigBean, javaConfigChanges);
 
         getHabitat().<ConfigSupport>getService(ConfigSupport.class).apply(changes);
     }
 
-    public boolean assertResult(String s) {
-        return s.contains("max-age-seconds=\"12543\"")
-            && s.contains("version=\"12351\"")
-            && s.contains("-XFooBar=false");
+    @Override
+    public void assertResult(String xml) {
+        assertThat(xml, stringContainsInOrder("-XFooBar=false", "version=\"12351\"", "max-age-seconds=\"12543\""));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectCreationTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectCreationTest.java
index cb5cb90..2c67ebd 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectCreationTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectCreationTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,25 +17,30 @@
 
 package com.sun.enterprise.configapi.tests;
 
+import com.sun.enterprise.config.serverbeans.AdminService;
 import com.sun.enterprise.config.serverbeans.DasConfig;
 import com.sun.enterprise.config.serverbeans.JavaConfig;
 import com.sun.enterprise.config.serverbeans.Profiler;
-import com.sun.enterprise.config.serverbeans.AdminService;
-
-import org.glassfish.hk2.api.ServiceLocator;
-import org.glassfish.tests.utils.Utils;
-import static org.junit.Assert.*;
-import org.junit.Test;
-import org.jvnet.hk2.config.AttributeChanges;
-import org.jvnet.hk2.config.ConfigBean;
-import org.jvnet.hk2.config.ConfigBeanProxy;
-import org.jvnet.hk2.config.ConfigSupport;
-import org.jvnet.hk2.config.TransactionFailure;
 
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
+
+import org.glassfish.hk2.api.ServiceLocator;
+import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.AttributeChanges;
+import org.jvnet.hk2.config.ConfigBean;
+import org.jvnet.hk2.config.ConfigBeanProxy;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.stringContainsInOrder;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 /**
  * User: Jerome Dochez
@@ -43,7 +49,7 @@
  */
 public class DirectCreationTest extends ConfigPersistence {
 
-    ServiceLocator habitat = Utils.instance.getHabitat(this);
+    private final ServiceLocator locator = Utils.instance.getHabitat(this);
 
     /**
      * Returns the file name without the .xml extension to load the test configuration
@@ -56,71 +62,65 @@
         return "DomainTest";
     }
 
+
     @Override
     public ServiceLocator getBaseServiceLocator() {
-        return habitat;
+        return locator;
     }
 
+
     @Override
     public ServiceLocator getHabitat() {
-            return getBaseServiceLocator();
+        return getBaseServiceLocator();
     }
 
-    public void doTest() throws TransactionFailure {
 
-        AdminService service = habitat.getService(AdminService.class);
-
-        ConfigBean serviceBean = (ConfigBean) ConfigBean.unwrap(service);
-        Class<?>[] subTypes = null;
-        try {
-            subTypes = ConfigSupport.getSubElementsTypes(serviceBean);
-        } catch (ClassNotFoundException e) {
-            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
-            throw new RuntimeException(e);
-        }
-
+    @Override
+    public void doTest() throws Exception {
+        AdminService service = locator.getService(AdminService.class);
+        ConfigBean serviceBean = (ConfigBean) Dom.unwrap(service);
+        Class<?>[] subTypes = ConfigSupport.getSubElementsTypes(serviceBean);
         ConfigSupport support = getBaseServiceLocator().getService(ConfigSupport.class);
-
-        assertNotNull("ConfigSupport not found", support);
+        assertNotNull(support, "ConfigSupport not found");
 
         for (Class<?> subType : subTypes) {
-
-            // TODO:  JL force compilation error to mark this probably edit point for grizzly config
             if (subType.getName().endsWith("DasConfig")) {
-                Map<String, String> configChanges = new HashMap<String, String>();
+                Map<String, String> configChanges = new HashMap<>();
                 configChanges.put("dynamic-reload-enabled", "true");
                 configChanges.put("autodeploy-dir", "funky-dir");
-                support.createAndSet(serviceBean, (Class<? extends ConfigBeanProxy>)subType, configChanges);
+                ConfigSupport.createAndSet(serviceBean, (Class<? extends ConfigBeanProxy>) subType, configChanges);
                 break;
             }
         }
 
-        support.createAndSet(serviceBean, DasConfig.class, (List) null);
+        support.createAndSet(serviceBean, DasConfig.class, (List<AttributeChanges>) null);
 
-        List<AttributeChanges> profilerChanges = new ArrayList<AttributeChanges>();
+        List<AttributeChanges> profilerChanges = new ArrayList<>();
         String[] values = { "-Xmx512m", "-RFtrq", "-Xmw24" };
         ConfigSupport.MultipleAttributeChanges multipleChanges = new ConfigSupport.MultipleAttributeChanges("jvm-options", values );
         String[] values1 = { "profile" };
         ConfigSupport.MultipleAttributeChanges multipleChanges1 = new ConfigSupport.MultipleAttributeChanges("name", values1 );
         profilerChanges.add(multipleChanges);
         profilerChanges.add(multipleChanges1);
-        support.createAndSet((ConfigBean) ConfigBean.unwrap(habitat.<JavaConfig>getService(JavaConfig.class))
-                , Profiler.class, profilerChanges);
+        support.createAndSet(unwrapConfigBean(), Profiler.class, profilerChanges);
     }
 
     @Test
-    public void directAttributeNameTest() throws ClassNotFoundException {
-
-        boolean foundOne=false;
-        for (String attrName :
-                ((ConfigBean) ConfigBean.unwrap(habitat.<JavaConfig>getService(JavaConfig.class))).model.getAttributeNames()) {
-            assertTrue(attrName!=null);
-            foundOne=true;
+    public void directAttributeNameTest() throws Exception {
+        Set<String> attributeNames = unwrapConfigBean().model.getAttributeNames();
+        assertThat(attributeNames, hasSize(13));
+        for (String attrName : attributeNames) {
+            assertNotNull(attrName);
         }
-        assertTrue(foundOne);
     }
 
-    public boolean assertResult(String s) {
-        return s.contains("autodeploy-dir=\"funky-dir\"");
+    @Override
+    public void assertResult(String xml) {
+        assertThat(xml, stringContainsInOrder("autodeploy-dir=\"funky-dir\""));
+    }
+
+
+    private ConfigBean unwrapConfigBean() {
+        return (ConfigBean) Dom.unwrap(locator.<JavaConfig> getService(JavaConfig.class));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectRemovalTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectRemovalTest.java
index 088c9f8..ea25f16 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectRemovalTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DirectRemovalTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -22,8 +23,13 @@
 import org.glassfish.tests.utils.Utils;
 import org.jvnet.hk2.config.ConfigBean;
 import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
 import org.jvnet.hk2.config.TransactionFailure;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.not;
+import static org.hamcrest.Matchers.stringContainsInOrder;
+
 /**
  * User: Jerome Dochez
  * Date: Mar 27, 2008
@@ -31,7 +37,7 @@
  */
 public class DirectRemovalTest extends ConfigPersistence {
 
-    ServiceLocator habitat = Utils.instance.getHabitat(this);
+    private final ServiceLocator habitat = Utils.instance.getHabitat(this);
 
     /**
      * Returns the file name without the .xml extension to load the test configuration
@@ -39,6 +45,7 @@
      *
      * @return the configuration file name
      */
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
@@ -48,22 +55,20 @@
         return habitat;
     }
 
+    @Override
     public void doTest() throws TransactionFailure {
-
         NetworkListeners listeners = habitat.getService(NetworkListeners.class);
-
-        ConfigBean serviceBean = (ConfigBean) ConfigBean.unwrap(listeners);
-
+        ConfigBean serviceBean = (ConfigBean) Dom.unwrap(listeners);
         for (NetworkListener listener : listeners.getNetworkListener()) {
             if (listener.getName().endsWith("http-listener-1")) {
-                ConfigSupport.deleteChild(serviceBean, (ConfigBean) ConfigBean.unwrap(listener));
+                ConfigSupport.deleteChild(serviceBean, (ConfigBean) Dom.unwrap(listener));
                 break;
             }
         }
     }
 
-    public boolean assertResult(String s) {
-        // we must not find it
-        return !s.contains("id=\"http-listener-1\"");
+    @Override
+    public void assertResult(String xml) {
+        assertThat(xml, not(stringContainsInOrder("id=\"http-listener-1\"")));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DomainTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DomainTest.java
index 0e2fa86..a96f7d4 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DomainTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DomainTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -17,8 +18,10 @@
 package com.sun.enterprise.configapi.tests;
 
 import com.sun.enterprise.config.serverbeans.Domain;
-import static org.junit.Assert.assertTrue;
-import org.junit.Test;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 /**
  * Domain related tests
@@ -29,9 +32,7 @@
 
     @Test
     public void domainExist() {
-
         Domain domain = getHabitat().getService(Domain.class);
-        assertTrue(domain != null);
+        assertNotNull(domain);
     }
-
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DuplicateKeyedElementTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DuplicateKeyedElementTest.java
index 964158d..f956623 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DuplicateKeyedElementTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/DuplicateKeyedElementTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,14 +17,13 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import java.beans.PropertyVetoException;
-
 import com.sun.enterprise.config.serverbeans.HttpService;
 import com.sun.enterprise.config.serverbeans.VirtualServer;
 import org.jvnet.hk2.config.types.Property;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import org.junit.Test;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
@@ -34,72 +34,55 @@
  * @author Jerome Dochez
  */
 public class DuplicateKeyedElementTest extends ConfigApiTest {
-    boolean result = false;
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Test(expected = TransactionFailure.class)
+    @Test
     public void duplicateKeyTest() throws TransactionFailure {
-        HttpService httpService = getHabitat().getService(HttpService.class);
-        assertNotNull(httpService);
-        // let's find a acceptable target.
-        VirtualServer target = null;
-        for (VirtualServer vs : httpService.getVirtualServer()) {
-            if (!vs.getProperty().isEmpty()) {
-                target = vs;
-                break;
-            }
-        }
+        final VirtualServer target = findVirtualServerWithProperties();
         assertNotNull(target);
         final Property prop = target.getProperty().get(0);
-        Property newProp = (Property) ConfigSupport.apply(new SingleConfigCode<VirtualServer>() {
-            public Object run(VirtualServer param) throws PropertyVetoException, TransactionFailure {
-                // first one is fine...
-                Property dupProp = param.createChild(Property.class);
-                dupProp.setName(prop.getName());
-                dupProp.setValue(prop.getValue().toUpperCase());
-                // this should fail...
-                param.getProperty().add(dupProp);
-                return dupProp;
-            }
-        }, target);
-        // if we arrive here, this is an error, we succeeded adding a property with
-        // the same key name.
-        assertTrue(false);
+        final SingleConfigCode<VirtualServer> configCode = virtualServer -> {
+            // first one is fine...
+            Property dupProp = virtualServer.createChild(Property.class);
+            dupProp.setName(prop.getName());
+            dupProp.setValue(prop.getValue().toUpperCase());
+            // this should fail...
+            throw assertThrows(IllegalArgumentException.class, () -> virtualServer.getProperty().add(dupProp));
+        };
+        assertThrows(TransactionFailure.class, () -> ConfigSupport.apply(configCode, target));
     }
 
-    @Test(expected = TransactionFailure.class)
+    @Test
     public void identicalKeyTest() throws TransactionFailure {
+        final VirtualServer target = findVirtualServerWithProperties();
+        assertNotNull(target);
+        final SingleConfigCode<VirtualServer> configCode = virtualServer -> {
+            // first one is fine...
+            Property firstProp = virtualServer.createChild(Property.class);
+            firstProp.setName("foo");
+            firstProp.setValue("bar");
+            virtualServer.getProperty().add(firstProp);
+            // this should fail...
+            Property secondProp = virtualServer.createChild(Property.class);
+            secondProp.setName("foo");
+            secondProp.setValue("bar");
+            throw assertThrows(IllegalArgumentException.class, () -> virtualServer.getProperty().add(secondProp));
+        };
+        assertThrows(TransactionFailure.class, () -> ConfigSupport.apply(configCode, target));
+    }
+
+    private VirtualServer findVirtualServerWithProperties() {
         HttpService httpService = getHabitat().getService(HttpService.class);
         assertNotNull(httpService);
-        // let's find a acceptable target.
-        VirtualServer target = null;
         for (VirtualServer vs : httpService.getVirtualServer()) {
             if (!vs.getProperty().isEmpty()) {
-                target = vs;
-                break;
+                return vs;
             }
         }
-        assertNotNull(target);
-        Property newProp = (Property) ConfigSupport.apply(new SingleConfigCode<VirtualServer>() {
-            public Object run(VirtualServer param) throws PropertyVetoException, TransactionFailure {
-                // first one is fine...
-                Property firstProp = param.createChild(Property.class);
-                firstProp.setName("foo");
-                firstProp.setValue("bar");
-                param.getProperty().add(firstProp);
-                // this should fail...
-                Property secondProp = param.createChild(Property.class);
-                secondProp.setName("foo");
-                secondProp.setValue("bar");
-                param.getProperty().add(secondProp);
-                return secondProp;
-            }
-        }, target);
-        // if we arrive here, this is an error, we succeeded adding a property with
-        // the same key name.
-        assertTrue(false);
+        return null;
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/EnabledTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/EnabledTest.java
index 1e9b5cc..f08eecf 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/EnabledTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/EnabledTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,14 +17,15 @@
 
 package com.sun.enterprise.configapi.tests;
 
+import java.util.List;
+
 import org.glassfish.grizzly.config.dom.NetworkConfig;
 import org.glassfish.grizzly.config.dom.NetworkListener;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
-import java.util.List;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * HttpListener.getEnabled() API test
@@ -31,13 +33,15 @@
  * User: Jerome Dochez Date: Feb 21, 2008 Time: 2:06:44 PM
  */
 public class EnabledTest extends ConfigApiTest {
+    private List<NetworkListener> listeners;
+
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    List<NetworkListener> listeners = null;
 
-    @Before
+    @BeforeEach
     public void setup() {
         NetworkConfig service = getHabitat().getService(NetworkConfig.class);
         assertTrue(service != null);
@@ -47,12 +51,11 @@
     @Test
     public void enabled() {
         for (NetworkListener listener : listeners) {
-            logger.fine("Listener " + listener.getName() + " enabled "
-                + listener.getEnabled());
+            logger.fine("Listener " + listener.getName() + " enabled " + listener.getEnabled());
             if ("http-listener-2".equals(listener.getName())) {
-                assertFalse(new Boolean(listener.getEnabled()));
+                assertFalse(Boolean.parseBoolean(listener.getEnabled()));
             } else {
-                assertTrue(new Boolean(listener.getEnabled()));
+                assertTrue(Boolean.parseBoolean(listener.getEnabled()));
             }
         }
     }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/GetElementTypeByNameTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/GetElementTypeByNameTest.java
index 5458a7d..dc1b5ae 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/GetElementTypeByNameTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/GetElementTypeByNameTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,12 +17,15 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.junit.Test;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import com.sun.enterprise.config.serverbeans.Config;
+
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigBeanProxy;
 import org.jvnet.hk2.config.ConfigSupport;
-import com.sun.enterprise.config.serverbeans.Config;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.core.StringEndsWith.endsWith;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 /**
  * Test the getElementTypeByName ConfigSupport API
@@ -30,21 +34,17 @@
  */
 public class GetElementTypeByNameTest extends ConfigApiTest {
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
 
     @Test
-    public void testAppRoot() {
-        Config c = getHabitat().getService(Config.class);
-        Class<? extends ConfigBeanProxy> elementType = null;
-        try {
-            elementType = ConfigSupport.getElementTypeByName(c, "admin-service");
-        } catch (Exception e) {
-            e.printStackTrace();
-        }
+    public void testAppRoot() throws Exception {
+        Config cfg = getHabitat().getService(Config.class);
+        Class<? extends ConfigBeanProxy> elementType = ConfigSupport.getElementTypeByName(cfg, "admin-service");
         assertNotNull(elementType);
-        assertTrue(elementType.getName().endsWith("AdminService"));
+        assertThat(elementType.getName(), endsWith("AdminService"));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpListenerTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpListenerTest.java
index 32991e3..b486e36 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpListenerTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpListenerTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -19,13 +20,15 @@
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.grizzly.config.dom.NetworkListeners;
 import org.glassfish.grizzly.config.dom.Transport;
-import static org.junit.Assert.assertTrue;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
 /**
  * HttpListener related tests
  *
@@ -33,46 +36,41 @@
  */
 public class HttpListenerTest extends ConfigApiTest {
 
+    private NetworkListener listener;
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    NetworkListener listener = null;
 
-    @Before
+    @BeforeEach
     public void setup() {
         NetworkListeners service = getHabitat().getService(NetworkListeners.class);
-        assertTrue(service!=null);
+        assertNotNull(service);
         for (NetworkListener item : service.getNetworkListener()) {
             if ("http-listener-1".equals(item.getName())) {
                 listener= item;
                 break;
             }
         }
-
-        logger.fine("listener = " + listener);
-        assertTrue(listener!=null);
-
+        assertNotNull(listener);
     }
 
     @Test
     public void portTest() {
-        logger.fine("port = " + listener.getPort());
-        assertTrue("8080".equals(listener.getPort()));
+        assertEquals("8080", listener.getPort());
     }
 
     @Test
     public void validTransaction() throws TransactionFailure {
-
-        ConfigSupport.apply(new SingleConfigCode<Transport>() {
-            public Object run(Transport okToChange) {
-                okToChange.setAcceptorThreads("2");
-                logger.fine("ID inside the transaction is " + okToChange.getName());
-                return null;
-            }
-        }, listener.findTransport());
+        SingleConfigCode<Transport> configCode = transport -> {
+            transport.setAcceptorThreads("2");
+            logger.fine("ID inside the transaction is " + transport.getName());
+            return null;
+        };
+        ConfigSupport.apply(configCode, listener.findTransport());
         logger.fine("ID outside the transaction is " + listener.getName());
-        assertTrue("2".equals(listener.findTransport().getAcceptorThreads()));
+        assertEquals("2", listener.findTransport().getAcceptorThreads());
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpServiceTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpServiceTest.java
index c698314..123a95a 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpServiceTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpServiceTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -21,76 +22,72 @@
 import org.glassfish.grizzly.config.dom.NetworkConfig;
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.grizzly.config.dom.Protocol;
-import static junit.framework.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 /**
  * HttpService related tests
  *
  * @author Jerome Dochez
  */
 public class HttpServiceTest extends ConfigApiTest {
+
+    private NetworkListener listener;
+
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    NetworkListener listener = null;
 
-    @Before
+    @BeforeEach
     public void setup() {
         listener = getHabitat().<NetworkConfig>getService(NetworkConfig.class).getNetworkListener("admin-listener");
-        assertTrue(listener != null);
+        assertNotNull(listener);
     }
 
     @Test
     public void connectionTest() {
         final String max = listener.findHttpProtocol().getHttp().getMaxConnections();
-        logger.fine("Max connections = " + max);
-        assertEquals("Should only allow 250 connections.  The default is 256, however.", "250", max);
+        assertEquals("250", max, "Should only allow 250 connections. The default is 256, however.");
     }
 
     @Test
     public void validTransaction() throws TransactionFailure {
         final String max = listener.findHttpProtocol().getHttp().getMaxConnections();
 
-        ConfigSupport.apply(new SingleConfigCode<NetworkListener>() {
-            public Object run(NetworkListener okToChange) throws TransactionFailure {
-                final Http http = okToChange.createChild(Http.class);
-                http.setMaxConnections("100");
-                http.setTimeoutSeconds("65");
-                http.setFileCache(http.createChild(FileCache.class));
-                ConfigSupport.apply(new SingleConfigCode<Protocol>() {
-                    @Override
-                    public Object run(Protocol param) {
-                        param.setHttp(http);
-                        return null;
-                    }
-                }, okToChange.findHttpProtocol());
-                return http;
-            }
-        }, listener);
-
-        ConfigSupport.apply(new SingleConfigCode<Http>() {
-            @Override
-            public Object run(Http param) {
-                param.setMaxConnections(max);
+        SingleConfigCode<NetworkListener> listenerConfigCode = networkListener -> {
+            final Http http = networkListener.createChild(Http.class);
+            http.setMaxConnections("100");
+            http.setTimeoutSeconds("65");
+            http.setFileCache(http.createChild(FileCache.class));
+            SingleConfigCode<Protocol> protocolConfigCode = protocol -> {
+                protocol.setHttp(http);
                 return null;
-            }
-        }, listener.findHttpProtocol().getHttp());
-        try {
-            ConfigSupport.apply(new SingleConfigCode<Http>() {
-                public Object run(Http param) throws TransactionFailure {
-                    param.setMaxConnections("7");
-                    throw new TransactionFailure("Sorry, changed my mind", null);
-                }
-            }, listener.findHttpProtocol().getHttp());
-        } catch (TransactionFailure e) {
-            logger.fine("good, got my exception about changing my mind");
-        }
+            };
+            ConfigSupport.apply(protocolConfigCode, networkListener.findHttpProtocol());
+            return http;
+        };
+        ConfigSupport.apply(listenerConfigCode, listener);
+
+        SingleConfigCode<Http> httpConfigCode = (SingleConfigCode<Http>) http -> {
+            http.setMaxConnections(max);
+            return null;
+        };
+        ConfigSupport.apply(httpConfigCode, listener.findHttpProtocol().getHttp());
+        SingleConfigCode<Http> configCode = http -> {
+            http.setMaxConnections("7");
+            throw new TransactionFailure("Sorry, changed my mind", null);
+        };
+        assertThrows(TransactionFailure.class,
+            () -> ConfigSupport.apply(configCode, listener.findHttpProtocol().getHttp()));
+        assertEquals(max, listener.findHttpProtocol().getHttp().getMaxConnections());
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/JavaConfigSubTypesTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/JavaConfigSubTypesTest.java
index 2b0653d..cb47b86 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/JavaConfigSubTypesTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/JavaConfigSubTypesTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,20 +17,23 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.junit.Test;
-import org.junit.Assert;
-import org.jvnet.hk2.config.ConfigSupport;
-import org.jvnet.hk2.config.ConfigBean;
-import org.jvnet.hk2.config.TransactionFailure;
-import org.jvnet.hk2.config.SingleConfigCode;
-import org.glassfish.hk2.api.ServiceLocator;
-import org.glassfish.tests.utils.Utils;
 import com.sun.enterprise.config.serverbeans.JavaConfig;
 
-import java.util.logging.Logger;
-import java.util.logging.Level;
 import java.util.List;
-import java.beans.PropertyVetoException;
+import java.util.logging.Logger;
+
+import org.glassfish.hk2.api.ServiceLocator;
+import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigBean;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
+import org.jvnet.hk2.config.SingleConfigCode;
+import org.jvnet.hk2.config.TransactionFailure;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.stringContainsInOrder;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * User: Jerome Dochez
@@ -38,26 +42,7 @@
  */
 public class JavaConfigSubTypesTest extends ConfigPersistence {
 
-
-    @Test
-    public void testSubTypesOfDomain() {
-        JavaConfig config = super.getHabitat().getService(JavaConfig.class);
-        try {
-            Class<?>[] subTypes = ConfigSupport.getSubElementsTypes((ConfigBean) ConfigBean.unwrap(config));
-            boolean found=false;
-            for (Class subType : subTypes) {
-                Logger.getAnonymousLogger().fine("Found class " + subType);
-                if (subType.getName().equals(List.class.getName())) {
-                    found=true;
-                }
-            }
-            Assert.assertTrue(found);;
-        } catch(ClassNotFoundException e) {
-            logger.log(Level.SEVERE, e.getMessage(), e);
-        }
-    }
-
-    ServiceLocator habitat = Utils.instance.getHabitat(this);
+    private final ServiceLocator habitat = Utils.instance.getHabitat(this);
 
     /**
      * Returns the file name without the .xml extension to load the test configuration
@@ -65,38 +50,54 @@
      *
      * @return the configuration file name
      */
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
+
     @Override
     public ServiceLocator getBaseServiceLocator() {
         return habitat;
     }
 
+
     @Override
     public ServiceLocator getHabitat() {
-            return getBaseServiceLocator();
+        return getBaseServiceLocator();
     }
 
+
+    @Override
     @Test
     public void doTest() throws TransactionFailure {
-
-
         JavaConfig javaConfig = habitat.getService(JavaConfig.class);
+        SingleConfigCode<JavaConfig> configCode = (SingleConfigCode<JavaConfig>) jvm -> {
+            List<String> jvmOptions = jvm.getJvmOptions();
+            jvmOptions.add("-XFooBar=true");
+            return jvmOptions;
+        };
+        ConfigSupport.apply(configCode, javaConfig);
+    }
 
-        ConfigSupport.apply(new SingleConfigCode<JavaConfig>() {
-            public Object run(JavaConfig param) throws PropertyVetoException, TransactionFailure {
-                List<String> jvmOptions = param.getJvmOptions();
-                jvmOptions.add("-XFooBar=true");
-                return jvmOptions;
+
+    @Override
+    public void assertResult(String xml) {
+        assertThat(xml, stringContainsInOrder("-XFooBar"));
+    }
+
+
+    @Test
+    public void testSubTypesOfDomain() throws Exception {
+        JavaConfig config = super.getHabitat().getService(JavaConfig.class);
+        Class<?>[] subTypes = ConfigSupport.getSubElementsTypes((ConfigBean) Dom.unwrap(config));
+        boolean found = false;
+        for (Class<?> subType : subTypes) {
+            Logger.getAnonymousLogger().fine("Found class " + subType);
+            if (subType.getName().equals(List.class.getName())) {
+                found = true;
             }
-        }, javaConfig);
-
+        }
+        assertTrue(found);
     }
-
-    public boolean assertResult(String s) {
-        return s.indexOf("-XFooBar")!=-1;
-    }
-
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ModulesTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ModulesTest.java
index aeaa54a..cf80195 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ModulesTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ModulesTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -17,39 +18,41 @@
 package com.sun.enterprise.configapi.tests;
 
 import com.sun.enterprise.config.serverbeans.Applications;
-import org.glassfish.api.admin.config.ApplicationName;
-import static org.junit.Assert.assertTrue;
-import org.junit.Before;
-import org.junit.Test;
 
 import java.util.Collection;
 
+import org.glassfish.api.admin.config.ApplicationName;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
 /**
  * Modules related tests
  */
 public class ModulesTest extends ConfigApiTest {
 
+    private Collection<? extends ApplicationName> modules;
+
     @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    Collection<? extends ApplicationName> modules = null;
 
-    @Before
+    @BeforeEach
     public void setup() {
         Applications apps = getHabitat().getService(Applications.class);
-        assertTrue(apps!=null);
+        assertNotNull(apps);
         modules = apps.getModules();
-        assertTrue(modules!=null);
-
+        assertNotNull(modules);
     }
 
     @Test
     public void modulesTest() {
         for (ApplicationName module : modules) {
             logger.fine("Found module " + module.getName());
-            assertTrue(module.getName()!=null);
+            assertNotNull(module.getName());
         }
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentConfigListenerTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentConfigListenerTest.java
index ab41839..2adb968 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentConfigListenerTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentConfigListenerTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,23 +17,23 @@
 
 package com.sun.enterprise.configapi.tests;
 
+import java.util.List;
+
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.grizzly.config.dom.NetworkListeners;
 import org.glassfish.hk2.api.ServiceHandle;
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
-import static org.junit.Assert.assertTrue;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.Assert;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.ObservableBean;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 import org.jvnet.hk2.config.Transactions;
 
-import java.util.Collection;
-import java.util.List;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * This test will ensure that when a class is injected with a parent bean and a child
@@ -43,54 +44,48 @@
  */
 public class ParentConfigListenerTest extends ConfigApiTest {
 
-    ServiceLocator habitat;
+    private ServiceLocator locator;
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
-        habitat = Utils.instance.getHabitat(this);
+        locator = Utils.instance.getHabitat(this);
     }
 
-
-
-
     @Test
     public void addHttpListenerTest() throws TransactionFailure {
-        NetworkListenersContainer container = habitat.getService(NetworkListenersContainer.class);
-
-        ConfigSupport.apply(new SingleConfigCode<NetworkListeners>() {
-
-            public Object run(NetworkListeners param) throws TransactionFailure {
-                NetworkListener newListener = param.createChild(NetworkListener.class);
-                newListener.setName("Funky-Listener");
-                newListener.setPort("8078");
-                param.getNetworkListener().add(newListener);
-                return null;
-            }
-        }, container.httpService);
+        NetworkListenersContainer container = locator.getService(NetworkListenersContainer.class);
+        SingleConfigCode<NetworkListeners> configCode = listeners -> {
+            NetworkListener newListener = listeners.createChild(NetworkListener.class);
+            newListener.setName("Funky-Listener");
+            newListener.setPort("8078");
+            listeners.getNetworkListener().add(newListener);
+            return null;
+        };
+        ConfigSupport.apply(configCode, container.httpService);
 
         getHabitat().<Transactions>getService(Transactions.class).waitForDrain();
         assertTrue(container.received);
         ObservableBean bean = (ObservableBean) ConfigSupport.getImpl(container.httpService);
 
         // let's check that my newly added listener is available in the habitat.
-        List<ServiceHandle<NetworkListener>> networkListeners = habitat.getAllServiceHandles(NetworkListener.class);
+        List<ServiceHandle<NetworkListener>> networkListeners = locator.getAllServiceHandles(NetworkListener.class);
         boolean found = false;
-
         for (ServiceHandle<NetworkListener> nlSH : networkListeners) {
-            NetworkListener nl = (NetworkListener) nlSH.getService();
+            NetworkListener nl = nlSH.getService();
             if (nl.getName().equals("Funky-Listener")) {
-                found=true;
+                found = true;
             }
         }
-        Assert.assertTrue("Newly added listener not found", found);
+        assertTrue(found, "Newly added listener not found");
 
         // direct access.
-        NetworkListener nl = habitat.getService(NetworkListener.class, "Funky-Listener");
-        Assert.assertTrue("Direct access to newly added listener failed", nl!=null);
+        NetworkListener networkListener = locator.getService(NetworkListener.class, "Funky-Listener");
+        assertNotNull(networkListener, "Direct access to newly added listener failed");
         bean.removeListener(container);
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentTest.java
index cfac43c..4ff1b79 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/ParentTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -18,10 +19,11 @@
 
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.grizzly.config.dom.NetworkListeners;
-import static org.junit.Assert.assertNotNull;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigBeanProxy;
 
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
 /**
  * test the getParentAPI.
  *
@@ -29,7 +31,7 @@
  */
 public class ParentTest extends ConfigApiTest {
 
-
+    @Override
     public String getFileName() {
         return "DomainTest";
     }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PersistenceTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PersistenceTest.java
index 948b4a6..8b5ebb7 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PersistenceTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PersistenceTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -22,29 +23,33 @@
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.stringContainsInOrder;
+
 /**
  * Test the persistence to a file...
  */
 public class PersistenceTest extends ConfigPersistence {
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
+
+    @Override
     public void doTest() throws TransactionFailure {
         NetworkListeners service = getHabitat().getService(NetworkListeners.class);
-        // now do a transaction
-
-        ConfigSupport.apply(new SingleConfigCode<Transport>() {
-            public Object run(Transport param) {
-                param.setAcceptorThreads("8989");
-                return null;
-            }
-        }, service.getNetworkListener().get(0).findTransport());
-        //To change body of implemented methods use File | Settings | File Templates.
+        SingleConfigCode<Transport> configCode = (SingleConfigCode<Transport>) transport -> {
+            transport.setAcceptorThreads("8989");
+            return null;
+        };
+        ConfigSupport.apply(configCode, service.getNetworkListener().get(0).findTransport());
     }
 
-    public boolean assertResult(String s) {
-        return s.contains("acceptor-threads=\"8989\"");
+
+    @Override
+    public void assertResult(String xml) {
+        assertThat(xml, stringContainsInOrder("acceptor-threads=\"8989\""));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PropertyChangeListenerTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PropertyChangeListenerTest.java
index fba2e04..a7d07fd 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PropertyChangeListenerTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/PropertyChangeListenerTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,19 +17,26 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.jvnet.hk2.config.*;
-import org.jvnet.hk2.config.types.Property;
-import org.junit.Before;
-import org.junit.Test;
-import static org.junit.Assert.*;
+import com.sun.enterprise.config.serverbeans.HttpService;
+import com.sun.enterprise.config.serverbeans.VirtualServer;
+
+import java.beans.PropertyChangeEvent;
 
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
-import com.sun.enterprise.config.serverbeans.*;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigListener;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.ObservableBean;
+import org.jvnet.hk2.config.SingleConfigCode;
+import org.jvnet.hk2.config.TransactionFailure;
+import org.jvnet.hk2.config.Transactions;
+import org.jvnet.hk2.config.UnprocessedChangeEvents;
+import org.jvnet.hk2.config.types.Property;
 
-
-import java.beans.PropertyVetoException;
-import java.beans.PropertyChangeEvent;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * This test listen to a property change event only injecting the parent containing the property.
@@ -37,54 +45,55 @@
  */
 public class PropertyChangeListenerTest  extends ConfigApiTest implements ConfigListener {
 
-    ServiceLocator habitat;
-    boolean result = false;
+    private ServiceLocator locator;
+    private boolean result;
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
-        habitat = Utils.instance.getHabitat(this);
+        locator = Utils.instance.getHabitat(this);
     }
 
     @Test
     public void propertyChangeEventReceptionTest() throws TransactionFailure {
 
-        HttpService  httpService = habitat.getService(HttpService.class);
+        HttpService  httpService = locator.getService(HttpService.class);
         assertNotNull(httpService);
 
        // let's find a acceptable target.
-        VirtualServer target =null;
-        for (VirtualServer vs : httpService.getVirtualServer()) {
-            if (!vs.getProperty().isEmpty()) {
-                target = vs;
-                break;
-            }
-        }
+       VirtualServer target = null;
+       for (VirtualServer vs : httpService.getVirtualServer()) {
+           if (!vs.getProperty().isEmpty()) {
+               target = vs;
+               break;
+           }
+       }
 
-        assertNotNull(target);
+       assertNotNull(target);
 
-        ((ObservableBean) ConfigSupport.getImpl(target)).addListener(this);
-        final Property prop  = target.getProperty().get(0);
+       ((ObservableBean) ConfigSupport.getImpl(target)).addListener(this);
+       final Property prop = target.getProperty().get(0);
 
-        ConfigSupport.apply(new SingleConfigCode<Property>() {
+       SingleConfigCode<Property> configCode = property -> {
+           // first one is fine...
+           property.setValue(prop.getValue().toUpperCase());
+           return null;
+       };
+       ConfigSupport.apply(configCode, prop);
 
-            public Object run(Property param) throws PropertyVetoException, TransactionFailure {
-                // first one is fine...
-                param.setValue(prop.getValue().toUpperCase());
-                return null;
-            }
-        }, prop);
+       getHabitat().<Transactions> getService(Transactions.class).waitForDrain();
+       assertTrue(result);
+       ((ObservableBean) ConfigSupport.getImpl(target)).removeListener(this);
+   }
 
-        getHabitat().<Transactions>getService(Transactions.class).waitForDrain();
-        assertTrue(result);
-        ((ObservableBean) ConfigSupport.getImpl(target)).removeListener(this);
-    }
 
-    public UnprocessedChangeEvents changed(PropertyChangeEvent[] events) {
-        result = true;
-        return null;
-    }
+   @Override
+   public UnprocessedChangeEvents changed(PropertyChangeEvent[] events) {
+       result = true;
+       return null;
+   }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/RawValueTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/RawValueTest.java
index a69565d..5935734 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/RawValueTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/RawValueTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,38 +17,43 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.junit.Before;
-import org.junit.Test;
-import static org.junit.Assert.*;
-import org.glassfish.config.support.GlassFishConfigBean;
 import com.sun.enterprise.config.serverbeans.Domain;
 
+import org.glassfish.config.support.GlassFishConfigBean;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.CoreMatchers.startsWith;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+
 /**
- * Created by IntelliJ IDEA.
  * User: dochez
  * Date: Jan 30, 2008
  * Time: 11:18:52 AM
- * To change this template use File | Settings | File Templates.
  */
 public class RawValueTest extends ConfigApiTest {
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
         System.setProperty("com.sun.aas.instanceRoot", "cafebabe");
     }
 
-
     @Test
     public void testAppRoot() {
         Domain domain = getHabitat().getService(Domain.class);
         Domain rawDomain = GlassFishConfigBean.getRawView(domain);
         String appRoot = domain.getApplicationRoot();
         String appRawRoot = rawDomain.getApplicationRoot();
-        assertFalse(appRawRoot.equals(appRoot));
-        assertTrue(appRawRoot.startsWith("${"));
+        assertAll(
+            () -> assertNotEquals(appRoot, appRawRoot),
+            () -> assertThat(appRawRoot, startsWith("${"))
+        );
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/Ssl2EnabledTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/Ssl2EnabledTest.java
index 8a2cc7e..bd92a42 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/Ssl2EnabledTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/Ssl2EnabledTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,31 +17,33 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertTrue;
-
 import org.glassfish.grizzly.config.dom.NetworkConfig;
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.grizzly.config.dom.Protocol;
 import org.glassfish.grizzly.config.dom.Ssl;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * User: Jerome Dochez Date: Mar 4, 2008 Time: 2:44:59 PM
  */
 public class Ssl2EnabledTest extends ConfigApiTest {
+
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    NetworkConfig config = null;
+    private NetworkConfig config;
 
-    @Before
+    @BeforeEach
     public void setup() {
         config = getHabitat().getService(NetworkConfig.class);
-        assertTrue(config != null);
-
+        assertNotNull(config);
     }
 
     @Test
@@ -50,13 +53,9 @@
             if (httpProtocol != null) {
                 Ssl ssl = httpProtocol.getSsl();
                 if (ssl != null) {
-                    try {
-                        logger.fine("SSL2 ENABLED = " + ssl.getSsl2Enabled());
-                        assertFalse(Boolean.parseBoolean(ssl.getSsl2Enabled()));
-                        assertFalse(Boolean.parseBoolean(ssl.getSsl3Enabled()));
-                    } catch (Exception e) {
-                        e.printStackTrace();
-                    }
+                    assertFalse(Boolean.parseBoolean(ssl.getSsl2Enabled()));
+                    assertFalse(Boolean.parseBoolean(ssl.getSsl3Enabled()));
+                    assertTrue(Boolean.parseBoolean(ssl.getTlsEnabled()));
                 }
             }
         }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/SubTypesTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/SubTypesTest.java
index 8c62e50..93a1788 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/SubTypesTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/SubTypesTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -18,11 +19,17 @@
 
 import com.sun.enterprise.config.serverbeans.Domain;
 
-import java.util.logging.Logger;
-import org.junit.Test;
-import static org.junit.Assert.assertTrue;
-import org.jvnet.hk2.config.ConfigSupport;
+import java.util.Set;
+
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigBean;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.equalTo;
+import static org.hamcrest.Matchers.hasItems;
+import static org.junit.jupiter.api.Assertions.assertAll;
 
 
 /**
@@ -33,43 +40,25 @@
 public class SubTypesTest extends ConfigApiTest {
 
     // not testing all the sub types, just a few to be sure it works ok.
-    String expectedClassNames[] = {
-        "com.sun.enterprise.config.serverbeans.Applications",
-        "com.sun.enterprise.config.serverbeans.Configs",
-        "com.sun.enterprise.config.serverbeans.Clusters"
+    private static final Class<?>[] expectedClassNames = {
+        com.sun.enterprise.config.serverbeans.Applications.class,
+        com.sun.enterprise.config.serverbeans.Configs.class,
+        com.sun.enterprise.config.serverbeans.Clusters.class
     };
 
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
     @Test
-    public void testSubTypesOfDomain() {
+    public void testSubTypesOfDomain() throws Exception {
         Domain domain = super.getHabitat().getService(Domain.class);
-        try {
-            Class<?>[] subTypes = ConfigSupport.getSubElementsTypes((ConfigBean) ConfigBean.unwrap(domain));
-            for (Class subType : subTypes) {
-                Logger.getAnonymousLogger().fine("Found class" + subType);
-            }
-            for (String expectedClassName : expectedClassNames) {
-                boolean found=false;
-                for (Class<?> subType : subTypes)  {
-                    if (subType.getName().equals(expectedClassName)) {
-                        found = true;
-                        break;
-                    }
-                }
-                if (!found) {
-                    Logger.getAnonymousLogger().severe("Cannot find " + expectedClassName + " from list of subtypes");
-                    for (Class subType : subTypes) {
-                        Logger.getAnonymousLogger().severe("Found class" + subType);
-                    }
-                    throw new RuntimeException("Cannot find " + expectedClassName);
-                }
-            }
-        } catch(ClassNotFoundException e) {
-            e.printStackTrace();
-        }
+        Class<?>[] subTypes = ConfigSupport.getSubElementsTypes((ConfigBean) Dom.unwrap(domain));
+        assertAll(
+            () -> assertThat(subTypes.length, equalTo(12)),
+            () -> assertThat(Set.of(subTypes), hasItems(expectedClassNames))
+        );
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionCallBackTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionCallBackTest.java
index 688d6e5..c9b8e9d 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionCallBackTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionCallBackTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,20 +17,24 @@
 
 package com.sun.enterprise.configapi.tests;
 
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.HashMap;
+import java.util.Map;
+
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.grizzly.config.dom.NetworkListeners;
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
 import org.jvnet.hk2.config.ConfigBean;
 import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
 import org.jvnet.hk2.config.TransactionCallBack;
 import org.jvnet.hk2.config.TransactionFailure;
 import org.jvnet.hk2.config.WriteableView;
 
-import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.util.HashMap;
-import java.util.Map;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.stringContainsInOrder;
 
 /**
  * User: Jerome Dochez
@@ -38,7 +43,7 @@
  */
 public class TransactionCallBackTest extends ConfigPersistence {
 
-    ServiceLocator habitat = Utils.instance.getHabitat(this);
+    private final ServiceLocator locator = Utils.instance.getHabitat(this);
 
     /**
      * Returns the file name without the .xml extension to load the test configuration
@@ -46,49 +51,51 @@
      *
      * @return the configuration file name
      */
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
+
     @Override
     public ServiceLocator getBaseServiceLocator() {
-        return habitat;
+        return locator;
     }
 
+
     @Override
     public ServiceLocator getHabitat() {
-            return getBaseServiceLocator();
+        return getBaseServiceLocator();
     }
 
+
+    @Override
     public void doTest() throws TransactionFailure {
-        ConfigBean serviceBean = (ConfigBean) ConfigBean.unwrap(habitat.<NetworkListeners>getService(NetworkListeners.class));
-        Map<String, String> configChanges = new HashMap<String, String>();
+        ConfigBean serviceBean = (ConfigBean) Dom.unwrap(locator.<NetworkListeners> getService(NetworkListeners.class));
+        Map<String, String> configChanges = new HashMap<>();
         configChanges.put("name", "funky-listener");
 
-        ConfigSupport.createAndSet(serviceBean, NetworkListener.class, configChanges,
-                new TransactionCallBack<WriteableView>() {
-                    @SuppressWarnings({"unchecked"})
-                    public void performOn(WriteableView param) throws TransactionFailure {
-                        // if you know the type...
-                        NetworkListener listener = param.getProxy(NetworkListener.class);
-                        listener.setName("Aleksey");
-                        // if you don't know the type
-                        Method m;
-                        try {
-                            m = param.getProxyType().getMethod("setAddress", String.class);
-                            m.invoke(param.getProxy(param.getProxyType()), "localhost");
-                        } catch (NoSuchMethodException e) {
-                            throw new TransactionFailure("Cannot find getProperty method", e);
-                        } catch (IllegalAccessException e) {
-                            throw new TransactionFailure("Cannot call getProperty method", e);
-                        } catch (InvocationTargetException e) {
-                            throw new TransactionFailure("Cannot call getProperty method", e);
-                        }
-                    }
-                });
+        TransactionCallBack<WriteableView> callBack = view -> {
+            // if you know the type...
+            NetworkListener listener = view.getProxy(NetworkListener.class);
+            listener.setName("Aleksey");
+            // if you don't know the type
+            Method setAddressMethod;
+            try {
+                setAddressMethod = view.getProxyType().getMethod("setAddress", String.class);
+                setAddressMethod.invoke(view.getProxy(view.getProxyType()), "localhost");
+            } catch (NoSuchMethodException e1) {
+                throw new TransactionFailure("Cannot find getProperty method", e1);
+            } catch (IllegalAccessException | InvocationTargetException e2) {
+                throw new TransactionFailure("Cannot call getProperty method", e2);
+            }
+        };
+        ConfigSupport.createAndSet(serviceBean, NetworkListener.class, configChanges, callBack);
     }
 
-    public boolean assertResult(String s) {
-        return s.contains("Aleksey") && s.contains("localhost");
+
+    @Override
+    public void assertResult(String xml) {
+        assertThat(xml, stringContainsInOrder("localhost", "Aleksey"));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionListenerTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionListenerTest.java
index ea9b989..8e0c53a 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionListenerTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TransactionListenerTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -17,11 +18,14 @@
 package com.sun.enterprise.configapi.tests;
 
 import com.sun.enterprise.config.serverbeans.HttpService;
+
+import java.beans.PropertyChangeEvent;
+import java.util.List;
+
 import org.glassfish.grizzly.config.dom.Http;
 import org.glassfish.grizzly.config.dom.NetworkConfig;
 import org.glassfish.grizzly.config.dom.NetworkListener;
-import static org.junit.Assert.assertTrue;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
@@ -29,35 +33,44 @@
 import org.jvnet.hk2.config.Transactions;
 import org.jvnet.hk2.config.UnprocessedChangeEvents;
 
-import java.beans.PropertyChangeEvent;
-import java.util.List;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
- * Created by IntelliJ IDEA.
  * User: dochez
  * Date: Jan 23, 2008
  * Time: 10:48:55 PM
  */
 public class TransactionListenerTest extends ConfigApiTest {
+
+    private HttpService httpService;
+    private List<PropertyChangeEvent> events;
+
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    HttpService httpService = null;
-    List<PropertyChangeEvent> events = null;
 
     @Test
     public void transactionEvents() throws Exception, TransactionFailure {
         httpService = getHabitat().getService(HttpService.class);
-        NetworkConfig networkConfig = getHabitat().getService(NetworkConfig.class);
-        final NetworkListener netListener = networkConfig.getNetworkListeners()
-            .getNetworkListener().get(0);
+        final NetworkConfig networkConfig = getHabitat().getService(NetworkConfig.class);
+        final NetworkListener netListener = networkConfig.getNetworkListeners().getNetworkListener().get(0);
         final Http http = netListener.findHttpProtocol().getHttp();
         final TransactionListener listener = new TransactionListener() {
-                public void transactionCommited(List<PropertyChangeEvent> changes) {
-                    events = changes;
-                }
 
+            @Override
+            public void transactionCommited(List<PropertyChangeEvent> changes) {
+                events = changes;
+            }
+
+
+            @Override
             public void unprocessedTransactedEvents(List<UnprocessedChangeEvents> changes) {
             }
         };
@@ -66,41 +79,34 @@
 
         try {
             transactions.addTransactionsListener(listener);
-            assertTrue(httpService!=null);
+            assertNotNull(httpService);
             logger.fine("Max connections = " + http.getMaxConnections());
-            ConfigSupport.apply(new SingleConfigCode<Http>() {
-
-                public Object run(Http param) {
-                    param.setMaxConnections("500");
-                    return null;
-                }
-            }, http);
+            SingleConfigCode<Http> configCode = httpConfig -> {
+                httpConfig.setMaxConnections("500");
+                return null;
+            };
+            ConfigSupport.apply(configCode, http);
             assertTrue("500".equals(http.getMaxConnections()));
 
             transactions.waitForDrain();
 
-            assertTrue(events!=null);
-            logger.fine("Number of events " + events.size());
-            assertTrue(events.size()==1);
+            assertNotNull(events);
+            assertThat(events, hasSize(1));
             PropertyChangeEvent event = events.iterator().next();
-            assertTrue("max-connections".equals(event.getPropertyName()));
-            assertTrue("500".equals(event.getNewValue().toString()));
-            assertTrue("250".equals(event.getOldValue().toString()));
-        } catch(Exception t) {
-            t.printStackTrace();
-            throw t;
-        }finally {
+            assertAll(
+                () -> assertEquals("max-connections", event.getPropertyName()),
+                () -> assertEquals("500", event.getNewValue().toString()),
+                () -> assertEquals("250", event.getOldValue().toString())
+            );
+        } finally {
             transactions.removeTransactionsListener(listener);
         }
 
         // put back the right values in the domain to avoid test collisions
-        ConfigSupport.apply(new SingleConfigCode<Http>() {
-
-            public Object run(Http param) {
-                param.setMaxConnections("250");
-                return null;
-            }
-        }, http);
-
+        SingleConfigCode<Http> configCode = httpConfig -> {
+            httpConfig.setMaxConnections("250");
+            return null;
+        };
+        ConfigSupport.apply(configCode, http);
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedValuesTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedValuesTest.java
index ddc0e3a..b1ccfb6 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedValuesTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedValuesTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,14 +17,18 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.junit.Test;
-import org.junit.Before;
-import static org.junit.Assert.*;
 import com.sun.enterprise.config.serverbeans.Domain;
 import com.sun.enterprise.config.serverbeans.JavaConfig;
 
 import java.io.File;
 
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.stringContainsInOrder;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 /**
  * Simple test for translated values access
  *
@@ -31,11 +36,12 @@
  */
 public class TranslatedValuesTest extends ConfigApiTest {
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
         System.setProperty("com.sun.aas.instanceRoot", "cafebabe");
         System.setProperty("com.sun.aas.javaRoot", System.getProperty("user.home"));
@@ -54,9 +60,8 @@
         if (System.getProperty("user.home").contains(File.separator)) {
             JavaConfig config = getHabitat().getService(JavaConfig.class);
             String javaRoot = config.getJavaHome();
-            assertTrue(javaRoot.indexOf(File.separatorChar)!=-1);
+            assertThat(javaRoot, stringContainsInOrder(File.separator));
         }
-        assertTrue(true);
     }
 
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedViewCreationTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedViewCreationTest.java
index 625289b..5427eea 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedViewCreationTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TranslatedViewCreationTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,19 +17,18 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import java.beans.PropertyChangeEvent;
-import java.beans.PropertyVetoException;
-import java.util.List;
-
 import com.sun.enterprise.config.serverbeans.HttpService;
 import com.sun.enterprise.config.serverbeans.VirtualServer;
+
+import java.beans.PropertyChangeEvent;
+import java.util.List;
+
 import org.glassfish.config.support.GlassFishConfigBean;
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
-import org.junit.After;
-import static org.junit.Assert.assertTrue;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
@@ -36,6 +36,13 @@
 import org.jvnet.hk2.config.Transactions;
 import org.jvnet.hk2.config.UnprocessedChangeEvents;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.fail;
+
 /**
  * User: Jerome Dochez
  * Date: Jun 24, 2008
@@ -43,90 +50,89 @@
  */
 public class TranslatedViewCreationTest extends ConfigApiTest {
 
-    final static String propName = "com.sun.my.chosen.docroot";
+    private static final String propName = "com.sun.my.chosen.docroot";
 
+    private HttpService httpService;
+    private List<PropertyChangeEvent> events;
+    private ServiceLocator locator;
+
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    HttpService httpService = null;
-    List<PropertyChangeEvent> events;
-    ServiceLocator habitat;
-
-    @Before
+    @BeforeEach
     public void setup() {
         System.setProperty(propName, "/foo/bar/docroot");
-        habitat = Utils.instance.getHabitat(this);
+        locator = Utils.instance.getHabitat(this);
+    }
 
+    @AfterEach
+    public void tearDown() {
+        System.setProperty(propName, "");
     }
 
     @Override
     public ServiceLocator getBaseServiceLocator() {
-        return habitat;
+        return locator;
     }
 
     @Test
     public void createVirtualServerTest() throws TransactionFailure {
         httpService = getHabitat().getService(HttpService.class);
         final TransactionListener listener = new TransactionListener() {
-                public void transactionCommited(List<PropertyChangeEvent> changes) {
-                    events = changes;
-                }
 
+            @Override
+            public void transactionCommited(List<PropertyChangeEvent> changes) {
+                events = changes;
+            }
+
+
+            @Override
             public void unprocessedTransactedEvents(List<UnprocessedChangeEvents> changes) {
             }
         };
 
         Transactions transactions = getHabitat().getService(Transactions.class);
-
         try {
             transactions.addTransactionsListener(listener);
-            assertTrue(httpService!=null);
-            ConfigSupport.apply(new SingleConfigCode<HttpService>() {
-
-                public Object run(HttpService param) throws PropertyVetoException, TransactionFailure {
-                    VirtualServer newVirtualServer = param.createChild(VirtualServer.class);
-                    newVirtualServer.setDocroot("${"+propName+"}");
-                    newVirtualServer.setId("translated-view-creation");
-                    param.getVirtualServer().add(newVirtualServer);
-                    return null;
-                }
-            }, httpService);
+            assertNotNull(httpService);
+            SingleConfigCode<HttpService> configCode = http -> {
+                VirtualServer newVirtualServer = http.createChild(VirtualServer.class);
+                newVirtualServer.setDocroot("${" + propName + "}");
+                newVirtualServer.setId("translated-view-creation");
+                http.getVirtualServer().add(newVirtualServer);
+                return null;
+            };
+            ConfigSupport.apply(configCode, httpService);
 
             // first let check that our new virtual server has the right translated value
             VirtualServer vs = httpService.getVirtualServerByName("translated-view-creation");
-            assertTrue(vs!=null);
+            assertNotNull(vs);
             String docRoot = vs.getDocroot();
-            assertTrue("/foo/bar/docroot".equals(docRoot));
+            assertEquals("/foo/bar/docroot", docRoot);
 
             transactions.waitForDrain();
 
-            assertTrue(events!=null);
-            logger.fine("Number of events " + events.size());
-            assertTrue(events.size()==3);
+            assertNotNull(events);
+            assertThat(events, hasSize(3));
             for (PropertyChangeEvent event : events) {
                 if ("virtual-server".equals(event.getPropertyName())) {
                     VirtualServer newVS = (VirtualServer) event.getNewValue();
-                    assertTrue(event.getOldValue()==null);
+                    assertNull(event.getOldValue());
                     docRoot = newVS.getDocroot();
-                    assertTrue("/foo/bar/docroot".equals(docRoot));
+                    assertEquals("/foo/bar/docroot", docRoot);
 
                     VirtualServer rawView = GlassFishConfigBean.getRawView(newVS);
-                    assertTrue(rawView!=null);
-                    assertTrue(rawView.getDocroot().equalsIgnoreCase("${" + propName + "}"));
+                    assertNotNull(rawView);
+                    assertEquals("${" + propName + "}", rawView.getDocroot());
                     return;
                 }
             }
-            assertTrue(false);
-
+            fail("virtual-server event wasn't found");
         } finally {
             transactions.removeTransactionsListener(listener);
         }
 
     }
-
-    @After
-    public void tearDown() {
-        System.setProperty(propName, "");
-    }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TraversalTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TraversalTest.java
deleted file mode 100644
index ed4b0f2..0000000
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/TraversalTest.java
+++ /dev/null

@@ -1,82 +0,0 @@
-/*
- * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
- *
- * This program and the accompanying materials are made available under the
- * terms of the Eclipse Public License v. 2.0, which is available at
- * http://www.eclipse.org/legal/epl-2.0.
- *
- * This Source Code may also be made available under the following Secondary
- * Licenses when the conditions for such availability set forth in the
- * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
- * version 2 with the GNU Classpath Exception, which is available at
- * https://www.gnu.org/software/classpath/license.html.
- *
- * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
- */
-
-package com.sun.enterprise.configapi.tests;
-
-import org.glassfish.hk2.api.ServiceLocator;
-import org.jvnet.hk2.config.Dom;
-import org.junit.Ignore;
-import org.junit.Test;
-
-import java.util.Set;
-import java.util.logging.Logger;
-
-import com.sun.enterprise.config.serverbeans.Domain;
-
-/**
- * Traverse a config tree using the hk2 model APIs.
- *
- * @author Jerome Dochez
- */
-public class TraversalTest extends ConfigApiTest {
-
-    static Logger logger = Logger.getAnonymousLogger();
-
-    public String getFileName() {
-        return "DomainTest";
-    }
-
-    @Test
-    public void traverse() {
-        ServiceLocator habitat = super.getHabitat();
-        Domain domain = Domain.class.cast(habitat.<Domain>getService(Domain.class));
-        introspect(0, Dom.unwrap(domain));
-    }
-
-
-    @Ignore
-    private void introspect(int indent, Dom proxy) {
-        indent = indent + 1;
-        Set<String> ss = proxy.getAttributeNames();
-        String id = "";
-        for (int i = 0; i < indent; i++) {
-            id = id + "    ";
-        }
-        logger.fine(id + "--------" + proxy.model.key);
-        for (String a : ss) {
-
-            logger.fine(id + a + "=" + proxy.attribute(a));
-        }
-
-
-        Set<String> elem = proxy.getElementNames();
-
-        for (String bb : elem) {
-
-
-            logger.fine(id + "<" + bb + ">");
-            org.jvnet.hk2.config.ConfigModel.Property prop = proxy.model.getElement(bb);
-            if (prop != null && proxy.model.getElement(bb).isLeaf()) {
-                logger.fine(proxy.leafElement(bb));
-            } else {
-                introspect(indent, proxy.element(bb));
-            }
-            logger.fine(id + "</" + bb + ">");
-            logger.fine("    ");
-
-        }
-    }
-}

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/UnprocessedEventsTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/UnprocessedEventsTest.java
index d48d030..45e64f0 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/UnprocessedEventsTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/UnprocessedEventsTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2021 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -23,10 +24,7 @@
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigListener;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.ObservableBean;
@@ -37,14 +35,18 @@
 import org.jvnet.hk2.config.UnprocessedChangeEvent;
 import org.jvnet.hk2.config.UnprocessedChangeEvents;
 
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
 /**
  * @author Jerome Dochez
  */
-public class UnprocessedEventsTest  extends ConfigApiTest
-        implements ConfigListener, TransactionListener {
+public class UnprocessedEventsTest extends ConfigApiTest implements ConfigListener, TransactionListener {
 
-    ServiceLocator habitat = Utils.instance.getHabitat(this);
-    UnprocessedChangeEvents unprocessed = null;
+    private final ServiceLocator habitat = Utils.instance.getHabitat(this);
+    private UnprocessedChangeEvents unprocessed;
 
     /**
      * Returns the DomainTest file name without the .xml extension to load the test configuration
@@ -52,6 +54,7 @@
      *
      * @return the configuration file name
      */
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
@@ -61,69 +64,64 @@
 
         // let's find our target
         NetworkConfig service = habitat.getService(NetworkConfig.class);
-        NetworkListener listener = service.getNetworkListener("http-listener-1");
-        assertNotNull(listener);
+        NetworkListener networkListener = service.getNetworkListener("http-listener-1");
+        assertNotNull(networkListener);
 
         // Let's register a listener
-        ObservableBean bean = (ObservableBean) ConfigSupport.getImpl(listener);
+        ObservableBean bean = (ObservableBean) ConfigSupport.getImpl(networkListener);
         bean.addListener(this);
         Transactions transactions = getHabitat().getService(Transactions.class);
 
         try {
             transactions.addTransactionsListener(this);
 
-            ConfigSupport.apply(new SingleConfigCode<NetworkListener>() {
-                public Object run(NetworkListener param) {
-                    param.setPort("8908");
-                    return null;
-                }
-            }, listener);
+            SingleConfigCode<NetworkListener> configCode = listener -> {
+                listener.setPort("8908");
+                return null;
+            };
+            ConfigSupport.apply(configCode, networkListener);
 
             // check the result.
-            String port = listener.getPort();
+            String port = networkListener.getPort();
             assertEquals(port, "8908");
 
             // ensure events are delivered.
             transactions.waitForDrain();
             assertNotNull(unprocessed);
 
-            ConfigSupport.apply(new SingleConfigCode<NetworkListener>() {
-                public Object run(NetworkListener param) {
-                    param.setPort("8080");
-                    return null;
-                }
-            }, listener);
-
-            assertEquals(listener.getPort(), "8080");
+            SingleConfigCode<NetworkListener> configCodeReset = listener -> {
+                listener.setPort("8080");
+                return null;
+            };
+            ConfigSupport.apply(configCodeReset, networkListener);
+            assertEquals(networkListener.getPort(), "8080");
 
             // ensure events are delivered.
             transactions.waitForDrain();
             assertNotNull(unprocessed);
-
-            // finally
             bean.removeListener(this);
         } finally {
-
-            // check we recevied the event
             transactions.removeTransactionsListener(this);
         }
 
     }
 
+    @Override
     public UnprocessedChangeEvents changed(PropertyChangeEvent[] propertyChangeEvents) {
-        assertEquals("Array size", propertyChangeEvents.length, 1 );
-
+        assertEquals(propertyChangeEvents.length, 1, "Array size");
         final UnprocessedChangeEvent unp = new UnprocessedChangeEvent(
             propertyChangeEvents[0], "Java NIO port listener cannot reconfigure its port dynamically" );
         unprocessed = new UnprocessedChangeEvents( unp );
         return unprocessed;
     }
 
+    @Override
     public void transactionCommited(List<PropertyChangeEvent> changes) {
         // don't care...
     }
 
+    @Override
     public void unprocessedTransactedEvents(List<UnprocessedChangeEvents> changes) {
-        assertTrue(changes.size()==1);
+        assertThat(changes, hasSize(1));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/VetoableChangeListenerTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/VetoableChangeListenerTest.java
index b51fc9e..6bbe1b7 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/VetoableChangeListenerTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/VetoableChangeListenerTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,19 +17,25 @@
 
 package com.sun.enterprise.configapi.tests;
 
-import org.jvnet.hk2.config.*;
-import org.jvnet.hk2.config.types.*;
-import org.jvnet.hk2.component.*;
-import org.junit.*;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
+import com.sun.enterprise.config.serverbeans.HttpService;
+import com.sun.enterprise.config.serverbeans.VirtualServer;
+
+import java.beans.PropertyChangeEvent;
+import java.beans.PropertyVetoException;
+import java.beans.VetoableChangeListener;
 
 import org.glassfish.hk2.api.ServiceLocator;
-import org.glassfish.tests.utils.*;
+import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigBean;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.ConstrainedBeanListener;
+import org.jvnet.hk2.config.SingleConfigCode;
+import org.jvnet.hk2.config.TransactionFailure;
 
-import com.sun.enterprise.config.serverbeans.*;
-
-import java.beans.*;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * This test registers an vetoable change listener on a config bean and vetoes
@@ -38,96 +45,58 @@
  */
 public class VetoableChangeListenerTest extends ConfigApiTest implements VetoableChangeListener {
 
-    ServiceLocator habitat;
-    boolean result = false;
+    private ServiceLocator locator;
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
-        habitat = Utils.instance.getHabitat(this);
+        locator = Utils.instance.getHabitat(this);
     }
 
     @Test
     public void propertyChangeEventReceptionTest() throws TransactionFailure {
-
-        HttpService httpService = habitat.getService(HttpService.class);
-        assertNotNull(httpService);
-
-       // let's find a acceptable target.
-        VirtualServer target =null;
-        for (VirtualServer vs : httpService.getVirtualServer()) {
-            if (!vs.getProperty().isEmpty()) {
-                target = vs;
-                break;
-            }
-        }
-
+        final VirtualServer target = findTargetWithProperties();
         assertNotNull(target);
 
+        SingleConfigCode<VirtualServer> configCode = vs -> {
+            vs.setId("foo");
+            vs.setAccessLog("Foo");
+            return null;
+        };
         ((ConfigBean) ConfigSupport.getImpl(target)).getOptionalFeature(ConstrainedBeanListener.class).addVetoableChangeListener(this);
-
-        try {
-            ConfigSupport.apply(new SingleConfigCode<VirtualServer>() {
-
-                public Object run(VirtualServer param) throws PropertyVetoException, TransactionFailure {
-                    param.setId("foo");
-                    param.setAccessLog("Foo");
-                    return null;
-                }
-            }, target);
-        } catch(TransactionFailure e) {
-            //e.printStackTrace();
-            System.out.println("Got exception: " + e.getClass().getName() + " as expected, with message: " + e.getMessage());
-            result=true;
-        }
-
-        assertTrue(result);
-
-        result=false;
+        assertThrows(TransactionFailure.class, () -> ConfigSupport.apply(configCode, target));
         // let's do it again.
-        try {
-            ConfigSupport.apply(new SingleConfigCode<VirtualServer>() {
-
-                public Object run(VirtualServer param) throws PropertyVetoException, TransactionFailure {
-                    param.setId("foo");
-                    param.setAccessLog("Foo");
-                    return null;
-                }
-            }, target);
-        } catch(TransactionFailure e) {
-            //e.printStackTrace();
-            System.out.println("Got exception: " + e.getClass().getName() + " as expected, with message: " + e.getMessage());
-            result=true;
-        }
-
+        assertThrows(TransactionFailure.class, () -> ConfigSupport.apply(configCode, target));
         ((ConfigBean) ConfigSupport.getImpl(target)).getOptionalFeature(ConstrainedBeanListener.class).removeVetoableChangeListener(this);
-        assertTrue(result);
 
-
-        // this time it should work !
-        try {
-            ConfigSupport.apply(new SingleConfigCode<VirtualServer>() {
-
-                public Object run(VirtualServer param) throws PropertyVetoException, TransactionFailure {
-                    // first one is fine...
-                    param.setAccessLog("Foo");
-                    return null;
-                }
-            }, target);
-        } catch(TransactionFailure e) {
-            //e.printStackTrace();
-            System.out.println("Got exception: " + e.getClass().getName() + " as expected, with message: " + e.getMessage());
-            result=false;
-        }
-
-        assertTrue(result);
+        // this time it should work!
+        SingleConfigCode<VirtualServer> configCode2 = vs -> {
+            // first one is fine...
+            vs.setAccessLog("Foo");
+            return null;
+        };
+        ConfigSupport.apply(configCode2, target);
     }
 
 
+    @Override
     public void vetoableChange(PropertyChangeEvent evt) throws PropertyVetoException {
         throw new PropertyVetoException("I don't think so !", evt);
     }
+
+
+    private VirtualServer findTargetWithProperties() {
+        HttpService httpService = locator.getService(HttpService.class);
+        assertNotNull(httpService);
+        for (VirtualServer vs : httpService.getVirtualServer()) {
+            if (!vs.getProperty().isEmpty()) {
+                return vs;
+            }
+        }
+        return null;
+    }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/cluster/DuckMethodsTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/cluster/DuckMethodsTest.java
index 99967bf..fdb7805 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/cluster/DuckMethodsTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/cluster/DuckMethodsTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,17 +17,18 @@
 
 package com.sun.enterprise.configapi.tests.cluster;
 
+import com.sun.enterprise.config.serverbeans.Cluster;
 import com.sun.enterprise.config.serverbeans.Domain;
 import com.sun.enterprise.config.serverbeans.Server;
-import com.sun.enterprise.config.serverbeans.Cluster;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
 
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
-import org.junit.Before;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
 
 /**
  * Test a number of cluster related {@link org.jvnet.hk2.config.DuckTyped}
@@ -35,24 +37,25 @@
  * @author Jerome Dochez
  */
 public class DuckMethodsTest extends ConfigApiTest {
-    ServiceLocator habitat;
+    private ServiceLocator locator;
 
+    @Override
     public String getFileName() {
         return "ClusterDomain";
     }
 
-    @Before
+    @BeforeEach
     public void setup() {
-        habitat = Utils.instance.getHabitat(this);
+        locator = Utils.instance.getHabitat(this);
     }
 
 
     @Test
     public void getClusterFromServerTest() {
-        Domain d = habitat.getService(Domain.class);
+        Domain d = locator.getService(Domain.class);
         Server server = d.getServerNamed("server");
-        assertTrue(server!=null);
+        assertNotNull(server);
         Cluster cluster = server.getCluster();
-        System.out.println("Cluster name is " + cluster.getName());
+        assertEquals("clusterA", cluster.getName());
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/concurrent/ConcurrentAccessTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/concurrent/ConcurrentAccessTest.java
index f61011a..0c66c05 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/concurrent/ConcurrentAccessTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/concurrent/ConcurrentAccessTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2010, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -18,49 +19,40 @@
 
 import com.sun.enterprise.config.serverbeans.Domain;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
-import org.junit.Test;
+
+import java.util.concurrent.Semaphore;
+
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 
-import java.beans.PropertyVetoException;
-import java.util.concurrent.Semaphore;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 
 /**
  * Concurrent access to the configuarion APIs related tests
  * @author Jerome Dochez
  */
-
 public class ConcurrentAccessTest extends ConfigApiTest {
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
 
     @Test
-    public void waitAndSuccessTest() throws TransactionFailure, InterruptedException {
-        ConfigSupport.lockTimeOutInSeconds=1;
+    public void waitAndSuccessTest() throws Exception {
+        ConfigSupport.lockTimeOutInSeconds = 1;
         runTest(200);
     }
 
-    @Test(expected=TransactionFailure.class)
-    public void waitAndTimeOutTest() throws TransactionFailure, InterruptedException {
-        ConfigSupport.lockTimeOutInSeconds=1;
-        try {
-            runTest(1200);
-        } catch (TransactionFailure transactionFailure) {
-            logger.fine("Got expected transaction failure, access timed out");
-            throw transactionFailure;
-        } catch (InterruptedException e) {
-            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
-            throw e;
-        }
+    @Test
+    public void waitAndTimeOutTest() throws Exception {
+        ConfigSupport.lockTimeOutInSeconds = 1;
+        assertThrows(TransactionFailure.class, () -> runTest(1200));
     }
 
-
-
-    private void runTest(final int waitTime) throws TransactionFailure, InterruptedException {
-
+    private void runTest(final int waitTime) throws Exception {
         final Domain domain = getHabitat().getService(Domain.class);
 
         // my lock.
@@ -72,53 +64,43 @@
         endOfAccess.acquire();
 
         final long begin = System.currentTimeMillis();
-
+        final SingleConfigCode<Domain> configCode = domain1 -> {
+            logger.fine("got the lock at " + (System.currentTimeMillis() - begin));
+            lock.release();
+            try {
+                Thread.sleep(waitTime);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+            logger.fine("release the lock at " + (System.currentTimeMillis() - begin));
+            return null;
+        };
         // let's start a thread to hold the lock on Domain...
-        Thread t = new Thread(new Runnable() {
-            @Override
-            public void run() {
-                try {
-                    ConfigSupport.apply(new SingleConfigCode<Domain>() {
-                        @Override
-                        public Object run(Domain domain) throws PropertyVetoException, TransactionFailure {
-                            logger.fine("got the lock at " + (System.currentTimeMillis() - begin));
-                            lock.release();
-                            try {
-                                Thread.sleep(waitTime);
-                            } catch (InterruptedException e) {
-                                e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
-                            }
-                            logger.fine("release the lock at " + (System.currentTimeMillis() - begin));
-                            return null;
-                        };
-                    }, domain);
-                } catch(TransactionFailure e) {
-                    e.printStackTrace();
-                }
+        Runnable job = () -> {
+            try {
+                ConfigSupport.apply(configCode, domain);
+            } catch (TransactionFailure e) {
+                e.printStackTrace();
+            } finally {
                 endOfAccess.release();
             }
-        });
+        };
+        final Thread t = new Thread(job);
         t.start();
 
-
         // let's change the last modified date...
         lock.acquire();
         logger.fine("looking for second lock at " + (System.currentTimeMillis() - begin));
 
+        final SingleConfigCode<Domain> releaseLockCode = domain1 -> {
+            logger.fine("got the second lock at " + (System.currentTimeMillis() - begin));
+            lock.release();
+            return null;
+        };
         try {
-            ConfigSupport.apply(new SingleConfigCode<Domain>() {
-                @Override
-                public Object run(Domain domain) throws PropertyVetoException, TransactionFailure {
-                    logger.fine("got the second lock at " + (System.currentTimeMillis() - begin));
-                    lock.release();
-                    return null;
-                }
-            }, domain);
+            ConfigSupport.apply(releaseLockCode, domain);
         } finally {
             endOfAccess.acquire();
         }
-
-
     }
-
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/AccessLogAllDefaultsTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/AccessLogAllDefaultsTest.java
index d479b9e..9bf9dd8 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/AccessLogAllDefaultsTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/AccessLogAllDefaultsTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -14,45 +15,39 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  */
 
-/*
- * To change this template, choose Tools | Templates
- * and open the template in the editor.
- */
-
 package com.sun.enterprise.configapi.tests.dvt;
 
 import com.sun.enterprise.config.serverbeans.AccessLog;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import static org.junit.Assert.*;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 /**
- *
  * @author kedar
  */
 public class AccessLogAllDefaultsTest extends ConfigApiTest {
 
-    private AccessLog al = null;
-
-    public AccessLogAllDefaultsTest() {
-    }
+    private AccessLog al;
 
     @Override
     public String getFileName() {
         return ("AccessLogAllDefaultsTest"); //this is the xml to load
     }
 
-    @Before
+    @BeforeEach
     public void setUp() {
         al = super.getHabitat().getService(AccessLog.class);
     }
 
-    @After
+    @AfterEach
     public void tearDown() {
         al = null;
     }
+
     @Test
     public void testAllDefaults() {
         assertEquals("true", al.getRotationEnabled());

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/SecurityServiceDefaultsTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/SecurityServiceDefaultsTest.java
index ba4ff44..aa9661a 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/SecurityServiceDefaultsTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/dvt/SecurityServiceDefaultsTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -18,48 +19,43 @@
 
 import com.sun.enterprise.config.serverbeans.SecurityService;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import static org.junit.Assert.*;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 /**
  * Tests the JdbcConnectionPool config bean's defaults.
  * @author Kedar Mhaswade (km@dev.java.net)
  */
-
 public class SecurityServiceDefaultsTest extends ConfigApiTest {
 
-    SecurityService ss = null;
-
-    public SecurityServiceDefaultsTest() {
-    }
+    private SecurityService securityService;
 
     @Override
     public String getFileName() {
-        return ("SecurityServiceDefaults"); //this is the xml to load
+        return "SecurityServiceDefaults"; //this is the xml to load
     }
 
-    @Before
+    @BeforeEach
     public void setUp() {
-        ss = super.getHabitat().getService(SecurityService.class);
+        securityService = super.getHabitat().getService(SecurityService.class);
     }
 
-    @After
+    @AfterEach
     public void tearDown() {
-        ss = null;
+        securityService = null;
     }
 
-    // TODO add test methods here.
-    // The methods must be annotated with annotation @Test. For example:
-    //
     @Test
     public void testFewDefaults() {
-        assertEquals("file", ss.getDefaultRealm());
-        assertEquals("true", ss.getActivateDefaultPrincipalToRoleMapping());
-        assertEquals("AttributeDeprecated", ss.getAnonymousRole());
-        assertEquals("false", ss.getAuditEnabled());
-        assertEquals("default", ss.getAuditModules());
-        assertEquals("default", ss.getJacc());
+        assertEquals("file", securityService.getDefaultRealm());
+        assertEquals("true", securityService.getActivateDefaultPrincipalToRoleMapping());
+        assertEquals("AttributeDeprecated", securityService.getAnonymousRole());
+        assertEquals("false", securityService.getAuditEnabled());
+        assertEquals("default", securityService.getAuditModules());
+        assertEquals("default", securityService.getJacc());
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/AnApplicationExtension.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/AnApplicationExtension.java
similarity index 90%
rename from nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/AnApplicationExtension.java
rename to nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/AnApplicationExtension.java
index 6007987..38c2f2a 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/AnApplicationExtension.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/AnApplicationExtension.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2011, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -14,10 +15,10 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  */
 
-package com.sun.enterprise.configapi.tests.extensibility;
+package com.sun.enterprise.configapi.tests.example;
 
 import com.sun.enterprise.config.serverbeans.ApplicationExtension;
-import org.junit.Ignore;
+
 import org.jvnet.hk2.config.Attribute;
 import org.jvnet.hk2.config.Configured;
 

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpListenerContainer.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/HttpListenerContainer.java
similarity index 83%
rename from nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpListenerContainer.java
rename to nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/HttpListenerContainer.java
index 256c2bd..759f498 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/HttpListenerContainer.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/HttpListenerContainer.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2008, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -14,15 +15,12 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  */
 
-package com.sun.enterprise.configapi.tests;
+package com.sun.enterprise.configapi.tests.example;
 
 import java.beans.PropertyChangeEvent;
 
 import org.glassfish.grizzly.config.dom.NetworkListener;
 import org.glassfish.hk2.api.PerLookup;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
 import org.jvnet.hk2.annotations.Service;
 import org.jvnet.hk2.config.ConfigListener;
 import org.jvnet.hk2.config.UnprocessedChangeEvents;
@@ -30,20 +28,25 @@
 import jakarta.inject.Inject;
 import jakarta.inject.Named;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 /**
  * Simple container code that is interested in getting notification of injected model changes
  *
  * @author Jerome Dochez
  */
-@Service @PerLookup
+@Service
+@PerLookup
 public class HttpListenerContainer implements ConfigListener {
 
     @Inject
     @Named("http-listener-1")
-    NetworkListener httpListener;
+    public NetworkListener httpListener;
 
-    volatile boolean received=false;
+    public volatile boolean received = false;
 
+    @Override
     public synchronized UnprocessedChangeEvents changed(PropertyChangeEvent[] events) {
         if (received) {
             // I am alredy happy

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomContainer.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomContainer.java
similarity index 79%
rename from nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomContainer.java
rename to nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomContainer.java
index a0ad0df..6dcc240 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomContainer.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomContainer.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -14,13 +15,13 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  */
 
-package com.sun.enterprise.configapi.tests.extensibility;
+package com.sun.enterprise.configapi.tests.example;
 
 import org.glassfish.api.admin.config.Container;
 import org.glassfish.api.admin.config.Named;
 import org.jvnet.hk2.config.Attribute;
-import org.jvnet.hk2.config.Element;
 import org.jvnet.hk2.config.Configured;
+import org.jvnet.hk2.config.Element;
 
 /**
  * @author Jerome Dochez
@@ -29,12 +30,12 @@
 public interface RandomContainer extends Container, Named {
 
     @Attribute
-    public String getNumberOfRuntime();
+    String getNumberOfRuntime();
 
-    public void setNumberOfRuntime();
+    void setNumberOfRuntime();
 
     @Element
-    public RandomElement getRandomElement();
+    RandomElement getRandomElement();
 
-    public void setRandomElement(RandomElement randomElement);
+    void setRandomElement(RandomElement randomElement);
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomElement.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomElement.java
similarity index 84%
rename from nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomElement.java
rename to nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomElement.java
index 2e4fc72..7b8fe53 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomElement.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomElement.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -14,12 +15,11 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  */
 
-package com.sun.enterprise.configapi.tests.extensibility;
+package com.sun.enterprise.configapi.tests.example;
 
-import org.jvnet.hk2.config.Configured;
-import org.jvnet.hk2.config.ConfigBeanProxy;
 import org.jvnet.hk2.config.Attribute;
-import org.glassfish.api.admin.config.Named;
+import org.jvnet.hk2.config.ConfigBeanProxy;
+import org.jvnet.hk2.config.Configured;
 
 /**
  * @author Jerome Dochez
@@ -28,7 +28,7 @@
 public interface RandomElement extends ConfigBeanProxy {
 
     @Attribute
-    public String getAttr1();
+    String getAttr1();
 
-    public void setAttr1(String string);
+    void setAttr1(String string);
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomExtension.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomExtension.java
similarity index 89%
rename from nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomExtension.java
rename to nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomExtension.java
index b627544..53c78fd 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/RandomExtension.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/example/RandomExtension.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2010, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -14,7 +15,7 @@
  * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
  */
 
-package com.sun.enterprise.configapi.tests.extensibility;
+package com.sun.enterprise.configapi.tests.example;
 
 import org.glassfish.api.admin.config.ConfigExtension;
 import org.jvnet.hk2.config.Attribute;

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/ContainerExtensionTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/ContainerExtensionTest.java
index aebcc39..d6a70e1 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/ContainerExtensionTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/extensibility/ContainerExtensionTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2009, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -17,17 +18,26 @@
 package com.sun.enterprise.configapi.tests.extensibility;
 
 import com.sun.enterprise.config.serverbeans.Application;
-import com.sun.enterprise.configapi.tests.ConfigApiTest;
 import com.sun.enterprise.config.serverbeans.Config;
 import com.sun.enterprise.config.serverbeans.Domain;
-import org.glassfish.tests.utils.Utils;
-import org.glassfish.api.admin.config.Container;
-import org.glassfish.hk2.api.ServiceLocator;
-import org.junit.Test;
-import static org.junit.Assert.*;
+import com.sun.enterprise.configapi.tests.ConfigApiTest;
+import com.sun.enterprise.configapi.tests.example.AnApplicationExtension;
+import com.sun.enterprise.configapi.tests.example.RandomContainer;
+import com.sun.enterprise.configapi.tests.example.RandomElement;
+import com.sun.enterprise.configapi.tests.example.RandomExtension;
 
 import java.util.List;
 
+import org.glassfish.api.admin.config.Container;
+import org.glassfish.hk2.api.ServiceLocator;
+import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
 /**
  * @author Jerome Dochez
  */
@@ -43,10 +53,9 @@
 
     @Test
     public void existenceTest() {
-
         Config config = habitat.<Domain>getService(Domain.class).getConfigs().getConfig().get(0);
         List<Container> containers = config.getContainers();
-        assertTrue(containers.size()==2);
+        assertThat(containers, hasSize(2));
         RandomContainer container = (RandomContainer) containers.get(0);
         assertEquals("random", container.getName());
         assertEquals("1243", container.getNumberOfRuntime());
@@ -67,6 +76,6 @@
     public void applicationExtensionTest() {
         Application a = habitat.getService(Application.class);
         List<AnApplicationExtension> taes = a.getExtensionsByType(AnApplicationExtension.class);
-        assertEquals(taes.size(), 2);
+        assertThat(taes, hasSize(2));
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/model/.gitkeep_empty_dir b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/model/.gitkeep_empty_dir
deleted file mode 100644
index e69de29..0000000
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/model/.gitkeep_empty_dir
+++ /dev/null


diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/typedlistener/TypedListenerTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/typedlistener/TypedListenerTest.java
index 10b48ca..a437b06 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/typedlistener/TypedListenerTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/typedlistener/TypedListenerTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2011, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -19,16 +20,22 @@
 import com.sun.enterprise.config.serverbeans.Domain;
 import com.sun.enterprise.config.serverbeans.SystemProperty;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
+
 import java.beans.PropertyChangeEvent;
-import java.beans.PropertyVetoException;
 import java.util.Arrays;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicInteger;
-import java.util.logging.Level;
-import static org.junit.Assert.assertNotNull;
-import static org.junit.Assert.assertTrue;
-import org.junit.Test;
-import org.jvnet.hk2.config.*;
+import org.junit.jupiter.api.Test;
+import org.jvnet.hk2.config.ConfigListener;
+import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.SingleConfigCode;
+import org.jvnet.hk2.config.TransactionFailure;
+import org.jvnet.hk2.config.Transactions;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.hasSize;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * Test the listeners per type registration/events/un-registration.
@@ -36,8 +43,8 @@
  */
 public class TypedListenerTest extends ConfigApiTest {
 
-    List<PropertyChangeEvent> events = null;
-    AtomicInteger listenersInvoked = new AtomicInteger();
+    private List<PropertyChangeEvent> events;
+    private final AtomicInteger listenersInvoked = new AtomicInteger();
 
     @Override
     public String getFileName() {
@@ -46,40 +53,30 @@
 
     @Test
     public void addElementTest() throws TransactionFailure {
-
         final Domain domain = getHabitat().getService(Domain.class);
-        final ConfigListener configListener = new ConfigListener() {
-            @Override
-            public UnprocessedChangeEvents changed(PropertyChangeEvent[] propertyChangeEvents) {
-                events = Arrays.asList(propertyChangeEvents);
-                return null;
-            }
+        final ConfigListener configListener = propertyChangeEvents -> {
+            events = Arrays.asList(propertyChangeEvents);
+            return null;
         };
 
         Transactions transactions = getHabitat().getService(Transactions.class);
-
         try {
             transactions.addListenerForType(SystemProperty.class, configListener);
 
-            assertTrue(domain!=null);
+            assertNotNull(domain);
 
             // adding
-            ConfigSupport.apply(new SingleConfigCode<Domain>() {
-
-                        @Override
-                        public Object run(Domain domain) throws PropertyVetoException, TransactionFailure {
-                            SystemProperty prop = domain.createChild(SystemProperty.class);
-                            domain.getSystemProperty().add(prop);
-                            prop.setName("Jerome");
-                            prop.setValue("was here");
-                            return prop;
-                        }
-                    }, domain);
+            SingleConfigCode<Domain> configCode = domain1 -> {
+                SystemProperty sysProp = domain1.createChild(SystemProperty.class);
+                domain1.getSystemProperty().add(sysProp);
+                sysProp.setName("Jerome");
+                sysProp.setValue("was here");
+                return sysProp;
+            };
+            ConfigSupport.apply(configCode, domain);
             transactions.waitForDrain();
 
-            assertTrue(events!=null);
-            logger.log(Level.FINE, "Number of events {0}", events.size());
-            assertTrue(events.size()==3);
+            assertThat(events, hasSize(3));
             for (PropertyChangeEvent event : events) {
                 logger.fine(event.toString());
             }
@@ -87,20 +84,16 @@
 
             // modification
             for (SystemProperty prop : domain.getSystemProperty()) {
-                if (prop.getName().equals("Jerome")) {
-                    ConfigSupport.apply(new SingleConfigCode<SystemProperty>() {
-                                @Override
-                                public Object run(SystemProperty param) throws PropertyVetoException, TransactionFailure {
-                                    param.setValue("was also here");
-                                    return null;
-                                }
-                            },prop);
+                if ("Jerome".equals(prop.getName())) {
+                    SingleConfigCode<SystemProperty> configCode2 = sysProp -> {
+                        sysProp.setValue("was also here");
+                        return null;
+                    };
+                    ConfigSupport.apply(configCode2, prop);
                     break;
                 }
             }
-            assertTrue(events!=null);
-            logger.log(Level.FINE, "Number of events {0}", events.size());
-            assertTrue(events.size()==1);
+            assertThat(events, hasSize(1));
             for (PropertyChangeEvent event : events) {
                 logger.fine(event.toString());
             }
@@ -108,24 +101,19 @@
             events = null;
 
             // removal
-            assertNotNull(ConfigSupport.apply(new SingleConfigCode<Domain>() {
-
-                        @Override
-                        public Object run(Domain domain) throws PropertyVetoException, TransactionFailure {
-                            for (SystemProperty prop : domain.getSystemProperty()) {
-                                if (prop.getName().equals("Jerome")) {
-                                    domain.getSystemProperty().remove(prop);
-                                    return prop;
-                                }
-                            }
-                            return null;
-                        }
-                    }, domain));
+            SingleConfigCode<Domain> configCode2 = domain1 -> {
+                for (SystemProperty prop : domain1.getSystemProperty()) {
+                    if ("Jerome".equals(prop.getName())) {
+                        domain1.getSystemProperty().remove(prop);
+                        return prop;
+                    }
+                }
+                return null;
+            };
+            assertNotNull(ConfigSupport.apply(configCode2, domain));
             transactions.waitForDrain();
 
-            assertTrue(events!=null);
-            logger.log(Level.FINE, "Number of events {0}", events.size());
-            assertTrue(events.size()==1);
+            assertThat(events, hasSize(1));
             for (PropertyChangeEvent event : events) {
                 logger.fine(event.toString());
             }
@@ -137,41 +125,31 @@
     @Test
     public void multipleListeners() throws TransactionFailure {
         final Domain domain = getHabitat().getService(Domain.class);
-        final ConfigListener configListener1 = new ConfigListener() {
-            @Override
-            public UnprocessedChangeEvents changed(PropertyChangeEvent[] propertyChangeEvents) {
-                listenersInvoked.incrementAndGet();
-                return null;
-            }
+        assertNotNull(domain);
+
+        final ConfigListener configListener1 = propertyChangeEvents -> {
+            listenersInvoked.incrementAndGet();
+            return null;
         };
-        final ConfigListener configListener2 = new ConfigListener() {
-            @Override
-            public UnprocessedChangeEvents changed(PropertyChangeEvent[] propertyChangeEvents) {
-                listenersInvoked.incrementAndGet();
-                return null;
-            }
+        final ConfigListener configListener2 = propertyChangeEvents -> {
+            listenersInvoked.incrementAndGet();
+            return null;
         };
 
         Transactions transactions = getHabitat().getService(Transactions.class);
-
         try {
             transactions.addListenerForType(SystemProperty.class, configListener1);
             transactions.addListenerForType(SystemProperty.class, configListener2);
 
-            assertTrue(domain!=null);
-
             // adding
-            ConfigSupport.apply(new SingleConfigCode<Domain>() {
-
-                        @Override
-                        public Object run(Domain domain) throws PropertyVetoException, TransactionFailure {
-                            SystemProperty prop = domain.createChild(SystemProperty.class);
-                            domain.getSystemProperty().add(prop);
-                            prop.setName("Jerome");
-                            prop.setValue("was here");
-                            return prop;
-                        }
-                    }, domain);
+            SingleConfigCode<Domain> configCode = domain1 -> {
+                SystemProperty prop = domain1.createChild(SystemProperty.class);
+                domain1.getSystemProperty().add(prop);
+                prop.setName("Jerome");
+                prop.setValue("was here");
+                return prop;
+            };
+            ConfigSupport.apply(configCode, domain);
             transactions.waitForDrain();
 
             assertTrue(listenersInvoked.intValue()==2);

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/FieldsValidationTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/FieldsValidationTest.java
index 63ee830..a63ef38 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/FieldsValidationTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/FieldsValidationTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2010, 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -18,21 +19,27 @@
 
 import com.sun.enterprise.config.serverbeans.AdminService;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
-import junit.framework.Assert;
-import org.junit.Test;
+
+import java.beans.PropertyVetoException;
+
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigSupport;
 import org.jvnet.hk2.config.SingleConfigCode;
 import org.jvnet.hk2.config.TransactionFailure;
 
 import jakarta.validation.ConstraintViolationException;
-import java.beans.PropertyVetoException;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.instanceOf;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.fail;
 
 /**
  * Test Field validation
  */
-
 public class FieldsValidationTest extends ConfigApiTest {
 
+    @Override
     public String getFileName() {
         return "DomainTest";
     }
@@ -40,7 +47,7 @@
     @Test
     public void testNotNullField() {
         AdminService admin = super.getHabitat().getService(AdminService.class);
-        Assert.assertNotNull(admin);
+        assertNotNull(admin);
         try {
             ConfigSupport.apply(new SingleConfigCode<AdminService>() {
                 @Override
@@ -49,11 +56,9 @@
                     return null;
                 }
             }, admin);
-            Assert.fail("Exception not raised when setting a @NotNull annotated field with null");
+            fail("Exception not raised when setting a @NotNull annotated field with null");
         } catch(TransactionFailure e) {
-            if (e.getCause()!=null) {
-                Assert.assertTrue(e.getCause() instanceof ConstraintViolationException);
-            }
+            assertThat(e.getCause(), instanceOf(ConstraintViolationException.class));
         }
     }
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainClusterTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainClusterTest.java
index fec0a1f..d8632c9 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainClusterTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainClusterTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2012, 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -19,27 +20,30 @@
 import com.sun.enterprise.config.serverbeans.Cluster;
 import com.sun.enterprise.config.serverbeans.ServerRef;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
+
 import java.util.HashMap;
 import java.util.Map;
-import jakarta.validation.ConstraintViolationException;
-import org.junit.Test;
-import org.junit.Before;
+
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigBean;
 import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
 import org.jvnet.hk2.config.TransactionFailure;
 
-import static org.junit.Assert.*;
+import jakarta.validation.ConstraintViolationException;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.fail;
 
 /**
- *
  * @author mmares
  */
 public class ReferenceConstrainClusterTest extends ConfigApiTest {
 
-//    private Logger logger = Logger.getLogger(ReferenceConstrainTest.class.getName());
-    private ServiceLocator habitat;
+    private ServiceLocator locator;
 
     @Override
     public String getFileName() {
@@ -48,7 +52,7 @@
 
     @Override
     public ServiceLocator getBaseServiceLocator() {
-        return habitat;
+        return locator;
     }
 
     private ConstraintViolationException findConstrViolation(Throwable thr) {
@@ -61,19 +65,33 @@
         return findConstrViolation(thr.getCause());
     }
 
-    @Before
+    @BeforeEach
     public void createNewHabitat() {
-        this.habitat = Utils.instance.getHabitat(this);
+        this.locator = Utils.instance.getHabitat(this);
+    }
+
+    @Test
+    public void clusterServerRefValid() throws TransactionFailure {
+        Cluster cluster = locator.getService(Cluster.class, "clusterA");
+        assertNotNull(cluster);
+        ServerRef sref = cluster.getServerRef().get(0);
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(sref);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
+        configChanges.put("ref", "server");
+        changes.put(serverConfig, configChanges);
+        ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
+        cs.apply(changes);
     }
 
     @Test
     public void clusterServerRefInvalid() throws TransactionFailure {
-        Cluster cluster = habitat.getService(Cluster.class, "clusterA");
+        Cluster cluster = locator.getService(Cluster.class, "clusterA");
         assertNotNull(cluster);
         ServerRef sref = cluster.getServerRef().get(0);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(sref);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(sref);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
         configChanges.put("ref", "server-nonexist");
         changes.put(serverConfig, configChanges);
         try {
@@ -87,30 +105,25 @@
     }
 
     @Test
-    public void clusterServerRefValid() throws TransactionFailure {
-        Cluster cluster = habitat.getService(Cluster.class, "clusterA");
+    public void clusterConfigRefValid() throws TransactionFailure {
+        Cluster cluster = locator.getService(Cluster.class, "clusterA");
         assertNotNull(cluster);
-        ServerRef sref = cluster.getServerRef().get(0);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(sref);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
-        configChanges.put("ref", "server");
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(cluster);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
+        configChanges.put("config-ref", "server-config");
         changes.put(serverConfig, configChanges);
-        try {
-            ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
-            cs.apply(changes);
-        } catch (TransactionFailure tf) {
-            fail("Can not reach this point");
-        }
+        ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
+        cs.apply(changes);
     }
 
     @Test
     public void clusterConfigRefInvalid() throws TransactionFailure {
-        Cluster cluster = habitat.getService(Cluster.class, "clusterA");
+        Cluster cluster = locator.getService(Cluster.class, "clusterA");
         assertNotNull(cluster);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(cluster);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(cluster);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
         configChanges.put("config-ref", "server-config-nonexist");
         changes.put(serverConfig, configChanges);
         try {
@@ -122,22 +135,4 @@
             assertNotNull(cv);
         }
     }
-
-    @Test
-    public void clusterConfigRefValid() throws TransactionFailure {
-        Cluster cluster = habitat.getService(Cluster.class, "clusterA");
-        assertNotNull(cluster);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(cluster);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
-        configChanges.put("config-ref", "server-config");
-        changes.put(serverConfig, configChanges);
-        try {
-            ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
-            cs.apply(changes);
-        } catch (TransactionFailure tf) {
-            fail("Can not reach this point");
-        }
-    }
-
 }

diff --git a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainTest.java b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainTest.java
index b406181..fcbf233 100644
--- a/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainTest.java
+++ b/nucleus/admin/config-api/src/test/java/com/sun/enterprise/configapi/tests/validation/ReferenceConstrainTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2012, 2020 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -19,18 +20,23 @@
 import com.sun.enterprise.config.serverbeans.JmxConnector;
 import com.sun.enterprise.config.serverbeans.Server;
 import com.sun.enterprise.configapi.tests.ConfigApiTest;
+
 import java.util.HashMap;
 import java.util.Map;
-import jakarta.validation.ConstraintViolationException;
-import org.junit.Test;
-import org.junit.Before;
+
 import org.glassfish.hk2.api.ServiceLocator;
 import org.glassfish.tests.utils.Utils;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hk2.config.ConfigBean;
 import org.jvnet.hk2.config.ConfigSupport;
+import org.jvnet.hk2.config.Dom;
 import org.jvnet.hk2.config.TransactionFailure;
 
-import static org.junit.Assert.*;
+import jakarta.validation.ConstraintViolationException;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.fail;
 
 /**
  *
@@ -38,8 +44,7 @@
  */
 public class ReferenceConstrainTest extends ConfigApiTest {
 
-//    private Logger logger = Logger.getLogger(ReferenceConstrainTest.class.getName());
-    private ServiceLocator habitat;
+    private ServiceLocator locator;
 
     @Override
     public String getFileName() {
@@ -48,7 +53,7 @@
 
     @Override
     public ServiceLocator getBaseServiceLocator() {
-        return habitat;
+        return locator;
     }
 
     private ConstraintViolationException findConstrViolation(Throwable thr) {
@@ -61,18 +66,31 @@
         return findConstrViolation(thr.getCause());
     }
 
-    @Before
+    @BeforeEach
     public void createNewHabitat() {
-        this.habitat = Utils.instance.getHabitat(this);
+        this.locator = Utils.instance.getHabitat(this);
+    }
+
+    @Test
+    public void serverConfigRefValid() throws TransactionFailure {
+        Server server = locator.getService(Server.class, "server");
+        assertNotNull(server);
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(server);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
+        configChanges.put("config-ref", "server-config");
+        changes.put(serverConfig, configChanges);
+        ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
+        cs.apply(changes);
     }
 
     @Test
     public void serverConfigRefInvalid() throws TransactionFailure {
-        Server server = habitat.getService(Server.class, "server");
+        Server server = locator.getService(Server.class, "server");
         assertNotNull(server);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(server);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(server);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
         configChanges.put("config-ref", "server-config-nonexist");
         changes.put(serverConfig, configChanges);
         try {
@@ -86,29 +104,25 @@
     }
 
     @Test
-    public void serverConfigRefValid() throws TransactionFailure {
-        Server server = habitat.getService(Server.class, "server");
-        assertNotNull(server);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(server);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
-        configChanges.put("config-ref", "server-config");
+    public void jmxConnectorAuthRealmRefValid() throws TransactionFailure {
+        JmxConnector jmxConnector = locator.getService(JmxConnector.class, "system");
+        assertNotNull(jmxConnector);
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(jmxConnector);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
+        configChanges.put("auth-realm-name", "file");
         changes.put(serverConfig, configChanges);
-        try {
-            ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
-            cs.apply(changes);
-        } catch (TransactionFailure tf) {
-            fail("Can not reach this point");
-        }
+        ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
+        cs.apply(changes);
     }
 
     @Test
     public void jmxConnectorAuthRealmRefInvalid() throws TransactionFailure {
-        JmxConnector jmxConnector = habitat.getService(JmxConnector.class, "system");
+        JmxConnector jmxConnector = locator.getService(JmxConnector.class, "system");
         assertNotNull(jmxConnector);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(jmxConnector);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
+        ConfigBean serverConfig = (ConfigBean) Dom.unwrap(jmxConnector);
+        Map<ConfigBean, Map<String, String>> changes = new HashMap<>();
+        Map<String, String> configChanges = new HashMap<>();
         configChanges.put("auth-realm-name", "realm-not-exist");
         changes.put(serverConfig, configChanges);
         try {
@@ -121,21 +135,4 @@
         }
     }
 
-    @Test
-    public void jmxConnectorAuthRealmRefValid() throws TransactionFailure {
-        JmxConnector jmxConnector = habitat.getService(JmxConnector.class, "system");
-        assertNotNull(jmxConnector);
-        ConfigBean serverConfig = (ConfigBean) ConfigBean.unwrap(jmxConnector);
-        Map<ConfigBean, Map<String, String>> changes = new HashMap<ConfigBean, Map<String, String>>();
-        Map<String, String> configChanges = new HashMap<String, String>();
-        configChanges.put("auth-realm-name", "file");
-        changes.put(serverConfig, configChanges);
-        try {
-            ConfigSupport cs = getHabitat().getService(ConfigSupport.class);
-            cs.apply(changes);
-        } catch (TransactionFailure tf) {
-            fail("Can not reach this point");
-        }
-    }
-
 }

diff --git a/nucleus/admin/config-api/src/test/java/org/glassfish/config/support/DomainXmlPreParserTest.java b/nucleus/admin/config-api/src/test/java/org/glassfish/config/support/DomainXmlPreParserTest.java
index 3f17c02..e437c98 100644
--- a/nucleus/admin/config-api/src/test/java/org/glassfish/config/support/DomainXmlPreParserTest.java
+++ b/nucleus/admin/config-api/src/test/java/org/glassfish/config/support/DomainXmlPreParserTest.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2010, 2018 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021 Contributors to the Eclipse Foundation
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -16,28 +17,35 @@
 
 package org.glassfish.config.support;
 
-import java.io.*;
-import java.net.*;
-import java.util.*;
+import java.net.URL;
+import java.util.List;
+
 import javax.xml.stream.XMLInputFactory;
+
 import org.glassfish.config.support.DomainXmlPreParser.DomainXmlPreParserException;
-import org.junit.After;
-import org.junit.AfterClass;
-import org.junit.Before;
-import org.junit.BeforeClass;
-import org.junit.Test;
-import static org.junit.Assert.*;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.startsWith;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.fail;
 
 /**
- *
  * @author bnevins
  */
 public class DomainXmlPreParserTest {
 
-    public DomainXmlPreParserTest() {
-    }
+    private static URL stock, i1, i1i2, c1i1, c1i1c1i2, noconfigfori1;
+    private static ClassLoader classLoader = DomainXmlPreParserTest.class.getClassLoader();
+    private static XMLInputFactory xif = XMLInputFactory.newInstance();
 
-    @BeforeClass
+    @BeforeAll
     public static void setUpClass() throws Exception {
         stock = loadURL("parser/stock.xml");
         i1 = loadURL("parser/i1.xml");
@@ -54,22 +62,10 @@
         return url;
     }
 
-    @AfterClass
-    public static void tearDownClass() throws Exception {
-    }
-
-    @Before
-    public void setUp() {
-    }
-
-    @After
-    public void tearDown() {
-    }
-
-    @Test(expected=DomainXmlPreParser.DomainXmlPreParserException.class)
+    @Test
     public void stockDomainHasNoInstance() throws DomainXmlPreParserException {
         System.out.println("stockDomainHasNoInstance");
-        DomainXmlPreParser pp = new DomainXmlPreParser(stock, xif, "i1");
+        assertThrows(DomainXmlPreParserException.class, () -> new DomainXmlPreParser(stock, xif, "i1"));
     }
 
     @Test
@@ -80,10 +76,10 @@
         String clusterName = pp.getClusterName();
         String configName = pp.getConfigName();
 
-        assertTrue(servers.size() == 1);
-        assertTrue(servers.get(0).equals("i1"));
+        assertThat(servers, hasSize(1));
+        assertEquals("i1", servers.get(0));
         assertNull(clusterName);
-        assertEquals(configName, "i1-config");
+        assertEquals("i1-config", configName);
     }
 
     @Test
@@ -94,11 +90,10 @@
         String clusterName = pp.getClusterName();
         String configName = pp.getConfigName();
 
-        assertTrue(servers.size() == 1);
-        assertTrue(servers.contains("i1"));
-        assertFalse(servers.contains("i2"));
+        assertThat(servers, hasSize(1));
+        assertThat(servers, contains("i1"));
         assertNull(clusterName);
-        assertEquals(configName, "i1-config");
+        assertEquals("i1-config", configName);
     }
 
     @Test
@@ -109,11 +104,10 @@
         String clusterName = pp.getClusterName();
         String configName = pp.getConfigName();
 
-        assertTrue(servers.size() == 1);
-        assertTrue(servers.contains("i2"));
-        assertFalse(servers.contains("i1"));
+        assertThat(servers, hasSize(1));
+        assertThat(servers, contains("i2"));
         assertNull(clusterName);
-        assertEquals(configName, "i2-config");
+        assertEquals("i2-config", configName);
     }
 
     @Test
@@ -124,10 +118,10 @@
         String clusterName = pp.getClusterName();
         String configName = pp.getConfigName();
 
-        assertTrue(servers.size() == 1);
-        assertTrue(servers.contains("c1i1"));
-        assertEquals(clusterName, "c1");
-        assertEquals(configName, "c1-config");
+        assertThat(servers, hasSize(1));
+        assertThat(servers, contains("c1i1"));
+        assertEquals("c1", clusterName);
+        assertEquals("c1-config", configName);
     }
 
     @Test
@@ -138,27 +132,20 @@
         String clusterName = pp.getClusterName();
         String configName = pp.getConfigName();
 
-        assertTrue(servers.size() == 2);
-        assertTrue(servers.contains("c1i1"));
-        assertTrue(servers.contains("c1i2"));
-        assertEquals(clusterName, "c1");
-        assertEquals(configName, "c1-config");
+        assertThat(servers, hasSize(2));
+        assertThat(servers, contains("c1i1", "c1i2"));
+        assertEquals("c1", clusterName);
+        assertEquals("c1-config", configName);
     }
 
     @Test
     public void noConfigTest() {
         System.out.println("noConfigTest");
         try {
-            DomainXmlPreParser pp = new DomainXmlPreParser(noconfigfori1, xif, "i1");
+            new DomainXmlPreParser(noconfigfori1, xif, "i1");
             fail("Expected an exception!!!");
-        }
-        catch(DomainXmlPreParserException e) {
-            assertTrue(e.getMessage().startsWith("The config element, "));
-            System.out.println(e);
+        } catch (DomainXmlPreParserException e) {
+            assertThat(e.getMessage(), startsWith("The config element, "));
         }
     }
-
-    private static URL stock, i1, i1i2, c1i1, c1i1c1i2, noconfigfori1;
-    private static ClassLoader classLoader = DomainXmlPreParserTest.class.getClassLoader();
-    private static XMLInputFactory xif = XMLInputFactory.newInstance();
 }