test/jdk/java/lang/Class/getEnclosingClass/EnclosingClassTest.java

/*
 * Copyright (c) 2004, 2021, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 4992173 4992170
 * @library /test/lib
 * @modules jdk.compiler
 * @run testng/othervm EnclosingClassTest
 * @summary Check getEnclosingClass and other methods
 * @author Peter von der Ahé
 */

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.nio.file.Files;
import java.nio.file.Path;

import common.TestMe;
import jdk.test.lib.compiler.CompilerUtils;
import jdk.test.lib.util.FileUtils;
import org.testng.Assert;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;

/*
 * We have five kinds of classes:
 * a) Top level classes
 * b) Nested classes (static member classes)
 * c) Inner classes (non-static member classes)
 * d) Local classes (named classes declared within a method)
 * e) Anonymous classes
 *
 * Each one can be within a package or not.
 * Kinds b-e can/must be within kinds a-e.
 * This gives us a three dimensional space:
 * 1. dimension: b-e
 * 2. dimension: a-e
 * 3. dimension: packages
 *
 * We make a two dimensional matrix of (b-e)x(a-e) and change the
 * package configuration on that:
 *
 *   b c d e
 * a x x x x
 * b x x x x
 * c o x x x  where o means "not legal"
 * d o x x x
 * e o x x x
 */

public class EnclosingClassTest {
    private static final String SRC_DIR = System.getProperty("test.src");
    private static final Path ENCLOSING_CLASS_SRC = Path.of(SRC_DIR, "EnclosingClass.java");
    private static final String GEN_SRC_DIR = "gensrc";

    @BeforeClass
    public void createEnclosingClasses() throws IOException {
        Path pkg1Dir = Path.of(GEN_SRC_DIR, "pkg1");
        Path pkg2Dir = Path.of(GEN_SRC_DIR, "pkg1", "pkg2");
        Path pkg1File = pkg1Dir.resolve("EnclosingClass.java");
        Path pkg2File = pkg2Dir.resolve("EnclosingClass.java");

        if (!Files.notExists(pkg1Dir)) {
            FileUtils.deleteFileTreeWithRetry(pkg1Dir);
        }
        Files.createDirectories(pkg2Dir);
        createAndWriteEnclosingClasses(ENCLOSING_CLASS_SRC, pkg1File, "pkg1");
        createAndWriteEnclosingClasses(ENCLOSING_CLASS_SRC, pkg2File, "pkg1.pkg2");

        Assert.assertTrue(CompilerUtils.compile(ENCLOSING_CLASS_SRC, Path.of(System.getProperty("test.classes")),
                "--source-path", SRC_DIR));
        Assert.assertTrue(CompilerUtils.compile(pkg1File, Path.of(System.getProperty("test.classes")),
                "-classpath", System.getProperty("test.class.path")));
        Assert.assertTrue(CompilerUtils.compile(pkg2File, Path.of(System.getProperty("test.classes")),
                        "-classpath", System.getProperty("test.class.path")));
    }

    @Test
    public void testEnclosingClasses() throws ClassNotFoundException, NoSuchMethodException, IllegalAccessException,
            InvocationTargetException, InstantiationException {
        test(Class.forName("EnclosingClass").getDeclaredConstructor().newInstance());
    }

    @Test
    public void testEnclosingClassesInPackage() throws ClassNotFoundException, NoSuchMethodException,
            IllegalAccessException, InvocationTargetException, InstantiationException {
        test(Class.forName("pkg1.EnclosingClass").getDeclaredConstructor().newInstance());
    }

    @Test
    public void testEnclosingClassesInNestedPackage() throws ClassNotFoundException, NoSuchMethodException,
            IllegalAccessException, InvocationTargetException, InstantiationException {
        test(Class.forName("pkg1.pkg2.EnclosingClass").getDeclaredConstructor().newInstance());
    }

    private void createAndWriteEnclosingClasses(Path source, Path target, String packageName) throws IOException {
        String className = packageName + ".EnclosingClass";
        try (BufferedReader br = new BufferedReader(new FileReader(source.toFile()));
        PrintWriter bw = new PrintWriter(new FileWriter(target.toFile()))) {
            String line;
            while ((line = br.readLine()) != null) {
                if (line.contains("canonical=\"EnclosingClass")) {
                    line = line.replaceAll("canonical=\"EnclosingClass", "canonical=\"" + className);
                } else if (line.contains("\"class EnclosingClass")) {
                    line = line.replaceAll("\"class EnclosingClass", "\"class " + className);
                } else if (line.contains("//package")) {
                    line = line.replaceAll("//package", "package " + packageName + ";");
                }
                bw.println(line);
            }
        }
    }

    private void info(Class<?> c, Class<?> encClass, String desc) {
        if (!"".equals(desc)) {
            System.out.println(desc + ":");
        }
        System.out.println(c);
        System.out.println("\tis enclosed by:\t\t" + encClass);
        System.out.println("\thas simple name:\t`" +
                           c.getSimpleName() + "'");
        System.out.println("\thas canonical name:\t`" +
                           c.getCanonicalName() + "'");
    }

    private void match(String actual, String expected) {
        Assert.assertTrue((actual == null && expected == null) || actual.equals(expected));
        System.out.println("\t`" +
                           actual + "' matches expected `" +
                           expected + "'");
    }

    private void check(Class<?> c, Class<?> enc,
                       String encName, String encNameExpected,
                       String simpleName, String simpleNameExpected,
                       String canonicalName, String canonicalNameExpected) {
        match(encName, encNameExpected);
        match(simpleName, simpleNameExpected);
        match(canonicalName, canonicalNameExpected);
    }

    private void testClass(Class<?> c, TestMe annotation, Field f) {
        if (Void.class.equals(c))
            return;
        Class<?> encClass = c.getEnclosingClass();
        c.getEnclosingMethod(); // make sure it does not crash
        c.getEnclosingConstructor(); // make sure it does not crash
        info(c, encClass, annotation.desc());
        check(c, encClass,
              ""+encClass, annotation.encl(),
              c.getSimpleName(), annotation.simple(),
              c.getCanonicalName(),
              annotation.hasCanonical() ? annotation.canonical() : null);
        if (void.class.equals(c))
            return;
        Class<?> array = java.lang.reflect.Array.newInstance(c, 0).getClass();
        check(array, array.getEnclosingClass(),
              "", "",
              array.getSimpleName(), annotation.simple()+"[]",
              array.getCanonicalName(),
              annotation.hasCanonical() ? annotation.canonical()+"[]" : null);
    }

    private void test(Object tests) {
        for (Field f : tests.getClass().getFields()) {
            TestMe annotation = f.getAnnotation(TestMe.class);
            if (annotation != null) {
                try {
                    testClass((Class<?>)f.get(tests), annotation, f);
                } catch (AssertionError ex) {
                    System.err.println("Error in " +
                                       tests.getClass().getName() +
                                       "." + f.getName());
                    throw ex;
                } catch (IllegalAccessException ex) {
                    ex.printStackTrace();
                    throw new RuntimeException(ex);
                }
            }
        }
    }
}