| /* |
| * Copyright (c) 2015, 2019 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 org.glassfish.jersey.spi; |
| |
| import java.util.concurrent.ExecutorService; |
| |
| /** |
| * An extension contract for providing pluggable executor service providers to be used by |
| * Jersey client or server runtime whenever a specific executor service is needed to execute a Jersey runtime processing task. |
| * <p> |
| * This mechanism allows Jersey to run in environments that have specific thread management and provisioning requirements, |
| * such as application servers, cloud environments etc. |
| * Dedicated Jersey extension modules or applications running in such environment may provide a custom |
| * implementation of the {@code ExecutorServiceProvider} interface to customize the default |
| * Jersey runtime thread management & provisioning strategy in order to comply with the threading requirements, |
| * models and policies specific to each particular environment. |
| * </p> |
| * <p> |
| * When Jersey runtime no longer requires the use of a provided executor service instance, it invokes the provider's |
| * {@link #dispose} method to signal the provider that the executor service instance can be disposed of. In this method, |
| * provider is free to implement the proper shut-down logic for the disposed executor service instance and perform other |
| * necessary cleanup. Yet, some providers may wish to implement a shared executor service strategy. In such case, |
| * it may not be desirable to shut down the released executor service in the {@link #dispose} method. Instead, to perform the |
| * eventual shut-down procedure, the provider may either rely on an explicit invocation of it's specific clean-up method. |
| * Since all Jersey providers operate in a <em>container</em> environment, a good clean-up strategy for a shared executor |
| * service provider implementation is to expose a {@link javax.annotation.PreDestroy @PreDestroy}-annotated method |
| * that will be invoked for all instances managed by the container, before the container shuts down. |
| * </p> |
| * <p> |
| * IMPORTANT: Please note that any pre-destroy methods may not be invoked for instances created outside of the container |
| * and later registered within the container. Pre-destroy methods are only guaranteed to be invoked for those instances |
| * that are created and managed by the container. |
| * </p> |
| * <p> |
| * Jersey runtime expects that a concrete executor service provider implementation class is annotated with a |
| * {@link javax.inject.Qualifier qualifier} annotation. This qualifier is then used to createAndInitialize a qualified injection point |
| * for injecting the executor service instance provided by the annotated provider. {@link javax.inject.Named Named} providers |
| * are also supported. For example: |
| * </p> |
| * <pre> |
| * @Named("my-executor") |
| * public MyExecutorProvider implements ExecutorServiceProvider { |
| * ... |
| * } |
| * |
| * ... |
| * |
| * // Injecting ExecutorService provided by the MyExecutorProvider |
| * @Inject @Named("my-executor") ExecutorService myExecutor; |
| * </pre> |
| * |
| * @author Marek Potociar |
| * @see ScheduledExecutorServiceProvider |
| * @see ThreadPoolExecutorProvider |
| * @since 2.18 |
| */ |
| @Contract |
| public interface ExecutorServiceProvider { |
| |
| /** |
| * Get an executor service to be used by Jersey client or server runtime to execute specific tasks. |
| * <p> |
| * This method is <em>usually</em> invoked just once at either Jersey client or server application runtime initialization, |
| * it <em>may</em> however be invoked multiple times. Once the instance of the provided executor service is not |
| * needed anymore by Jersey application runtime, it will be {@link #dispose disposed}. |
| * This typically happens in one of the following situations: |
| * </p> |
| * <ul> |
| * <li>Jersey client instance is closed (client runtime is shut down).</li> |
| * <li>Jersey container running a server-side Jersey application is shut down.</li> |
| * <li>Jersey server-side application is un-deployed.</li> |
| * </ul> |
| * |
| * @return an executor service. Must not return {@code null}. |
| */ |
| public ExecutorService getExecutorService(); |
| |
| /** |
| * Invoked when Jersey runtime no longer requires use of the provided executor service. |
| * |
| * @param executorService executor service to be disposed. |
| */ |
| public void dispose(ExecutorService executorService); |
| } |