api/src/main/java/jakarta/annotation/PostConstruct.java

/*
 * Copyright (c) 2005, 2020 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 jakarta.annotation;

import java.lang.annotation.*;
import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.*;

/**
 * The <code>PostConstruct</code> annotation is used on a method that 
 * needs to be executed after dependency injection is done to perform 
 * any initialization. This  method must be invoked before the class 
 * is put into service. This annotation must be supported on all classes 
 * that support dependency injection. The method annotated with 
 * <code>PostConstruct</code> must be invoked even if the class does 
 * not request any resources to be injected. Only one 
 * method in a given class can be annotated with this annotation. 
 * The method on which the <code>PostConstruct</code> annotation is 
 * applied must fulfill all of the following criteria:
 * <ul>
 * <li>The method must not have any parameters except in the case of 
 * interceptors in which case it takes an <code>InvocationContext</code>
 * object as defined by the Jakarta Interceptors specification.</li>
 * <li>The method defined on an interceptor class or superclass of an
 * interceptor class must have one of the following signatures:
 * <p>
 * void &#060;METHOD&#062;(InvocationContext)
 * <p>
 * Object &#060;METHOD&#062;(InvocationContext) throws Exception
 * <p>
 * <i>Note: A PostConstruct interceptor method must not throw application 
 * exceptions, but it may be declared to throw checked exceptions including 
 * the java.lang.Exception if the same interceptor method interposes on 
 * business or timeout methods in addition to lifecycle events. If a 
 * PostConstruct interceptor method returns a value, it is ignored by 
 * the container.</i>
 * </li>
 * <li>The method defined on a non-interceptor class must have the 
 * following signature:
 * <p>
 * void &#060;METHOD&#062;()
 * </li>
 * <li>The method on which the <code>PostConstruct</code> annotation
 * is applied may be public, protected, package private or private.</li>
 * <li>The method must not be static except for the application client.</li>
 * <li>The method should not be final.</li>
 * <li>If the method throws an unchecked exception the class must not be put into   
 * service except in the case where the exception is handled by an
 * interceptor.</li></ul>
 *
 * @see jakarta.annotation.PreDestroy
 * @see jakarta.annotation.Resource
 * @since 1.6, Common Annotations 1.0
 */
@Documented
@Retention (RUNTIME)
@Target(METHOD)
public @interface PostConstruct {
}