javax.ws.rs.container.Suspended Maven / Gradle / Ivy
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 2012 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* http://glassfish.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package javax.ws.rs.container;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.util.concurrent.TimeUnit;
/**
* Inject a suspended {@link AsyncResponse} into a parameter of an invoked
* JAX-RS {@link javax.ws.rs.HttpMethod resource or sub-resource method}.
*
* The injected {@code AsyncResponse} instance is bound to the processing
* of the active request and can be used to resume the request processing when
* a response is available.
*
* By default there is {@link AsyncResponse#NO_TIMEOUT no suspend timeout set} and
* the asynchronous response is suspended indefinitely. The suspend timeout as well
* as a custom {@link TimeoutHandler timeout handler} can be specified programmatically
* using the {@link AsyncResponse#setTimeout(long, TimeUnit)} and
* {@link AsyncResponse#setTimeoutHandler(TimeoutHandler)} methods. For example:
*
*
* @Stateless
* @Path("/")
* public class MyEjbResource {
* …
* @GET
* @Asynchronous
* public void longRunningOperation(@Suspended AsyncResponse ar) {
* ar.setTimeoutHandler(customHandler);
* ar.setTimeout(10, TimeUnit.SECONDS);
* final String result = executeLongRunningOperation();
* ar.resume(result);
* }
*
* private String executeLongRunningOperation() { … }
* }
*
*
* A resource or sub-resource method that injects a suspended instance of an
* {@code AsyncResponse} using the {@code @Suspended} annotation is expected
* be declared to return {@code void} type. Methods that inject asynchronous
* response instance using the {@code @Suspended} annotation and declare a
* return type other than {@code void} MUST be detected by the JAX-RS runtime and
* a warning message MUST be logged. Any response value returned from such resource
* or sub-resource method MUST be ignored by the framework:
*
*
* @Path("/messages/next")
* public class MessagingResource {
* …
* @GET
* public String readMessage(@Suspended AsyncResponse ar) {
* suspended.put(ar);
* return "This response will be ignored.";
* }
* …
* }
*
*
* @author Marek Potociar
* @since 2.0
*/
@Target({ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Suspended {
}