jdk8-mips64-public/jaxws: src/share/jaxws_classes/com/sun/xml/internal/ws/api/server/AsyncProvider.java@9c07ef4934dd

     1 /*

     2  * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    26 package com.sun.xml.internal.ws.api.server;

    28 import com.sun.istack.internal.NotNull;

    30 import javax.xml.ws.Provider;

    31 import javax.xml.ws.WebServiceContext;

    32 import java.util.concurrent.Executor;

    34 /**

    35  * Asynchronous version of {@link Provider}.

    36  *

    37  * <p>

    38  * Applications that use the JAX-WS RI can implement this interface instead of

    39  * {@link Provider} to implement asynchronous web services (AWS.) AWS enables

    40  * applications to perform operations with long latency without blocking a thread,

    41  * and thus particularly suitable for highly scalable service implementation,

    42  * at the expesnce of implementation complexity.

    43  *

    44  * <h2>Programming Model</h2>

    45  * <p>

    46  * Whenever a new reuqest arrives, the JAX-WS RI invokes the {@link #invoke} method

    47  * to notify the application. Normally, the application then schedules an execution

    48  * of this request, and exit from this method immediately (the point of AWS is not

    49  * to use this calling thread for request processing.)

    50  *

    51  * <p>

    52  * Unlike the synchronous version, which requires the response to be given as the return value,

    53  * with AWS the JAX-WS RI will keep the connection with client open, until the application

    54  * eventually notifies the JAX-WS RI via {@link AsyncProviderCallback}. When that

    55  * happens that causes the JAX-WS RI to send back a response to the client.

    56  *

    57  * <p>

    58  * The following code shows a very simple AWS example:

    59  *

    60  * <pre>

    61  * &#64;WebService

    62  * class MyAsyncEchoService implements AsyncProvider&lt;Source> {

    63  *     private static final {@link Executor} exec = ...;

    64  *

    65  *     public void invoke( final Source request, final AsyncProviderCallback&lt;Source> callback, final WebServiceContext context) {

    66  *         exec.execute(new {@link Runnable}() {

    67  *             public void run() {

    68  *                 Thread.sleep(1000);     // kill time.

    69  *                 callback.send(request); // just echo back

    70  *             }

    71  *         });

    72  *     }

    73  * }

    74  * </pre>

    75  *

    76  * <p>

    77  * Please also check the {@link Provider} and its programming model for general

    78  * provider programming model.

    79  *

    80  *

    81  * <h2>WebServiceContext</h2>

    82  * <p>

    83  * In synchronous web services, the injected {@link WebServiceContext} instance uses

    84  * the calling {@link Thread} to determine which request it should return information about.

    85  * This no longer works with AWS, as you may need to call {@link WebServiceContext}

    86  * much later, possibly from entirely different thread.

    87  *

    88  * <p>

    89  * For this reason, {@link AsyncProvider} passes in {@link WebServiceContext} as

    90  * a parameter. This object remains usable until you invoke {@link AsyncProviderCallback},

    91  * and it can be invoked from any thread, even concurrently. AWS must not use the injected

    92  * {@link WebServiceContext}, as its behavior is undefined.

    93  *

    94  * @see Provider

    95  * @author Jitendra Kotamraju

    96  * @author Kohsuke Kawaguchi

    97  * @since 2.1

    98  */

    99 public interface AsyncProvider<T> {

   100     /**

   101      * Schedules an execution of a request.

   102      *

   103      * @param request

   104      *      Represents the request message or payload.

   105      * @param callback

   106      *      Application must notify this callback interface when the processing

   107      *      of a request is complete.

   108      * @param context

   109      *      The web service context instance that can be used to retrieve

   110      *      context information about the given request.

   111      */

   112     public void invoke(

   113         @NotNull T request,

   114         @NotNull AsyncProviderCallback<T> callback,

   115         @NotNull WebServiceContext context);

   116 }

Mercurial > jdk8-mips64-public > jaxws / file revision