View Javadoc
1   /*
2    * JBoss, Home of Professional Open Source
3    * Copyright 2014, Red Hat, Inc. and/or its affiliates, and individual
4    * contributors by the @authors tag. See the copyright.txt in the
5    * distribution for a full listing of individual contributors.
6    *
7    * Licensed under the Apache License, Version 2.0 (the "License");
8    * you may not use this file except in compliance with the License.
9    * You may obtain a copy of the License at
10   * http://www.apache.org/licenses/LICENSE-2.0
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  package org.jboss.as.quickstarts.servlet.async;
18  
19  import java.io.PrintWriter;
20  import java.text.SimpleDateFormat;
21  import java.util.Date;
22  import java.util.logging.Level;
23  import java.util.logging.Logger;
24  
25  import javax.ejb.Asynchronous;
26  import javax.ejb.Stateless;
27  import javax.servlet.AsyncContext;
28  
29  /**
30   * A simple service to simulate the execution of a long running task.
31   * 
32   * @author Christian Sadilek <csadilek@redhat.com>
33   */
34  @Stateless
35  public class LongRunningService {
36  
37      private final Logger logger = Logger.getLogger(LongRunningService.class.getName());
38  
39      /**
40       * The use of {@link Asynchronous} causes this EJB method to be executed asynchronously, by a different thread from a
41       * dedicated, container managed thread pool.
42       * 
43       * @param asyncContext the context for a suspended Servlet request that this EJB will complete later.
44       */
45      @Asynchronous
46      public void readData(AsyncContext asyncContext) {
47          try {
48              // This is just to simulate a long running operation for demonstration purposes.
49              Thread.sleep(5000);
50  
51              PrintWriter writer = asyncContext.getResponse().getWriter();
52              writer.println(new SimpleDateFormat("HH:mm:ss").format(new Date()));
53              writer.close();
54  
55              asyncContext.complete();
56          } catch (Exception e) {
57              logger.log(Level.SEVERE, e.getMessage(), e);
58          }
59      }
60  }