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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.cluster.hasingleton.service.ejb;
18  
19  import javax.annotation.Resource;
20  import javax.ejb.ScheduleExpression;
21  import javax.ejb.Singleton;
22  import javax.ejb.Timeout;
23  import javax.ejb.Timer;
24  import javax.ejb.TimerConfig;
25  import javax.ejb.TimerService;
26  
27  import org.jboss.logging.Logger;
28  
29  
30  /**
31   * A simple example to demonstrate a implementation of a cluster-wide singleton timer.
32   *
33   * @author <a href="mailto:wfink@redhat.com">Wolf-Dieter Fink</a>
34   */
35  @Singleton
36  public class SchedulerBean implements Scheduler {
37      private static Logger LOGGER = Logger.getLogger(SchedulerBean.class);
38      @Resource
39      private TimerService timerService;
40  
41      @Timeout
42      public void scheduler(Timer timer) {
43          LOGGER.info("HASingletonTimer: Info=" + timer.getInfo());
44      }
45  
46      @Override
47      public void initialize(String info) {
48          ScheduleExpression sexpr = new ScheduleExpression();
49          // set schedule to every 10 seconds for demonstration
50          sexpr.hour("*").minute("*").second("0/10");
51          // persistent must be false because the timer is started by the HASingleton service
52          timerService.createCalendarTimer(sexpr, new TimerConfig(info, false));
53      }
54  
55      @Override
56      public void stop() {
57          LOGGER.info("Stop all existing HASingleton timers");
58          for (Timer timer : timerService.getTimers()) {
59              LOGGER.trace("Stop HASingleton timer: " + timer.getInfo());
60              timer.cancel();
61          }
62      }
63  }