wamblee.org Git - utils/blob - support/test/org/wamblee/concurrency/JvmLockTest.java

   1 /*
   2  * Copyright 2005 the original author or authors.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *      http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package org.wamblee.concurrency;
  18
  19 import org.wamblee.test.EventTracker;
  20 import org.wamblee.test.TimingUtils;
  21
  22 import junit.framework.TestCase;
  23
  24 /**
  25  * Tests for the JVMLock.
  26  */
  27 public class JvmLockTest extends TestCase {
  28
  29     private static final int SLEEP_TIME = 1000;
  30
  31     private static final String STARTED = "started";
  32
  33     private static final String ACQUIRED = "acquired";
  34
  35     private static final String RELEASED = "released";
  36
  37     private JvmLock _lock;
  38
  39     private EventTracker<String> _tracker;
  40
  41     /*
  42      * (non-Javadoc)
  43      *
  44      * @see junit.framework.TestCase#setUp()
  45      */
  46     @Override
  47     protected void setUp() throws Exception {
  48         _lock = new JvmLock();
  49         _tracker = new EventTracker<String>();
  50     }
  51
  52     private Thread runThread() {
  53         Thread t = new Thread(new Runnable() {
  54             public void run() {
  55                 _tracker.eventOccurred(STARTED);
  56                 _lock.acquire();
  57                 _tracker.eventOccurred(ACQUIRED);
  58                 TimingUtils.sleep(SLEEP_TIME);
  59                 _lock.release();
  60                 _tracker.eventOccurred(RELEASED);
  61             };
  62         });
  63         t.start();
  64         return t;
  65     }
  66
  67     /**
  68      * Tests the operation of the lock.
  69      */
  70     public void testLock() throws InterruptedException {
  71         Thread t1 = runThread();
  72         Thread t2 = runThread();
  73         TimingUtils.sleep(SLEEP_TIME / 10); // give threads a chance to start
  74         // up.
  75         assertEquals(2, _tracker.getEventCount(STARTED)); // both threads
  76         // should have
  77         // started.
  78         assertEquals(1, _tracker.getEventCount(ACQUIRED)); // one thread has
  79                                                             // acquired the
  80                                                             // lock.
  81         TimingUtils.sleep(SLEEP_TIME);
  82         assertEquals(2, _tracker.getEventCount(ACQUIRED)); // now the other
  83                                                             // thread could also
  84                                                             // acquire the lock
  85         assertEquals(1, _tracker.getEventCount(RELEASED)); // and the first
  86                                                             // thread has
  87                                                             // released it.
  88         TimingUtils.sleep(SLEEP_TIME);
  89         assertEquals(2, _tracker.getEventCount(RELEASED)); // both threads
  90                                                             // should be
  91                                                             // finished.
  92         t1.join();
  93         t2.join();
  94     }
  95 }