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1
7 package org.jboss.cache.tests;
8
9 import EDU.oswego.cs.dl.util.concurrent.ReadWriteLock;
10 import EDU.oswego.cs.dl.util.concurrent.ReentrantWriterPreferenceReadWriteLock;
11 import junit.framework.Test;
12 import junit.framework.TestCase;
13 import junit.framework.TestSuite;
14
15
20 public class ReadWriteLockTest extends TestCase {
21 ReadWriteLock lock;
22 Exception  ex=null;
23
24
25 protected void setUp() throws Exception {
26 super.setUp();
27 ex=null;
28 }
29
30 protected void tearDown() throws Exception {
31 super.tearDown();
32 lock=null;
33 if(ex != null)
34 throw ex;
35 }
36
37
38 public void testMoreWriteReleasesThanAcquisitions() throws InterruptedException {
39 lock=new ReentrantWriterPreferenceReadWriteLock();
40 lock.writeLock().acquire();
41 lock.writeLock().release();
42 lock.writeLock().release();
43 }
44
45 public void testMoreReadReleasesThanAcquisitions() throws InterruptedException {
46 lock=new ReentrantWriterPreferenceReadWriteLock();
47 lock.readLock().acquire();
48 lock.readLock().release();
49 try {
50 lock.readLock().release();
51 fail("read locks cannot be released more than acquired");
52 }
53 catch(IllegalStateException illegalStateEx) {
54
55 }
56 }
57
58 public void testSimple() throws InterruptedException {
59 lock=new ReentrantWriterPreferenceReadWriteLock();
60 lock.readLock().acquire();
61 lock.readLock().acquire();
62 lock.writeLock().acquire();
63 lock.writeLock().acquire();
64 }
65
66
67 public void testOneWriterMultipleReaders() throws InterruptedException {
68 lock=new ReentrantWriterPreferenceReadWriteLock();
69
70 Writer writer=new Writer("writer");
71 Reader reader1=new Reader("reader1");
72 Reader reader2=new Reader("reader2");
73
74 writer.start();
75 reader1.start();
76 reader2.start();
77
78 writer.join();
79 reader1.join();
80 reader2.join();
81 }
82
83 class Writer extends Thread {
84
85 public Writer(String name) {
86 super(name);
87 }
88
89 public void run() {
90 try {
91 log("acquiring WL");
92 lock.writeLock().acquire();
93 log("acquired WL successfully");
94 sleep(1000);
95 }
96 catch(InterruptedException e) {
97 ex=e;
98 }
99 finally {
100 log("releasing WL");
101 lock.writeLock().release();
102 }
103 }
104 }
105
106
107 class Reader extends Thread {
108
109 public Reader(String name) {
110 super(name);
111 }
112
113
114 public void run() {
115 try {
116 log("acquiring RL");
117 lock.readLock().acquire();
118 log("acquired RL successfully");
119 sleep(500);
120 }
121 catch(InterruptedException e) {
122 ex=e;
123 }
124 finally {
125 log("releasing RL");
126 lock.readLock().release();
127 }
128 }
129 }
130
131
132 static void sleep(long timeout) {
133 try {
134 Thread.sleep(timeout);
135 }
136 catch(InterruptedException e) {
137 }
138 }
139
140 static void log(String msg) {
141 System.out.println(Thread.currentThread().getName() + ": " + msg);
142 }
143
144 public static Test suite() {
145 return new TestSuite(ReadWriteLockTest.class);
146 }
147
148 public static void main(String [] args) {
149 junit.textui.TestRunner.run(suite());
150 }
151
152 }
153 |
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