|
1 package org.jboss.cache.lock;
2
3 import EDU.oswego.cs.dl.util.concurrent.ReadWriteLock;
4 import EDU.oswego.cs.dl.util.concurrent.ReentrantWriterPreferenceReadWriteLock;
5 import junit.framework.Test;
6 import junit.framework.TestCase;
7 import junit.framework.TestSuite;
8
9
14 public class ReadWriteLockTest extends TestCase {
15 ReadWriteLock lock;
16 Exception  ex=null;
17
18
19 protected void setUp() throws Exception {
20 super.setUp();
21 ex=null;
22 }
23
24 protected void tearDown() throws Exception {
25 super.tearDown();
26 lock=null;
27 if(ex != null)
28 throw ex;
29 }
30
31
32 public void testMoreWriteReleasesThanAcquisitions() throws InterruptedException {
33 lock=new ReentrantWriterPreferenceReadWriteLock();
34 lock.writeLock().acquire();
35 lock.writeLock().release();
36 lock.writeLock().release();
37 }
38
39 public void testMoreReadReleasesThanAcquisitions() throws InterruptedException {
40 lock=new ReentrantWriterPreferenceReadWriteLock();
41 lock.readLock().acquire();
42 lock.readLock().release();
43 try {
44 lock.readLock().release();
45 fail("read locks cannot be released more than acquired");
46 }
47 catch(IllegalStateException illegalStateEx) {
48
49 }
50 }
51
52 public void testSimple() throws InterruptedException {
53 lock=new ReentrantWriterPreferenceReadWriteLock();
54 lock.readLock().acquire();
55 lock.readLock().acquire();
56 lock.writeLock().acquire();
57 lock.writeLock().acquire();
58 }
59
60
61 public void testOneWriterMultipleReaders() throws InterruptedException {
62 lock=new ReentrantWriterPreferenceReadWriteLock();
63
64 Writer writer=new Writer("writer");
65 Reader reader1=new Reader("reader1");
66 Reader reader2=new Reader("reader2");
67
68 writer.start();
69 reader1.start();
70 reader2.start();
71
72 writer.join();
73 reader1.join();
74 reader2.join();
75 }
76
77 class Writer extends Thread {
78
79 public Writer(String name) {
80 super(name);
81 }
82
83 public void run() {
84 try {
85 log("acquiring WL");
86 lock.writeLock().acquire();
87 log("acquired WL successfully");
88 sleep(1000);
89 }
90 catch(InterruptedException e) {
91 ex=e;
92 }
93 finally {
94 log("releasing WL");
95 lock.writeLock().release();
96 }
97 }
98 }
99
100
101 class Reader extends Thread {
102
103 public Reader(String name) {
104 super(name);
105 }
106
107
108 public void run() {
109 try {
110 log("acquiring RL");
111 lock.readLock().acquire();
112 log("acquired RL successfully");
113 sleep(500);
114 }
115 catch(InterruptedException e) {
116 ex=e;
117 }
118 finally {
119 log("releasing RL");
120 lock.readLock().release();
121 }
122 }
123 }
124
125 static void log(String msg) {
126 System.out.println(Thread.currentThread().getName() + ": " + msg);
127 }
128
129 public static Test suite() {
130 return new TestSuite(ReadWriteLockTest.class);
131 }
132
133 public static void main(String [] args) {
134 junit.textui.TestRunner.run(suite());
135 }
136
137 }
138 |
Popular Tags |
Java API By Example, From Geeks To Geeks.