1 |
/* |
2 |
* Written by members of JCP JSR-166 Expert Group and released to the |
3 |
* public domain. Use, modify, and redistribute this code in any way |
4 |
* without acknowledgement. Other contributors include Andrew Wright, |
5 |
* Jeffrey Hayes, Pat Fischer, Mike Judd. |
6 |
*/ |
7 |
|
8 |
import junit.framework.*; |
9 |
import java.util.*; |
10 |
import java.util.concurrent.*; |
11 |
|
12 |
public class CountDownLatchTest extends JSR166TestCase { |
13 |
public static void main(String[] args) { |
14 |
junit.textui.TestRunner.run (suite()); |
15 |
} |
16 |
public static Test suite() { |
17 |
return new TestSuite(CountDownLatchTest.class); |
18 |
} |
19 |
|
20 |
/** |
21 |
* negative constructor argument throws IAE |
22 |
*/ |
23 |
public void testConstructor() { |
24 |
try { |
25 |
new CountDownLatch(-1); |
26 |
shouldThrow(); |
27 |
} catch(IllegalArgumentException success){} |
28 |
} |
29 |
|
30 |
/** |
31 |
* getCount returns initial count and decreases after countDown |
32 |
*/ |
33 |
public void testGetCount() { |
34 |
final CountDownLatch l = new CountDownLatch(2); |
35 |
assertEquals(2, l.getCount()); |
36 |
l.countDown(); |
37 |
assertEquals(1, l.getCount()); |
38 |
} |
39 |
|
40 |
/** |
41 |
* countDown decrements count when positive and has no effect when zero |
42 |
*/ |
43 |
public void testCountDown() { |
44 |
final CountDownLatch l = new CountDownLatch(1); |
45 |
assertEquals(1, l.getCount()); |
46 |
l.countDown(); |
47 |
assertEquals(0, l.getCount()); |
48 |
l.countDown(); |
49 |
assertEquals(0, l.getCount()); |
50 |
} |
51 |
|
52 |
/** |
53 |
* await returns after countDown to zero, but not before |
54 |
*/ |
55 |
public void testAwait() { |
56 |
final CountDownLatch l = new CountDownLatch(2); |
57 |
|
58 |
Thread t = new Thread(new Runnable() { |
59 |
public void run() { |
60 |
try { |
61 |
threadAssertTrue(l.getCount() > 0); |
62 |
l.await(); |
63 |
threadAssertTrue(l.getCount() == 0); |
64 |
} catch(InterruptedException e){ |
65 |
threadUnexpectedException(); |
66 |
} |
67 |
} |
68 |
}); |
69 |
t.start(); |
70 |
try { |
71 |
assertEquals(l.getCount(), 2); |
72 |
Thread.sleep(SHORT_DELAY_MS); |
73 |
l.countDown(); |
74 |
assertEquals(l.getCount(), 1); |
75 |
l.countDown(); |
76 |
assertEquals(l.getCount(), 0); |
77 |
t.join(); |
78 |
} catch (InterruptedException e){ |
79 |
unexpectedException(); |
80 |
} |
81 |
} |
82 |
|
83 |
|
84 |
/** |
85 |
* timed await returns after countDown to zero |
86 |
*/ |
87 |
public void testTimedAwait() { |
88 |
final CountDownLatch l = new CountDownLatch(2); |
89 |
|
90 |
Thread t = new Thread(new Runnable() { |
91 |
public void run() { |
92 |
try { |
93 |
threadAssertTrue(l.getCount() > 0); |
94 |
threadAssertTrue(l.await(SMALL_DELAY_MS, TimeUnit.MILLISECONDS)); |
95 |
} catch(InterruptedException e){ |
96 |
threadUnexpectedException(); |
97 |
} |
98 |
} |
99 |
}); |
100 |
t.start(); |
101 |
try { |
102 |
assertEquals(l.getCount(), 2); |
103 |
Thread.sleep(SHORT_DELAY_MS); |
104 |
l.countDown(); |
105 |
assertEquals(l.getCount(), 1); |
106 |
l.countDown(); |
107 |
assertEquals(l.getCount(), 0); |
108 |
t.join(); |
109 |
} catch (InterruptedException e){ |
110 |
unexpectedException(); |
111 |
} |
112 |
} |
113 |
|
114 |
/** |
115 |
* await throws IE if interrupted before counted down |
116 |
*/ |
117 |
public void testAwait_InterruptedException() { |
118 |
final CountDownLatch l = new CountDownLatch(1); |
119 |
Thread t = new Thread(new Runnable() { |
120 |
public void run() { |
121 |
try { |
122 |
threadAssertTrue(l.getCount() > 0); |
123 |
l.await(); |
124 |
threadShouldThrow(); |
125 |
} catch(InterruptedException success){} |
126 |
} |
127 |
}); |
128 |
t.start(); |
129 |
try { |
130 |
assertEquals(l.getCount(), 1); |
131 |
t.interrupt(); |
132 |
t.join(); |
133 |
} catch (InterruptedException e){ |
134 |
unexpectedException(); |
135 |
} |
136 |
} |
137 |
|
138 |
/** |
139 |
* timed await throws IE if interrupted before counted down |
140 |
*/ |
141 |
public void testTimedAwait_InterruptedException() { |
142 |
final CountDownLatch l = new CountDownLatch(1); |
143 |
Thread t = new Thread(new Runnable() { |
144 |
public void run() { |
145 |
try { |
146 |
threadAssertTrue(l.getCount() > 0); |
147 |
l.await(MEDIUM_DELAY_MS, TimeUnit.MILLISECONDS); |
148 |
threadShouldThrow(); |
149 |
} catch(InterruptedException success){} |
150 |
} |
151 |
}); |
152 |
t.start(); |
153 |
try { |
154 |
Thread.sleep(SHORT_DELAY_MS); |
155 |
assertEquals(l.getCount(), 1); |
156 |
t.interrupt(); |
157 |
t.join(); |
158 |
} catch (InterruptedException e){ |
159 |
unexpectedException(); |
160 |
} |
161 |
} |
162 |
|
163 |
/** |
164 |
* timed await times out if not counted down before timeout |
165 |
*/ |
166 |
public void testAwaitTimeout() { |
167 |
final CountDownLatch l = new CountDownLatch(1); |
168 |
Thread t = new Thread(new Runnable() { |
169 |
public void run() { |
170 |
try { |
171 |
threadAssertTrue(l.getCount() > 0); |
172 |
threadAssertFalse(l.await(SHORT_DELAY_MS, TimeUnit.MILLISECONDS)); |
173 |
threadAssertTrue(l.getCount() > 0); |
174 |
} catch(InterruptedException ie){ |
175 |
threadUnexpectedException(); |
176 |
} |
177 |
} |
178 |
}); |
179 |
t.start(); |
180 |
try { |
181 |
assertEquals(l.getCount(), 1); |
182 |
t.join(); |
183 |
} catch (InterruptedException e){ |
184 |
unexpectedException(); |
185 |
} |
186 |
} |
187 |
|
188 |
} |