1 |
dl |
1.1 |
/* |
2 |
dl |
1.7 |
* Written by Doug Lea with assistance from members of JCP JSR-166 |
3 |
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* Expert Group and released to the public domain, as explained at |
4 |
jsr166 |
1.26 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
5 |
jsr166 |
1.15 |
* Other contributors include Andrew Wright, Jeffrey Hayes, |
6 |
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* Pat Fisher, Mike Judd. |
7 |
dl |
1.1 |
*/ |
8 |
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9 |
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import junit.framework.*; |
10 |
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import java.util.*; |
11 |
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import java.util.concurrent.*; |
12 |
jsr166 |
1.19 |
import static java.util.concurrent.TimeUnit.MILLISECONDS; |
13 |
dl |
1.2 |
import java.io.*; |
14 |
dl |
1.1 |
|
15 |
dl |
1.3 |
public class SemaphoreTest extends JSR166TestCase { |
16 |
dl |
1.1 |
public static void main(String[] args) { |
17 |
jsr166 |
1.24 |
junit.textui.TestRunner.run(suite()); |
18 |
dl |
1.1 |
} |
19 |
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public static Test suite() { |
20 |
jsr166 |
1.20 |
return new TestSuite(SemaphoreTest.class); |
21 |
dl |
1.1 |
} |
22 |
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23 |
dl |
1.4 |
/** |
24 |
dl |
1.6 |
* Subclass to expose protected methods |
25 |
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*/ |
26 |
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static class PublicSemaphore extends Semaphore { |
27 |
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PublicSemaphore(int p, boolean f) { super(p, f); } |
28 |
jsr166 |
1.15 |
public Collection<Thread> getQueuedThreads() { |
29 |
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return super.getQueuedThreads(); |
30 |
dl |
1.6 |
} |
31 |
jsr166 |
1.15 |
public void reducePermits(int p) { |
32 |
dl |
1.6 |
super.reducePermits(p); |
33 |
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} |
34 |
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} |
35 |
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36 |
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/** |
37 |
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* A runnable calling acquire |
38 |
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*/ |
39 |
jsr166 |
1.19 |
class InterruptibleLockRunnable extends CheckedRunnable { |
40 |
dl |
1.6 |
final Semaphore lock; |
41 |
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InterruptibleLockRunnable(Semaphore l) { lock = l; } |
42 |
jsr166 |
1.19 |
public void realRun() { |
43 |
dl |
1.6 |
try { |
44 |
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lock.acquire(); |
45 |
jsr166 |
1.19 |
} |
46 |
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catch (InterruptedException ignored) {} |
47 |
dl |
1.6 |
} |
48 |
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} |
49 |
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50 |
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51 |
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/** |
52 |
jsr166 |
1.21 |
* A runnable calling acquire that expects to be interrupted |
53 |
dl |
1.6 |
*/ |
54 |
jsr166 |
1.19 |
class InterruptedLockRunnable extends CheckedInterruptedRunnable { |
55 |
dl |
1.6 |
final Semaphore lock; |
56 |
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InterruptedLockRunnable(Semaphore l) { lock = l; } |
57 |
jsr166 |
1.19 |
public void realRun() throws InterruptedException { |
58 |
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lock.acquire(); |
59 |
dl |
1.6 |
} |
60 |
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} |
61 |
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62 |
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/** |
63 |
dl |
1.5 |
* Zero, negative, and positive initial values are allowed in constructor |
64 |
dl |
1.4 |
*/ |
65 |
dl |
1.5 |
public void testConstructor() { |
66 |
jsr166 |
1.19 |
for (int permits : new int[] { -1, 0, 1 }) { |
67 |
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for (boolean fair : new boolean[] { false, true }) { |
68 |
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Semaphore s = new Semaphore(permits, fair); |
69 |
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assertEquals(permits, s.availablePermits()); |
70 |
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assertEquals(fair, s.isFair()); |
71 |
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} |
72 |
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} |
73 |
dl |
1.13 |
} |
74 |
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75 |
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/** |
76 |
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* Constructor without fairness argument behaves as nonfair |
77 |
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*/ |
78 |
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public void testConstructor2() { |
79 |
jsr166 |
1.19 |
for (int permits : new int[] { -1, 0, 1 }) { |
80 |
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Semaphore s = new Semaphore(permits); |
81 |
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assertEquals(permits, s.availablePermits()); |
82 |
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assertFalse(s.isFair()); |
83 |
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} |
84 |
dl |
1.1 |
} |
85 |
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|
86 |
dl |
1.4 |
/** |
87 |
dl |
1.9 |
* tryAcquire succeeds when sufficient permits, else fails |
88 |
dl |
1.4 |
*/ |
89 |
dl |
1.1 |
public void testTryAcquireInSameThread() { |
90 |
dl |
1.6 |
Semaphore s = new Semaphore(2, false); |
91 |
dl |
1.1 |
assertEquals(2, s.availablePermits()); |
92 |
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assertTrue(s.tryAcquire()); |
93 |
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assertTrue(s.tryAcquire()); |
94 |
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assertEquals(0, s.availablePermits()); |
95 |
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assertFalse(s.tryAcquire()); |
96 |
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} |
97 |
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98 |
dl |
1.4 |
/** |
99 |
dl |
1.5 |
* Acquire and release of semaphore succeed if initially available |
100 |
dl |
1.4 |
*/ |
101 |
jsr166 |
1.19 |
public void testAcquireReleaseInSameThread() |
102 |
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throws InterruptedException { |
103 |
dl |
1.6 |
Semaphore s = new Semaphore(1, false); |
104 |
jsr166 |
1.19 |
s.acquire(); |
105 |
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s.release(); |
106 |
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s.acquire(); |
107 |
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s.release(); |
108 |
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s.acquire(); |
109 |
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s.release(); |
110 |
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s.acquire(); |
111 |
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s.release(); |
112 |
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s.acquire(); |
113 |
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s.release(); |
114 |
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assertEquals(1, s.availablePermits()); |
115 |
dl |
1.1 |
} |
116 |
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117 |
dl |
1.4 |
/** |
118 |
dl |
1.5 |
* Uninterruptible acquire and release of semaphore succeed if |
119 |
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* initially available |
120 |
dl |
1.4 |
*/ |
121 |
jsr166 |
1.19 |
public void testAcquireUninterruptiblyReleaseInSameThread() |
122 |
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throws InterruptedException { |
123 |
dl |
1.6 |
Semaphore s = new Semaphore(1, false); |
124 |
jsr166 |
1.19 |
s.acquireUninterruptibly(); |
125 |
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s.release(); |
126 |
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s.acquireUninterruptibly(); |
127 |
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s.release(); |
128 |
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s.acquireUninterruptibly(); |
129 |
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s.release(); |
130 |
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s.acquireUninterruptibly(); |
131 |
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s.release(); |
132 |
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s.acquireUninterruptibly(); |
133 |
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s.release(); |
134 |
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assertEquals(1, s.availablePermits()); |
135 |
dl |
1.1 |
} |
136 |
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137 |
dl |
1.5 |
/** |
138 |
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* Timed Acquire and release of semaphore succeed if |
139 |
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* initially available |
140 |
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*/ |
141 |
jsr166 |
1.19 |
public void testTimedAcquireReleaseInSameThread() |
142 |
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throws InterruptedException { |
143 |
dl |
1.6 |
Semaphore s = new Semaphore(1, false); |
144 |
jsr166 |
1.19 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
145 |
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s.release(); |
146 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
147 |
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s.release(); |
148 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
149 |
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s.release(); |
150 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
151 |
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s.release(); |
152 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
153 |
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s.release(); |
154 |
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assertEquals(1, s.availablePermits()); |
155 |
dl |
1.5 |
} |
156 |
dl |
1.1 |
|
157 |
dl |
1.4 |
/** |
158 |
dl |
1.5 |
* A release in one thread enables an acquire in another thread |
159 |
dl |
1.4 |
*/ |
160 |
jsr166 |
1.19 |
public void testAcquireReleaseInDifferentThreads() |
161 |
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throws InterruptedException { |
162 |
dl |
1.6 |
final Semaphore s = new Semaphore(0, false); |
163 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
164 |
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public void realRun() throws InterruptedException { |
165 |
jsr166 |
1.19 |
s.acquire(); |
166 |
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s.release(); |
167 |
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s.release(); |
168 |
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s.acquire(); |
169 |
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}}); |
170 |
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171 |
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t.start(); |
172 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
173 |
jsr166 |
1.19 |
s.release(); |
174 |
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s.release(); |
175 |
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s.acquire(); |
176 |
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s.acquire(); |
177 |
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s.release(); |
178 |
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t.join(); |
179 |
dl |
1.1 |
} |
180 |
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181 |
dl |
1.4 |
/** |
182 |
dl |
1.5 |
* A release in one thread enables an uninterruptible acquire in another thread |
183 |
dl |
1.4 |
*/ |
184 |
jsr166 |
1.19 |
public void testUninterruptibleAcquireReleaseInDifferentThreads() |
185 |
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throws InterruptedException { |
186 |
dl |
1.6 |
final Semaphore s = new Semaphore(0, false); |
187 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
188 |
jsr166 |
1.19 |
public void realRun() throws InterruptedException { |
189 |
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s.acquireUninterruptibly(); |
190 |
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s.release(); |
191 |
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s.release(); |
192 |
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s.acquireUninterruptibly(); |
193 |
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}}); |
194 |
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195 |
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t.start(); |
196 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
197 |
jsr166 |
1.19 |
s.release(); |
198 |
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s.release(); |
199 |
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s.acquireUninterruptibly(); |
200 |
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s.acquireUninterruptibly(); |
201 |
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s.release(); |
202 |
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t.join(); |
203 |
dl |
1.1 |
} |
204 |
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|
205 |
dl |
1.5 |
|
206 |
dl |
1.4 |
/** |
207 |
jsr166 |
1.25 |
* A release in one thread enables a timed acquire in another thread |
208 |
dl |
1.4 |
*/ |
209 |
jsr166 |
1.19 |
public void testTimedAcquireReleaseInDifferentThreads() |
210 |
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throws InterruptedException { |
211 |
dl |
1.6 |
final Semaphore s = new Semaphore(1, false); |
212 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
213 |
jsr166 |
1.19 |
public void realRun() throws InterruptedException { |
214 |
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s.release(); |
215 |
jsr166 |
1.23 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
216 |
jsr166 |
1.19 |
s.release(); |
217 |
jsr166 |
1.23 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
218 |
jsr166 |
1.19 |
}}); |
219 |
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220 |
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t.start(); |
221 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
222 |
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s.release(); |
223 |
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assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
224 |
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s.release(); |
225 |
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s.release(); |
226 |
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t.join(); |
227 |
dl |
1.1 |
} |
228 |
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|
229 |
dl |
1.4 |
/** |
230 |
dl |
1.5 |
* A waiting acquire blocks interruptibly |
231 |
dl |
1.4 |
*/ |
232 |
jsr166 |
1.19 |
public void testAcquire_InterruptedException() |
233 |
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throws InterruptedException { |
234 |
jsr166 |
1.20 |
final Semaphore s = new Semaphore(0, false); |
235 |
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Thread t = new Thread(new CheckedInterruptedRunnable() { |
236 |
|
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public void realRun() throws InterruptedException { |
237 |
jsr166 |
1.19 |
s.acquire(); |
238 |
|
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}}); |
239 |
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|
240 |
jsr166 |
1.20 |
t.start(); |
241 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
242 |
jsr166 |
1.19 |
t.interrupt(); |
243 |
|
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t.join(); |
244 |
dl |
1.1 |
} |
245 |
jsr166 |
1.15 |
|
246 |
dl |
1.4 |
/** |
247 |
jsr166 |
1.25 |
* A waiting timed acquire blocks interruptibly |
248 |
dl |
1.4 |
*/ |
249 |
jsr166 |
1.19 |
public void testTryAcquire_InterruptedException() |
250 |
|
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throws InterruptedException { |
251 |
jsr166 |
1.20 |
final Semaphore s = new Semaphore(0, false); |
252 |
|
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Thread t = new Thread(new CheckedInterruptedRunnable() { |
253 |
|
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public void realRun() throws InterruptedException { |
254 |
jsr166 |
1.19 |
s.tryAcquire(MEDIUM_DELAY_MS, MILLISECONDS); |
255 |
|
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}}); |
256 |
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|
257 |
jsr166 |
1.20 |
t.start(); |
258 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
259 |
jsr166 |
1.19 |
t.interrupt(); |
260 |
|
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t.join(); |
261 |
dl |
1.1 |
} |
262 |
dl |
1.2 |
|
263 |
dl |
1.4 |
/** |
264 |
dl |
1.8 |
* hasQueuedThreads reports whether there are waiting threads |
265 |
|
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*/ |
266 |
jsr166 |
1.19 |
public void testHasQueuedThreads() throws InterruptedException { |
267 |
jsr166 |
1.20 |
final Semaphore lock = new Semaphore(1, false); |
268 |
dl |
1.8 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
269 |
|
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Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
270 |
jsr166 |
1.19 |
assertFalse(lock.hasQueuedThreads()); |
271 |
|
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lock.acquireUninterruptibly(); |
272 |
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t1.start(); |
273 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
274 |
jsr166 |
1.19 |
assertTrue(lock.hasQueuedThreads()); |
275 |
|
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t2.start(); |
276 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
277 |
jsr166 |
1.19 |
assertTrue(lock.hasQueuedThreads()); |
278 |
|
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t1.interrupt(); |
279 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
280 |
jsr166 |
1.19 |
assertTrue(lock.hasQueuedThreads()); |
281 |
|
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lock.release(); |
282 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
283 |
jsr166 |
1.19 |
assertFalse(lock.hasQueuedThreads()); |
284 |
|
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t1.join(); |
285 |
|
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t2.join(); |
286 |
jsr166 |
1.15 |
} |
287 |
dl |
1.8 |
|
288 |
|
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/** |
289 |
dl |
1.6 |
* getQueueLength reports number of waiting threads |
290 |
|
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*/ |
291 |
jsr166 |
1.19 |
public void testGetQueueLength() throws InterruptedException { |
292 |
jsr166 |
1.20 |
final Semaphore lock = new Semaphore(1, false); |
293 |
dl |
1.6 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
294 |
|
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Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
295 |
jsr166 |
1.19 |
assertEquals(0, lock.getQueueLength()); |
296 |
|
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lock.acquireUninterruptibly(); |
297 |
|
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t1.start(); |
298 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
299 |
jsr166 |
1.19 |
assertEquals(1, lock.getQueueLength()); |
300 |
|
|
t2.start(); |
301 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
302 |
jsr166 |
1.19 |
assertEquals(2, lock.getQueueLength()); |
303 |
|
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t1.interrupt(); |
304 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
305 |
jsr166 |
1.19 |
assertEquals(1, lock.getQueueLength()); |
306 |
|
|
lock.release(); |
307 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
308 |
jsr166 |
1.19 |
assertEquals(0, lock.getQueueLength()); |
309 |
|
|
t1.join(); |
310 |
|
|
t2.join(); |
311 |
jsr166 |
1.15 |
} |
312 |
dl |
1.6 |
|
313 |
|
|
/** |
314 |
|
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* getQueuedThreads includes waiting threads |
315 |
|
|
*/ |
316 |
jsr166 |
1.19 |
public void testGetQueuedThreads() throws InterruptedException { |
317 |
jsr166 |
1.20 |
final PublicSemaphore lock = new PublicSemaphore(1, false); |
318 |
dl |
1.6 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
319 |
|
|
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
320 |
jsr166 |
1.19 |
assertTrue(lock.getQueuedThreads().isEmpty()); |
321 |
|
|
lock.acquireUninterruptibly(); |
322 |
|
|
assertTrue(lock.getQueuedThreads().isEmpty()); |
323 |
|
|
t1.start(); |
324 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
325 |
jsr166 |
1.19 |
assertTrue(lock.getQueuedThreads().contains(t1)); |
326 |
|
|
t2.start(); |
327 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
328 |
jsr166 |
1.19 |
assertTrue(lock.getQueuedThreads().contains(t1)); |
329 |
|
|
assertTrue(lock.getQueuedThreads().contains(t2)); |
330 |
|
|
t1.interrupt(); |
331 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
332 |
jsr166 |
1.19 |
assertFalse(lock.getQueuedThreads().contains(t1)); |
333 |
|
|
assertTrue(lock.getQueuedThreads().contains(t2)); |
334 |
|
|
lock.release(); |
335 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
336 |
jsr166 |
1.19 |
assertTrue(lock.getQueuedThreads().isEmpty()); |
337 |
|
|
t1.join(); |
338 |
|
|
t2.join(); |
339 |
jsr166 |
1.15 |
} |
340 |
dl |
1.6 |
|
341 |
dl |
1.11 |
/** |
342 |
|
|
* drainPermits reports and removes given number of permits |
343 |
|
|
*/ |
344 |
|
|
public void testDrainPermits() { |
345 |
|
|
Semaphore s = new Semaphore(0, false); |
346 |
|
|
assertEquals(0, s.availablePermits()); |
347 |
|
|
assertEquals(0, s.drainPermits()); |
348 |
|
|
s.release(10); |
349 |
|
|
assertEquals(10, s.availablePermits()); |
350 |
|
|
assertEquals(10, s.drainPermits()); |
351 |
|
|
assertEquals(0, s.availablePermits()); |
352 |
|
|
assertEquals(0, s.drainPermits()); |
353 |
|
|
} |
354 |
dl |
1.6 |
|
355 |
|
|
/** |
356 |
|
|
* reducePermits reduces number of permits |
357 |
|
|
*/ |
358 |
|
|
public void testReducePermits() { |
359 |
|
|
PublicSemaphore s = new PublicSemaphore(10, false); |
360 |
|
|
assertEquals(10, s.availablePermits()); |
361 |
|
|
s.reducePermits(1); |
362 |
|
|
assertEquals(9, s.availablePermits()); |
363 |
|
|
s.reducePermits(10); |
364 |
|
|
assertEquals(-1, s.availablePermits()); |
365 |
|
|
} |
366 |
|
|
|
367 |
|
|
/** |
368 |
dl |
1.5 |
* a deserialized serialized semaphore has same number of permits |
369 |
dl |
1.4 |
*/ |
370 |
jsr166 |
1.19 |
public void testSerialization() throws Exception { |
371 |
dl |
1.6 |
Semaphore l = new Semaphore(3, false); |
372 |
jsr166 |
1.19 |
l.acquire(); |
373 |
|
|
l.release(); |
374 |
|
|
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
375 |
|
|
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
376 |
|
|
out.writeObject(l); |
377 |
|
|
out.close(); |
378 |
|
|
|
379 |
|
|
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
380 |
|
|
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
381 |
|
|
Semaphore r = (Semaphore) in.readObject(); |
382 |
|
|
assertEquals(3, r.availablePermits()); |
383 |
|
|
assertFalse(r.isFair()); |
384 |
|
|
r.acquire(); |
385 |
|
|
r.release(); |
386 |
dl |
1.6 |
} |
387 |
|
|
|
388 |
|
|
|
389 |
|
|
/** |
390 |
|
|
* Zero, negative, and positive initial values are allowed in constructor |
391 |
|
|
*/ |
392 |
|
|
public void testConstructor_fair() { |
393 |
|
|
Semaphore s0 = new Semaphore(0, true); |
394 |
|
|
assertEquals(0, s0.availablePermits()); |
395 |
|
|
assertTrue(s0.isFair()); |
396 |
|
|
Semaphore s1 = new Semaphore(-1, true); |
397 |
|
|
assertEquals(-1, s1.availablePermits()); |
398 |
|
|
Semaphore s2 = new Semaphore(-1, true); |
399 |
|
|
assertEquals(-1, s2.availablePermits()); |
400 |
|
|
} |
401 |
|
|
|
402 |
|
|
/** |
403 |
dl |
1.9 |
* tryAcquire succeeds when sufficient permits, else fails |
404 |
dl |
1.6 |
*/ |
405 |
|
|
public void testTryAcquireInSameThread_fair() { |
406 |
|
|
Semaphore s = new Semaphore(2, true); |
407 |
|
|
assertEquals(2, s.availablePermits()); |
408 |
|
|
assertTrue(s.tryAcquire()); |
409 |
|
|
assertTrue(s.tryAcquire()); |
410 |
|
|
assertEquals(0, s.availablePermits()); |
411 |
|
|
assertFalse(s.tryAcquire()); |
412 |
|
|
} |
413 |
|
|
|
414 |
|
|
/** |
415 |
dl |
1.9 |
* tryAcquire(n) succeeds when sufficient permits, else fails |
416 |
dl |
1.6 |
*/ |
417 |
|
|
public void testTryAcquireNInSameThread_fair() { |
418 |
|
|
Semaphore s = new Semaphore(2, true); |
419 |
|
|
assertEquals(2, s.availablePermits()); |
420 |
|
|
assertTrue(s.tryAcquire(2)); |
421 |
|
|
assertEquals(0, s.availablePermits()); |
422 |
|
|
assertFalse(s.tryAcquire()); |
423 |
|
|
} |
424 |
|
|
|
425 |
|
|
/** |
426 |
|
|
* Acquire and release of semaphore succeed if initially available |
427 |
|
|
*/ |
428 |
jsr166 |
1.19 |
public void testAcquireReleaseInSameThread_fair() |
429 |
|
|
throws InterruptedException { |
430 |
dl |
1.6 |
Semaphore s = new Semaphore(1, true); |
431 |
jsr166 |
1.19 |
s.acquire(); |
432 |
|
|
s.release(); |
433 |
|
|
s.acquire(); |
434 |
|
|
s.release(); |
435 |
|
|
s.acquire(); |
436 |
|
|
s.release(); |
437 |
|
|
s.acquire(); |
438 |
|
|
s.release(); |
439 |
|
|
s.acquire(); |
440 |
|
|
s.release(); |
441 |
|
|
assertEquals(1, s.availablePermits()); |
442 |
dl |
1.6 |
} |
443 |
|
|
|
444 |
|
|
/** |
445 |
|
|
* Acquire(n) and release(n) of semaphore succeed if initially available |
446 |
|
|
*/ |
447 |
jsr166 |
1.19 |
public void testAcquireReleaseNInSameThread_fair() |
448 |
|
|
throws InterruptedException { |
449 |
dl |
1.6 |
Semaphore s = new Semaphore(1, true); |
450 |
jsr166 |
1.19 |
s.release(1); |
451 |
|
|
s.acquire(1); |
452 |
|
|
s.release(2); |
453 |
|
|
s.acquire(2); |
454 |
|
|
s.release(3); |
455 |
|
|
s.acquire(3); |
456 |
|
|
s.release(4); |
457 |
|
|
s.acquire(4); |
458 |
|
|
s.release(5); |
459 |
|
|
s.acquire(5); |
460 |
|
|
assertEquals(1, s.availablePermits()); |
461 |
dl |
1.6 |
} |
462 |
|
|
|
463 |
|
|
/** |
464 |
|
|
* Acquire(n) and release(n) of semaphore succeed if initially available |
465 |
|
|
*/ |
466 |
|
|
public void testAcquireUninterruptiblyReleaseNInSameThread_fair() { |
467 |
|
|
Semaphore s = new Semaphore(1, true); |
468 |
jsr166 |
1.19 |
s.release(1); |
469 |
|
|
s.acquireUninterruptibly(1); |
470 |
|
|
s.release(2); |
471 |
|
|
s.acquireUninterruptibly(2); |
472 |
|
|
s.release(3); |
473 |
|
|
s.acquireUninterruptibly(3); |
474 |
|
|
s.release(4); |
475 |
|
|
s.acquireUninterruptibly(4); |
476 |
|
|
s.release(5); |
477 |
|
|
s.acquireUninterruptibly(5); |
478 |
|
|
assertEquals(1, s.availablePermits()); |
479 |
dl |
1.6 |
} |
480 |
|
|
|
481 |
|
|
/** |
482 |
|
|
* release(n) in one thread enables timed acquire(n) in another thread |
483 |
|
|
*/ |
484 |
jsr166 |
1.19 |
public void testTimedAcquireReleaseNInSameThread_fair() |
485 |
|
|
throws InterruptedException { |
486 |
dl |
1.6 |
Semaphore s = new Semaphore(1, true); |
487 |
jsr166 |
1.19 |
s.release(1); |
488 |
|
|
assertTrue(s.tryAcquire(1, SHORT_DELAY_MS, MILLISECONDS)); |
489 |
|
|
s.release(2); |
490 |
|
|
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, MILLISECONDS)); |
491 |
|
|
s.release(3); |
492 |
|
|
assertTrue(s.tryAcquire(3, SHORT_DELAY_MS, MILLISECONDS)); |
493 |
|
|
s.release(4); |
494 |
|
|
assertTrue(s.tryAcquire(4, SHORT_DELAY_MS, MILLISECONDS)); |
495 |
|
|
s.release(5); |
496 |
|
|
assertTrue(s.tryAcquire(5, SHORT_DELAY_MS, MILLISECONDS)); |
497 |
|
|
assertEquals(1, s.availablePermits()); |
498 |
dl |
1.6 |
} |
499 |
|
|
|
500 |
|
|
/** |
501 |
|
|
* release in one thread enables timed acquire in another thread |
502 |
|
|
*/ |
503 |
jsr166 |
1.19 |
public void testTimedAcquireReleaseInSameThread_fair() |
504 |
|
|
throws InterruptedException { |
505 |
dl |
1.6 |
Semaphore s = new Semaphore(1, true); |
506 |
jsr166 |
1.19 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
507 |
|
|
s.release(); |
508 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
509 |
|
|
s.release(); |
510 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
511 |
|
|
s.release(); |
512 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
513 |
|
|
s.release(); |
514 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
515 |
|
|
s.release(); |
516 |
|
|
assertEquals(1, s.availablePermits()); |
517 |
dl |
1.6 |
} |
518 |
|
|
|
519 |
|
|
/** |
520 |
|
|
* A release in one thread enables an acquire in another thread |
521 |
|
|
*/ |
522 |
jsr166 |
1.19 |
public void testAcquireReleaseInDifferentThreads_fair() |
523 |
|
|
throws InterruptedException { |
524 |
dl |
1.6 |
final Semaphore s = new Semaphore(0, true); |
525 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
526 |
|
|
public void realRun() throws InterruptedException { |
527 |
jsr166 |
1.19 |
s.acquire(); |
528 |
|
|
s.acquire(); |
529 |
|
|
s.acquire(); |
530 |
|
|
s.acquire(); |
531 |
|
|
}}); |
532 |
|
|
|
533 |
|
|
t.start(); |
534 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
535 |
jsr166 |
1.19 |
s.release(); |
536 |
|
|
s.release(); |
537 |
|
|
s.release(); |
538 |
|
|
s.release(); |
539 |
|
|
s.release(); |
540 |
|
|
s.release(); |
541 |
|
|
t.join(); |
542 |
|
|
assertEquals(2, s.availablePermits()); |
543 |
dl |
1.6 |
} |
544 |
|
|
|
545 |
|
|
/** |
546 |
|
|
* release(n) in one thread enables acquire(n) in another thread |
547 |
|
|
*/ |
548 |
jsr166 |
1.19 |
public void testAcquireReleaseNInDifferentThreads_fair() |
549 |
|
|
throws InterruptedException { |
550 |
dl |
1.6 |
final Semaphore s = new Semaphore(0, true); |
551 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
552 |
|
|
public void realRun() throws InterruptedException { |
553 |
jsr166 |
1.19 |
s.acquire(); |
554 |
|
|
s.release(2); |
555 |
|
|
s.acquire(); |
556 |
|
|
}}); |
557 |
|
|
|
558 |
|
|
t.start(); |
559 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
560 |
jsr166 |
1.19 |
s.release(2); |
561 |
|
|
s.acquire(2); |
562 |
|
|
s.release(1); |
563 |
|
|
t.join(); |
564 |
dl |
1.6 |
} |
565 |
|
|
|
566 |
dl |
1.12 |
/** |
567 |
|
|
* release(n) in one thread enables acquire(n) in another thread |
568 |
|
|
*/ |
569 |
jsr166 |
1.19 |
public void testAcquireReleaseNInDifferentThreads_fair2() |
570 |
|
|
throws InterruptedException { |
571 |
dl |
1.12 |
final Semaphore s = new Semaphore(0, true); |
572 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
573 |
|
|
public void realRun() throws InterruptedException { |
574 |
jsr166 |
1.19 |
s.acquire(2); |
575 |
|
|
s.acquire(2); |
576 |
|
|
s.release(4); |
577 |
|
|
}}); |
578 |
|
|
|
579 |
|
|
t.start(); |
580 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
581 |
jsr166 |
1.19 |
s.release(6); |
582 |
|
|
s.acquire(2); |
583 |
|
|
s.acquire(2); |
584 |
|
|
s.release(2); |
585 |
|
|
t.join(); |
586 |
dl |
1.12 |
} |
587 |
|
|
|
588 |
|
|
|
589 |
dl |
1.6 |
/** |
590 |
|
|
* release in one thread enables timed acquire in another thread |
591 |
|
|
*/ |
592 |
jsr166 |
1.19 |
public void testTimedAcquireReleaseInDifferentThreads_fair() |
593 |
|
|
throws InterruptedException { |
594 |
dl |
1.6 |
final Semaphore s = new Semaphore(1, true); |
595 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
596 |
|
|
public void realRun() throws InterruptedException { |
597 |
jsr166 |
1.23 |
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
598 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
599 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
600 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
601 |
|
|
assertTrue(s.tryAcquire(SHORT_DELAY_MS, MILLISECONDS)); |
602 |
jsr166 |
1.19 |
}}); |
603 |
|
|
|
604 |
jsr166 |
1.20 |
t.start(); |
605 |
jsr166 |
1.19 |
s.release(); |
606 |
|
|
s.release(); |
607 |
|
|
s.release(); |
608 |
|
|
s.release(); |
609 |
|
|
s.release(); |
610 |
|
|
t.join(); |
611 |
dl |
1.6 |
} |
612 |
|
|
|
613 |
|
|
/** |
614 |
|
|
* release(n) in one thread enables timed acquire(n) in another thread |
615 |
|
|
*/ |
616 |
jsr166 |
1.19 |
public void testTimedAcquireReleaseNInDifferentThreads_fair() |
617 |
|
|
throws InterruptedException { |
618 |
dl |
1.6 |
final Semaphore s = new Semaphore(2, true); |
619 |
jsr166 |
1.20 |
Thread t = new Thread(new CheckedRunnable() { |
620 |
|
|
public void realRun() throws InterruptedException { |
621 |
jsr166 |
1.22 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, MILLISECONDS)); |
622 |
jsr166 |
1.19 |
s.release(2); |
623 |
jsr166 |
1.22 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, MILLISECONDS)); |
624 |
jsr166 |
1.19 |
s.release(2); |
625 |
|
|
}}); |
626 |
|
|
|
627 |
jsr166 |
1.20 |
t.start(); |
628 |
jsr166 |
1.19 |
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, MILLISECONDS)); |
629 |
|
|
s.release(2); |
630 |
|
|
assertTrue(s.tryAcquire(2, SHORT_DELAY_MS, MILLISECONDS)); |
631 |
|
|
s.release(2); |
632 |
|
|
t.join(); |
633 |
dl |
1.6 |
} |
634 |
|
|
|
635 |
|
|
/** |
636 |
|
|
* A waiting acquire blocks interruptibly |
637 |
|
|
*/ |
638 |
jsr166 |
1.19 |
public void testAcquire_InterruptedException_fair() |
639 |
|
|
throws InterruptedException { |
640 |
jsr166 |
1.20 |
final Semaphore s = new Semaphore(0, true); |
641 |
|
|
Thread t = new Thread(new CheckedInterruptedRunnable() { |
642 |
|
|
public void realRun() throws InterruptedException { |
643 |
jsr166 |
1.19 |
s.acquire(); |
644 |
|
|
}}); |
645 |
|
|
|
646 |
jsr166 |
1.20 |
t.start(); |
647 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
648 |
jsr166 |
1.19 |
t.interrupt(); |
649 |
|
|
t.join(); |
650 |
dl |
1.6 |
} |
651 |
|
|
|
652 |
|
|
/** |
653 |
|
|
* A waiting acquire(n) blocks interruptibly |
654 |
|
|
*/ |
655 |
jsr166 |
1.19 |
public void testAcquireN_InterruptedException_fair() |
656 |
|
|
throws InterruptedException { |
657 |
jsr166 |
1.20 |
final Semaphore s = new Semaphore(2, true); |
658 |
|
|
Thread t = new Thread(new CheckedInterruptedRunnable() { |
659 |
|
|
public void realRun() throws InterruptedException { |
660 |
jsr166 |
1.19 |
s.acquire(3); |
661 |
|
|
}}); |
662 |
|
|
|
663 |
jsr166 |
1.20 |
t.start(); |
664 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
665 |
jsr166 |
1.19 |
t.interrupt(); |
666 |
|
|
t.join(); |
667 |
dl |
1.6 |
} |
668 |
jsr166 |
1.15 |
|
669 |
dl |
1.6 |
/** |
670 |
jsr166 |
1.25 |
* A waiting tryAcquire blocks interruptibly |
671 |
dl |
1.6 |
*/ |
672 |
jsr166 |
1.19 |
public void testTryAcquire_InterruptedException_fair() |
673 |
|
|
throws InterruptedException { |
674 |
jsr166 |
1.20 |
final Semaphore s = new Semaphore(0, true); |
675 |
|
|
Thread t = new Thread(new CheckedInterruptedRunnable() { |
676 |
|
|
public void realRun() throws InterruptedException { |
677 |
jsr166 |
1.19 |
s.tryAcquire(MEDIUM_DELAY_MS, MILLISECONDS); |
678 |
|
|
}}); |
679 |
|
|
|
680 |
jsr166 |
1.20 |
t.start(); |
681 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
682 |
jsr166 |
1.19 |
t.interrupt(); |
683 |
|
|
t.join(); |
684 |
dl |
1.6 |
} |
685 |
|
|
|
686 |
|
|
/** |
687 |
jsr166 |
1.25 |
* A waiting tryAcquire(n) blocks interruptibly |
688 |
dl |
1.6 |
*/ |
689 |
jsr166 |
1.19 |
public void testTryAcquireN_InterruptedException_fair() |
690 |
|
|
throws InterruptedException { |
691 |
jsr166 |
1.20 |
final Semaphore s = new Semaphore(1, true); |
692 |
|
|
Thread t = new Thread(new CheckedInterruptedRunnable() { |
693 |
|
|
public void realRun() throws InterruptedException { |
694 |
jsr166 |
1.19 |
s.tryAcquire(4, MEDIUM_DELAY_MS, MILLISECONDS); |
695 |
|
|
}}); |
696 |
|
|
|
697 |
jsr166 |
1.20 |
t.start(); |
698 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
699 |
jsr166 |
1.19 |
t.interrupt(); |
700 |
|
|
t.join(); |
701 |
dl |
1.6 |
} |
702 |
|
|
|
703 |
|
|
/** |
704 |
|
|
* getQueueLength reports number of waiting threads |
705 |
|
|
*/ |
706 |
jsr166 |
1.19 |
public void testGetQueueLength_fair() throws InterruptedException { |
707 |
jsr166 |
1.20 |
final Semaphore lock = new Semaphore(1, true); |
708 |
dl |
1.6 |
Thread t1 = new Thread(new InterruptedLockRunnable(lock)); |
709 |
|
|
Thread t2 = new Thread(new InterruptibleLockRunnable(lock)); |
710 |
jsr166 |
1.19 |
assertEquals(0, lock.getQueueLength()); |
711 |
|
|
lock.acquireUninterruptibly(); |
712 |
|
|
t1.start(); |
713 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
714 |
jsr166 |
1.19 |
assertEquals(1, lock.getQueueLength()); |
715 |
|
|
t2.start(); |
716 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
717 |
jsr166 |
1.19 |
assertEquals(2, lock.getQueueLength()); |
718 |
|
|
t1.interrupt(); |
719 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
720 |
jsr166 |
1.19 |
assertEquals(1, lock.getQueueLength()); |
721 |
|
|
lock.release(); |
722 |
dl |
1.27 |
delay(SHORT_DELAY_MS); |
723 |
jsr166 |
1.19 |
assertEquals(0, lock.getQueueLength()); |
724 |
|
|
t1.join(); |
725 |
|
|
t2.join(); |
726 |
jsr166 |
1.15 |
} |
727 |
dl |
1.6 |
|
728 |
|
|
|
729 |
|
|
/** |
730 |
|
|
* a deserialized serialized semaphore has same number of permits |
731 |
|
|
*/ |
732 |
jsr166 |
1.19 |
public void testSerialization_fair() throws Exception { |
733 |
dl |
1.6 |
Semaphore l = new Semaphore(3, true); |
734 |
|
|
|
735 |
jsr166 |
1.19 |
l.acquire(); |
736 |
|
|
l.release(); |
737 |
|
|
ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
738 |
|
|
ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
739 |
|
|
out.writeObject(l); |
740 |
|
|
out.close(); |
741 |
|
|
|
742 |
|
|
ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
743 |
|
|
ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
744 |
|
|
Semaphore r = (Semaphore) in.readObject(); |
745 |
|
|
assertEquals(3, r.availablePermits()); |
746 |
|
|
assertTrue(r.isFair()); |
747 |
|
|
r.acquire(); |
748 |
|
|
r.release(); |
749 |
dl |
1.2 |
} |
750 |
dl |
1.6 |
|
751 |
dl |
1.14 |
/** |
752 |
|
|
* toString indicates current number of permits |
753 |
|
|
*/ |
754 |
|
|
public void testToString() { |
755 |
|
|
Semaphore s = new Semaphore(0); |
756 |
|
|
String us = s.toString(); |
757 |
|
|
assertTrue(us.indexOf("Permits = 0") >= 0); |
758 |
|
|
s.release(); |
759 |
|
|
String s1 = s.toString(); |
760 |
|
|
assertTrue(s1.indexOf("Permits = 1") >= 0); |
761 |
|
|
s.release(); |
762 |
|
|
String s2 = s.toString(); |
763 |
|
|
assertTrue(s2.indexOf("Permits = 2") >= 0); |
764 |
|
|
} |
765 |
dl |
1.2 |
|
766 |
dl |
1.1 |
} |