1 |
/* |
2 |
* Written by Doug Lea with assistance from members of JCP JSR-166 |
3 |
* Expert Group and released to the public domain, as explained at |
4 |
* http://creativecommons.org/publicdomain/zero/1.0/ |
5 |
* Other contributors include Andrew Wright, Jeffrey Hayes, |
6 |
* Pat Fisher, Mike Judd. |
7 |
*/ |
8 |
|
9 |
import junit.framework.*; |
10 |
import java.util.*; |
11 |
import java.util.concurrent.*; |
12 |
import static java.util.concurrent.TimeUnit.MILLISECONDS; |
13 |
|
14 |
public class ExchangerTest extends JSR166TestCase { |
15 |
|
16 |
public static void main(String[] args) { |
17 |
junit.textui.TestRunner.run(suite()); |
18 |
} |
19 |
public static Test suite() { |
20 |
return new TestSuite(ExchangerTest.class); |
21 |
} |
22 |
|
23 |
/** |
24 |
* exchange exchanges objects across two threads |
25 |
*/ |
26 |
public void testExchange() { |
27 |
final Exchanger e = new Exchanger(); |
28 |
Thread t1 = newStartedThread(new CheckedRunnable() { |
29 |
public void realRun() throws InterruptedException { |
30 |
assertSame(one, e.exchange(two)); |
31 |
assertSame(two, e.exchange(one)); |
32 |
}}); |
33 |
Thread t2 = newStartedThread(new CheckedRunnable() { |
34 |
public void realRun() throws InterruptedException { |
35 |
assertSame(two, e.exchange(one)); |
36 |
assertSame(one, e.exchange(two)); |
37 |
}}); |
38 |
|
39 |
awaitTermination(t1); |
40 |
awaitTermination(t2); |
41 |
} |
42 |
|
43 |
/** |
44 |
* timed exchange exchanges objects across two threads |
45 |
*/ |
46 |
public void testTimedExchange() { |
47 |
final Exchanger e = new Exchanger(); |
48 |
Thread t1 = newStartedThread(new CheckedRunnable() { |
49 |
public void realRun() throws Exception { |
50 |
assertSame(one, e.exchange(two, LONG_DELAY_MS, MILLISECONDS)); |
51 |
assertSame(two, e.exchange(one, LONG_DELAY_MS, MILLISECONDS)); |
52 |
}}); |
53 |
Thread t2 = newStartedThread(new CheckedRunnable() { |
54 |
public void realRun() throws Exception { |
55 |
assertSame(two, e.exchange(one, LONG_DELAY_MS, MILLISECONDS)); |
56 |
assertSame(one, e.exchange(two, LONG_DELAY_MS, MILLISECONDS)); |
57 |
}}); |
58 |
|
59 |
awaitTermination(t1); |
60 |
awaitTermination(t2); |
61 |
} |
62 |
|
63 |
/** |
64 |
* interrupt during wait for exchange throws IE |
65 |
*/ |
66 |
public void testExchange_InterruptedException() { |
67 |
final Exchanger e = new Exchanger(); |
68 |
final CountDownLatch threadStarted = new CountDownLatch(1); |
69 |
Thread t = newStartedThread(new CheckedInterruptedRunnable() { |
70 |
public void realRun() throws InterruptedException { |
71 |
threadStarted.countDown(); |
72 |
e.exchange(one); |
73 |
}}); |
74 |
|
75 |
await(threadStarted); |
76 |
t.interrupt(); |
77 |
awaitTermination(t); |
78 |
} |
79 |
|
80 |
/** |
81 |
* interrupt during wait for timed exchange throws IE |
82 |
*/ |
83 |
public void testTimedExchange_InterruptedException() { |
84 |
final Exchanger e = new Exchanger(); |
85 |
final CountDownLatch threadStarted = new CountDownLatch(1); |
86 |
Thread t = newStartedThread(new CheckedInterruptedRunnable() { |
87 |
public void realRun() throws Exception { |
88 |
threadStarted.countDown(); |
89 |
e.exchange(null, LONG_DELAY_MS, MILLISECONDS); |
90 |
}}); |
91 |
|
92 |
await(threadStarted); |
93 |
t.interrupt(); |
94 |
awaitTermination(t); |
95 |
} |
96 |
|
97 |
/** |
98 |
* timeout during wait for timed exchange throws TimeoutException |
99 |
*/ |
100 |
public void testExchange_TimeoutException() { |
101 |
final Exchanger e = new Exchanger(); |
102 |
Thread t = newStartedThread(new CheckedRunnable() { |
103 |
public void realRun() throws Exception { |
104 |
long timeoutMillis = SHORT_DELAY_MS; |
105 |
long startTime = System.nanoTime(); |
106 |
try { |
107 |
e.exchange(null, timeoutMillis, MILLISECONDS); |
108 |
shouldThrow(); |
109 |
} catch (TimeoutException success) { |
110 |
assertTrue(millisElapsedSince(startTime) >= timeoutMillis); |
111 |
} |
112 |
}}); |
113 |
|
114 |
awaitTermination(t); |
115 |
} |
116 |
|
117 |
/** |
118 |
* If one exchanging thread is interrupted, another succeeds. |
119 |
*/ |
120 |
public void testReplacementAfterExchange() { |
121 |
final Exchanger e = new Exchanger(); |
122 |
final CountDownLatch exchanged = new CountDownLatch(2); |
123 |
final CountDownLatch interrupted = new CountDownLatch(1); |
124 |
Thread t1 = newStartedThread(new CheckedInterruptedRunnable() { |
125 |
public void realRun() throws InterruptedException { |
126 |
assertSame(two, e.exchange(one)); |
127 |
exchanged.countDown(); |
128 |
e.exchange(two); |
129 |
}}); |
130 |
Thread t2 = newStartedThread(new CheckedRunnable() { |
131 |
public void realRun() throws InterruptedException { |
132 |
assertSame(one, e.exchange(two)); |
133 |
exchanged.countDown(); |
134 |
interrupted.await(); |
135 |
assertSame(three, e.exchange(one)); |
136 |
}}); |
137 |
Thread t3 = newStartedThread(new CheckedRunnable() { |
138 |
public void realRun() throws InterruptedException { |
139 |
interrupted.await(); |
140 |
assertSame(one, e.exchange(three)); |
141 |
}}); |
142 |
|
143 |
await(exchanged); |
144 |
t1.interrupt(); |
145 |
awaitTermination(t1); |
146 |
interrupted.countDown(); |
147 |
awaitTermination(t2); |
148 |
awaitTermination(t3); |
149 |
} |
150 |
|
151 |
} |