test/tck/CountDownLatchTest.java

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 * Other contributors include Andrew Wright, Jeffrey Hayes,
 * Pat Fisher, Mike Judd.
 */

import junit.framework.*;
import java.util.*;
import java.util.concurrent.*;
import static java.util.concurrent.TimeUnit.MILLISECONDS;

public class CountDownLatchTest extends JSR166TestCase {
    public static void main(String[] args) {
        junit.textui.TestRunner.run(suite());
    }
    public static Test suite() {
        return new TestSuite(CountDownLatchTest.class);
    }

    /**
     * negative constructor argument throws IAE
     */
    public void testConstructor() {
        try {
            new CountDownLatch(-1);
            shouldThrow();
        } catch (IllegalArgumentException success) {}
    }

    /**
     * getCount returns initial count and decreases after countDown
     */
    public void testGetCount() {
        final CountDownLatch l = new CountDownLatch(2);
        assertEquals(2, l.getCount());
        l.countDown();
        assertEquals(1, l.getCount());
    }

    /**
     * countDown decrements count when positive and has no effect when zero
     */
    public void testCountDown() {
        final CountDownLatch l = new CountDownLatch(1);
        assertEquals(1, l.getCount());
        l.countDown();
        assertEquals(0, l.getCount());
        l.countDown();
        assertEquals(0, l.getCount());
    }

    /**
     * await returns after countDown to zero, but not before
     */
    public void testAwait() throws InterruptedException {
        final CountDownLatch l = new CountDownLatch(2);

        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                assertTrue(l.getCount() > 0);
                l.await();
                assertEquals(0, l.getCount());
            }});

        t.start();
        assertEquals(l.getCount(), 2);
        delay(SHORT_DELAY_MS);
        l.countDown();
        assertEquals(l.getCount(), 1);
        l.countDown();
        assertEquals(l.getCount(), 0);
        t.join();
    }

    /**
     * timed await returns after countDown to zero
     */
    public void testTimedAwait() throws InterruptedException {
        final CountDownLatch l = new CountDownLatch(2);

        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                assertTrue(l.getCount() > 0);
                assertTrue(l.await(SMALL_DELAY_MS, MILLISECONDS));
            }});

        t.start();
        assertEquals(l.getCount(), 2);
        delay(SHORT_DELAY_MS);
        l.countDown();
        assertEquals(l.getCount(), 1);
        l.countDown();
        assertEquals(l.getCount(), 0);
        t.join();
    }

    /**
     * await throws IE if interrupted before counted down
     */
    public void testAwait_InterruptedException() throws InterruptedException {
        final CountDownLatch l = new CountDownLatch(1);
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                assertTrue(l.getCount() > 0);
                l.await();
            }});

        t.start();
        assertEquals(l.getCount(), 1);
        t.interrupt();
        t.join();
    }

    /**
     * timed await throws IE if interrupted before counted down
     */
    public void testTimedAwait_InterruptedException() throws InterruptedException {
        final CountDownLatch l = new CountDownLatch(1);
        Thread t = new Thread(new CheckedInterruptedRunnable() {
            public void realRun() throws InterruptedException {
                assertTrue(l.getCount() > 0);
                l.await(MEDIUM_DELAY_MS, MILLISECONDS);
            }});

        t.start();
        delay(SHORT_DELAY_MS);
        assertEquals(l.getCount(), 1);
        t.interrupt();
        t.join();
    }

    /**
     * timed await times out if not counted down before timeout
     */
    public void testAwaitTimeout() throws InterruptedException {
        final CountDownLatch l = new CountDownLatch(1);
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() throws InterruptedException {
                assertTrue(l.getCount() > 0);
                assertFalse(l.await(SHORT_DELAY_MS, MILLISECONDS));
                assertTrue(l.getCount() > 0);
            }});

        t.start();
        assertEquals(l.getCount(), 1);
        t.join();
    }

    /**
     * toString indicates current count
     */
    public void testToString() {
        CountDownLatch s = new CountDownLatch(2);
        assertTrue(s.toString().contains("Count = 2"));
        s.countDown();
        assertTrue(s.toString().contains("Count = 1"));
        s.countDown();
        assertTrue(s.toString().contains("Count = 0"));
    }

}
Revision:	1.19
Committed:	Fri May 27 19:40:19 2011 UTC (12 years, 11 months ago) by jsr166
Branch:	MAIN
Changes since 1.18:	+0 -1 lines
Log Message:	whitespace
#	User	Rev	Content
1	dl	1.1	/*
2	dl	1.6	* 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	jsr166	1.16	* http://creativecommons.org/publicdomain/zero/1.0/
5	jsr166	1.8	* Other contributors include Andrew Wright, Jeffrey Hayes,
6			* Pat Fisher, Mike Judd.
7	dl	1.1	*/
8
9			import junit.framework.*;
10			import java.util.*;
11			import java.util.concurrent.*;
12	jsr166	1.12	import static java.util.concurrent.TimeUnit.MILLISECONDS;
13	dl	1.1
14	dl	1.2	public class CountDownLatchTest extends JSR166TestCase {
15	dl	1.1	public static void main(String[] args) {
16	jsr166	1.14	junit.textui.TestRunner.run(suite());
17	dl	1.1	}
18			public static Test suite() {
19	jsr166	1.11	return new TestSuite(CountDownLatchTest.class);
20	dl	1.1	}
21
22	dl	1.3	/**
23	dl	1.4	* negative constructor argument throws IAE
24	dl	1.3	*/
25			public void testConstructor() {
26	dl	1.2	try {
27			new CountDownLatch(-1);
28	dl	1.3	shouldThrow();
29	jsr166	1.10	} catch (IllegalArgumentException success) {}
30	dl	1.2	}
31	dl	1.1
32	dl	1.3	/**
33	dl	1.4	* getCount returns initial count and decreases after countDown
34	dl	1.3	*/
35			public void testGetCount() {
36	jsr166	1.11	final CountDownLatch l = new CountDownLatch(2);
37			assertEquals(2, l.getCount());
38			l.countDown();
39			assertEquals(1, l.getCount());
40	dl	1.1	}
41
42	dl	1.3	/**
43	dl	1.5	* countDown decrements count when positive and has no effect when zero
44	dl	1.4	*/
45	dl	1.5	public void testCountDown() {
46	jsr166	1.11	final CountDownLatch l = new CountDownLatch(1);
47			assertEquals(1, l.getCount());
48			l.countDown();
49			assertEquals(0, l.getCount());
50			l.countDown();
51			assertEquals(0, l.getCount());
52	dl	1.4	}
53
54			/**
55			* await returns after countDown to zero, but not before
56	dl	1.3	*/
57	jsr166	1.13	public void testAwait() throws InterruptedException {
58	jsr166	1.11	final CountDownLatch l = new CountDownLatch(2);
59	dl	1.1
60	jsr166	1.13	Thread t = new Thread(new CheckedRunnable() {
61			public void realRun() throws InterruptedException {
62	jsr166	1.15	assertTrue(l.getCount() > 0);
63	jsr166	1.13	l.await();
64	jsr166	1.15	assertEquals(0, l.getCount());
65	jsr166	1.13	}});
66
67	jsr166	1.11	t.start();
68	jsr166	1.13	assertEquals(l.getCount(), 2);
69	dl	1.17	delay(SHORT_DELAY_MS);
70	jsr166	1.13	l.countDown();
71			assertEquals(l.getCount(), 1);
72			l.countDown();
73			assertEquals(l.getCount(), 0);
74			t.join();
75	dl	1.1	}
76	jsr166	1.8
77	dl	1.3	/**
78	dl	1.4	* timed await returns after countDown to zero
79	dl	1.3	*/
80	jsr166	1.13	public void testTimedAwait() throws InterruptedException {
81	jsr166	1.11	final CountDownLatch l = new CountDownLatch(2);
82	dl	1.1
83	jsr166	1.13	Thread t = new Thread(new CheckedRunnable() {
84			public void realRun() throws InterruptedException {
85	jsr166	1.15	assertTrue(l.getCount() > 0);
86			assertTrue(l.await(SMALL_DELAY_MS, MILLISECONDS));
87	jsr166	1.13	}});
88
89	jsr166	1.11	t.start();
90	jsr166	1.13	assertEquals(l.getCount(), 2);
91	dl	1.17	delay(SHORT_DELAY_MS);
92	jsr166	1.13	l.countDown();
93			assertEquals(l.getCount(), 1);
94			l.countDown();
95			assertEquals(l.getCount(), 0);
96			t.join();
97	dl	1.1	}
98	jsr166	1.8
99	dl	1.3	/**
100	dl	1.5	* await throws IE if interrupted before counted down
101	dl	1.3	*/
102	jsr166	1.13	public void testAwait_InterruptedException() throws InterruptedException {
103	dl	1.1	final CountDownLatch l = new CountDownLatch(1);
104	jsr166	1.13	Thread t = new Thread(new CheckedInterruptedRunnable() {
105			public void realRun() throws InterruptedException {
106	jsr166	1.15	assertTrue(l.getCount() > 0);
107	jsr166	1.13	l.await();
108			}});
109
110	jsr166	1.11	t.start();
111	jsr166	1.13	assertEquals(l.getCount(), 1);
112			t.interrupt();
113			t.join();
114	dl	1.1	}
115
116	dl	1.3	/**
117	dl	1.5	* timed await throws IE if interrupted before counted down
118	dl	1.3	*/
119	jsr166	1.13	public void testTimedAwait_InterruptedException() throws InterruptedException {
120	dl	1.1	final CountDownLatch l = new CountDownLatch(1);
121	jsr166	1.13	Thread t = new Thread(new CheckedInterruptedRunnable() {
122			public void realRun() throws InterruptedException {
123	jsr166	1.15	assertTrue(l.getCount() > 0);
124	jsr166	1.13	l.await(MEDIUM_DELAY_MS, MILLISECONDS);
125			}});
126
127	dl	1.1	t.start();
128	dl	1.17	delay(SHORT_DELAY_MS);
129	jsr166	1.13	assertEquals(l.getCount(), 1);
130			t.interrupt();
131			t.join();
132	dl	1.1	}
133
134	dl	1.3	/**
135	dl	1.4	* timed await times out if not counted down before timeout
136	dl	1.3	*/
137	jsr166	1.13	public void testAwaitTimeout() throws InterruptedException {
138	dl	1.1	final CountDownLatch l = new CountDownLatch(1);
139	jsr166	1.13	Thread t = new Thread(new CheckedRunnable() {
140			public void realRun() throws InterruptedException {
141	jsr166	1.15	assertTrue(l.getCount() > 0);
142			assertFalse(l.await(SHORT_DELAY_MS, MILLISECONDS));
143			assertTrue(l.getCount() > 0);
144	jsr166	1.13	}});
145
146	dl	1.1	t.start();
147	jsr166	1.13	assertEquals(l.getCount(), 1);
148			t.join();
149	dl	1.1	}
150
151	dl	1.7	/**
152			* toString indicates current count
153			*/
154			public void testToString() {
155			CountDownLatch s = new CountDownLatch(2);
156	jsr166	1.18	assertTrue(s.toString().contains("Count = 2"));
157	dl	1.7	s.countDown();
158	jsr166	1.18	assertTrue(s.toString().contains("Count = 1"));
159	dl	1.7	s.countDown();
160	jsr166	1.18	assertTrue(s.toString().contains("Count = 0"));
161	dl	1.7	}
162
163	dl	1.1	}