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
#	Content
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 CountDownLatchTest extends JSR166TestCase {
15	public static void main(String[] args) {
16	junit.textui.TestRunner.run(suite());
17	}
18	public static Test suite() {
19	return new TestSuite(CountDownLatchTest.class);
20	}
21
22	/**
23	* negative constructor argument throws IAE
24	*/
25	public void testConstructor() {
26	try {
27	new CountDownLatch(-1);
28	shouldThrow();
29	} catch (IllegalArgumentException success) {}
30	}
31
32	/**
33	* getCount returns initial count and decreases after countDown
34	*/
35	public void testGetCount() {
36	final CountDownLatch l = new CountDownLatch(2);
37	assertEquals(2, l.getCount());
38	l.countDown();
39	assertEquals(1, l.getCount());
40	}
41
42	/**
43	* countDown decrements count when positive and has no effect when zero
44	*/
45	public void testCountDown() {
46	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	}
53
54	/**
55	* await returns after countDown to zero, but not before
56	*/
57	public void testAwait() throws InterruptedException {
58	final CountDownLatch l = new CountDownLatch(2);
59
60	Thread t = new Thread(new CheckedRunnable() {
61	public void realRun() throws InterruptedException {
62	assertTrue(l.getCount() > 0);
63	l.await();
64	assertEquals(0, l.getCount());
65	}});
66
67	t.start();
68	assertEquals(l.getCount(), 2);
69	delay(SHORT_DELAY_MS);
70	l.countDown();
71	assertEquals(l.getCount(), 1);
72	l.countDown();
73	assertEquals(l.getCount(), 0);
74	t.join();
75	}
76
77	/**
78	* timed await returns after countDown to zero
79	*/
80	public void testTimedAwait() throws InterruptedException {
81	final CountDownLatch l = new CountDownLatch(2);
82
83	Thread t = new Thread(new CheckedRunnable() {
84	public void realRun() throws InterruptedException {
85	assertTrue(l.getCount() > 0);
86	assertTrue(l.await(SMALL_DELAY_MS, MILLISECONDS));
87	}});
88
89	t.start();
90	assertEquals(l.getCount(), 2);
91	delay(SHORT_DELAY_MS);
92	l.countDown();
93	assertEquals(l.getCount(), 1);
94	l.countDown();
95	assertEquals(l.getCount(), 0);
96	t.join();
97	}
98
99	/**
100	* await throws IE if interrupted before counted down
101	*/
102	public void testAwait_InterruptedException() throws InterruptedException {
103	final CountDownLatch l = new CountDownLatch(1);
104	Thread t = new Thread(new CheckedInterruptedRunnable() {
105	public void realRun() throws InterruptedException {
106	assertTrue(l.getCount() > 0);
107	l.await();
108	}});
109
110	t.start();
111	assertEquals(l.getCount(), 1);
112	t.interrupt();
113	t.join();
114	}
115
116	/**
117	* timed await throws IE if interrupted before counted down
118	*/
119	public void testTimedAwait_InterruptedException() throws InterruptedException {
120	final CountDownLatch l = new CountDownLatch(1);
121	Thread t = new Thread(new CheckedInterruptedRunnable() {
122	public void realRun() throws InterruptedException {
123	assertTrue(l.getCount() > 0);
124	l.await(MEDIUM_DELAY_MS, MILLISECONDS);
125	}});
126
127	t.start();
128	delay(SHORT_DELAY_MS);
129	assertEquals(l.getCount(), 1);
130	t.interrupt();
131	t.join();
132	}
133
134	/**
135	* timed await times out if not counted down before timeout
136	*/
137	public void testAwaitTimeout() throws InterruptedException {
138	final CountDownLatch l = new CountDownLatch(1);
139	Thread t = new Thread(new CheckedRunnable() {
140	public void realRun() throws InterruptedException {
141	assertTrue(l.getCount() > 0);
142	assertFalse(l.await(SHORT_DELAY_MS, MILLISECONDS));
143	assertTrue(l.getCount() > 0);
144	}});
145
146	t.start();
147	assertEquals(l.getCount(), 1);
148	t.join();
149	}
150
151	/**
152	* toString indicates current count
153	*/
154	public void testToString() {
155	CountDownLatch s = new CountDownLatch(2);
156	assertTrue(s.toString().contains("Count = 2"));
157	s.countDown();
158	assertTrue(s.toString().contains("Count = 1"));
159	s.countDown();
160	assertTrue(s.toString().contains("Count = 0"));
161	}
162
163	}