test/tck/AtomicReferenceTest.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.concurrent.atomic.AtomicReference;

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

    /**
     * constructor initializes to given value
     */
    public void testConstructor() {
        AtomicReference ai = new AtomicReference(one);
        assertSame(one, ai.get());
    }

    /**
     * default constructed initializes to null
     */
    public void testConstructor2() {
        AtomicReference ai = new AtomicReference();
        assertNull(ai.get());
    }

    /**
     * get returns the last value set
     */
    public void testGetSet() {
        AtomicReference ai = new AtomicReference(one);
        assertSame(one, ai.get());
        ai.set(two);
        assertSame(two, ai.get());
        ai.set(m3);
        assertSame(m3, ai.get());
    }

    /**
     * get returns the last value lazySet in same thread
     */
    public void testGetLazySet() {
        AtomicReference ai = new AtomicReference(one);
        assertSame(one, ai.get());
        ai.lazySet(two);
        assertSame(two, ai.get());
        ai.lazySet(m3);
        assertSame(m3, ai.get());
    }

    /**
     * compareAndSet succeeds in changing value if equal to expected else fails
     */
    public void testCompareAndSet() {
        AtomicReference ai = new AtomicReference(one);
        assertTrue(ai.compareAndSet(one, two));
        assertTrue(ai.compareAndSet(two, m4));
        assertSame(m4, ai.get());
        assertFalse(ai.compareAndSet(m5, seven));
        assertSame(m4, ai.get());
        assertTrue(ai.compareAndSet(m4, seven));
        assertSame(seven, ai.get());
    }

    /**
     * compareAndSet in one thread enables another waiting for value
     * to succeed
     */
    public void testCompareAndSetInMultipleThreads() throws Exception {
        final AtomicReference ai = new AtomicReference(one);
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() {
                while (!ai.compareAndSet(two, three))
                    Thread.yield();
            }});

        t.start();
        assertTrue(ai.compareAndSet(one, two));
        t.join(LONG_DELAY_MS);
        assertFalse(t.isAlive());
        assertSame(ai.get(), three);
    }

    /**
     * repeated weakCompareAndSet succeeds in changing value when equal
     * to expected
     */
    public void testWeakCompareAndSet() {
        AtomicReference ai = new AtomicReference(one);
        while (!ai.weakCompareAndSet(one, two));
        while (!ai.weakCompareAndSet(two, m4));
        assertSame(m4, ai.get());
        while (!ai.weakCompareAndSet(m4, seven));
        assertSame(seven, ai.get());
    }

    /**
     * getAndSet returns previous value and sets to given value
     */
    public void testGetAndSet() {
        AtomicReference ai = new AtomicReference(one);
        assertSame(one, ai.getAndSet(zero));
        assertSame(zero, ai.getAndSet(m10));
        assertSame(m10, ai.getAndSet(one));
    }

    /**
     * a deserialized serialized atomic holds same value
     */
    public void testSerialization() throws Exception {
        AtomicReference x = new AtomicReference();
        AtomicReference y = serialClone(x);
        assertTrue(x != y);
        x.set(one);
        AtomicReference z = serialClone(x);
        assertEquals(one, x.get());
        assertEquals(null, y.get());
        assertEquals(one, z.get());
    }

    /**
     * toString returns current value.
     */
    public void testToString() {
        AtomicReference<Integer> ai = new AtomicReference<Integer>(one);
        assertEquals(ai.toString(), one.toString());
        ai.set(two);
        assertEquals(ai.toString(), two.toString());
    }

}
Revision:	1.19
Committed:	Fri Jun 10 20:01:21 2011 UTC (12 years, 10 months ago) by jsr166
Branch:	MAIN
Changes since 1.18:	+22 -22 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	1.17	* http://creativecommons.org/publicdomain/zero/1.0/
5	jsr166	1.9	* Other contributors include Andrew Wright, Jeffrey Hayes,
6			* Pat Fisher, Mike Judd.
7	dl	1.1	*/
8
9			import junit.framework.*;
10	jsr166	1.18	import java.util.concurrent.atomic.AtomicReference;
11	dl	1.1
12	dl	1.3	public class AtomicReferenceTest extends JSR166TestCase {
13	jsr166	1.16	public static void main(String[] args) {
14			junit.textui.TestRunner.run(suite());
15	dl	1.1	}
16			public static Test suite() {
17			return new TestSuite(AtomicReferenceTest.class);
18			}
19
20	dl	1.4	/**
21	dl	1.5	* constructor initializes to given value
22	dl	1.4	*/
23	jsr166	1.11	public void testConstructor() {
24	dl	1.1	AtomicReference ai = new AtomicReference(one);
25	jsr166	1.19	assertSame(one, ai.get());
26	dl	1.1	}
27
28	dl	1.4	/**
29	dl	1.5	* default constructed initializes to null
30	dl	1.4	*/
31	jsr166	1.11	public void testConstructor2() {
32	dl	1.1	AtomicReference ai = new AtomicReference();
33	jsr166	1.14	assertNull(ai.get());
34	dl	1.1	}
35
36	dl	1.4	/**
37	dl	1.5	* get returns the last value set
38	dl	1.4	*/
39	jsr166	1.11	public void testGetSet() {
40	dl	1.1	AtomicReference ai = new AtomicReference(one);
41	jsr166	1.19	assertSame(one, ai.get());
42	jsr166	1.14	ai.set(two);
43	jsr166	1.19	assertSame(two, ai.get());
44	jsr166	1.14	ai.set(m3);
45	jsr166	1.19	assertSame(m3, ai.get());
46	dl	1.1	}
47	dl	1.8
48			/**
49			* get returns the last value lazySet in same thread
50			*/
51	jsr166	1.11	public void testGetLazySet() {
52	dl	1.8	AtomicReference ai = new AtomicReference(one);
53	jsr166	1.19	assertSame(one, ai.get());
54	jsr166	1.14	ai.lazySet(two);
55	jsr166	1.19	assertSame(two, ai.get());
56	jsr166	1.14	ai.lazySet(m3);
57	jsr166	1.19	assertSame(m3, ai.get());
58	dl	1.8	}
59
60	dl	1.4	/**
61	dl	1.5	* compareAndSet succeeds in changing value if equal to expected else fails
62	dl	1.4	*/
63	jsr166	1.11	public void testCompareAndSet() {
64	dl	1.1	AtomicReference ai = new AtomicReference(one);
65	jsr166	1.19	assertTrue(ai.compareAndSet(one, two));
66			assertTrue(ai.compareAndSet(two, m4));
67			assertSame(m4, ai.get());
68			assertFalse(ai.compareAndSet(m5, seven));
69			assertSame(m4, ai.get());
70			assertTrue(ai.compareAndSet(m4, seven));
71			assertSame(seven, ai.get());
72	dl	1.1	}
73
74	dl	1.4	/**
75	dl	1.5	* compareAndSet in one thread enables another waiting for value
76			* to succeed
77			*/
78	jsr166	1.12	public void testCompareAndSetInMultipleThreads() throws Exception {
79	dl	1.5	final AtomicReference ai = new AtomicReference(one);
80	jsr166	1.13	Thread t = new Thread(new CheckedRunnable() {
81			public void realRun() {
82			while (!ai.compareAndSet(two, three))
83			Thread.yield();
84			}});
85	jsr166	1.12
86			t.start();
87			assertTrue(ai.compareAndSet(one, two));
88			t.join(LONG_DELAY_MS);
89			assertFalse(t.isAlive());
90	jsr166	1.15	assertSame(ai.get(), three);
91	dl	1.5	}
92
93			/**
94			* repeated weakCompareAndSet succeeds in changing value when equal
95	jsr166	1.9	* to expected
96	dl	1.4	*/
97	jsr166	1.11	public void testWeakCompareAndSet() {
98	dl	1.1	AtomicReference ai = new AtomicReference(one);
99	jsr166	1.19	while (!ai.weakCompareAndSet(one, two));
100			while (!ai.weakCompareAndSet(two, m4));
101			assertSame(m4, ai.get());
102			while (!ai.weakCompareAndSet(m4, seven));
103			assertSame(seven, ai.get());
104	dl	1.1	}
105
106	dl	1.4	/**
107	dl	1.5	* getAndSet returns previous value and sets to given value
108	dl	1.4	*/
109	jsr166	1.11	public void testGetAndSet() {
110	dl	1.1	AtomicReference ai = new AtomicReference(one);
111	jsr166	1.19	assertSame(one, ai.getAndSet(zero));
112			assertSame(zero, ai.getAndSet(m10));
113			assertSame(m10, ai.getAndSet(one));
114	dl	1.2	}
115
116	dl	1.4	/**
117	dl	1.5	* a deserialized serialized atomic holds same value
118	dl	1.4	*/
119	jsr166	1.12	public void testSerialization() throws Exception {
120	jsr166	1.18	AtomicReference x = new AtomicReference();
121			AtomicReference y = serialClone(x);
122			assertTrue(x != y);
123			x.set(one);
124			AtomicReference z = serialClone(x);
125			assertEquals(one, x.get());
126			assertEquals(null, y.get());
127			assertEquals(one, z.get());
128	dl	1.1	}
129
130	dl	1.7	/**
131			* toString returns current value.
132	jsr166	1.9	*/
133	dl	1.7	public void testToString() {
134	jsr166	1.9	AtomicReference<Integer> ai = new AtomicReference<Integer>(one);
135	dl	1.7	assertEquals(ai.toString(), one.toString());
136			ai.set(two);
137			assertEquals(ai.toString(), two.toString());
138			}
139
140	dl	1.1	}