test/tck/AtomicIntegerTest.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.*;
import java.io.*;

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

    final int[] VALUES = {
        Integer.MIN_VALUE, -1, 0, 1, 42, Integer.MAX_VALUE,
    };

    /**
     * constructor initializes to given value
     */
    public void testConstructor() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(1,ai.get());
    }

    /**
     * default constructed initializes to zero
     */
    public void testConstructor2() {
        AtomicInteger ai = new AtomicInteger();
        assertEquals(0,ai.get());
    }

    /**
     * get returns the last value set
     */
    public void testGetSet() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(1,ai.get());
        ai.set(2);
        assertEquals(2,ai.get());
        ai.set(-3);
        assertEquals(-3,ai.get());
    }

    /**
     * get returns the last value lazySet in same thread
     */
    public void testGetLazySet() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(1,ai.get());
        ai.lazySet(2);
        assertEquals(2,ai.get());
        ai.lazySet(-3);
        assertEquals(-3,ai.get());
    }

    /**
     * compareAndSet succeeds in changing value if equal to expected else fails
     */
    public void testCompareAndSet() {
        AtomicInteger ai = new AtomicInteger(1);
        assertTrue(ai.compareAndSet(1,2));
        assertTrue(ai.compareAndSet(2,-4));
        assertEquals(-4,ai.get());
        assertFalse(ai.compareAndSet(-5,7));
        assertEquals(-4,ai.get());
        assertTrue(ai.compareAndSet(-4,7));
        assertEquals(7,ai.get());
    }

    /**
     * compareAndSet in one thread enables another waiting for value
     * to succeed
     */
    public void testCompareAndSetInMultipleThreads() throws Exception {
        final AtomicInteger ai = new AtomicInteger(1);
        Thread t = new Thread(new CheckedRunnable() {
            public void realRun() {
                while (!ai.compareAndSet(2, 3))
                    Thread.yield();
            }});

        t.start();
        assertTrue(ai.compareAndSet(1, 2));
        t.join(LONG_DELAY_MS);
        assertFalse(t.isAlive());
        assertEquals(ai.get(), 3);
    }

    /**
     * repeated weakCompareAndSet succeeds in changing value when equal
     * to expected
     */
    public void testWeakCompareAndSet() {
        AtomicInteger ai = new AtomicInteger(1);
        while (!ai.weakCompareAndSet(1,2));
        while (!ai.weakCompareAndSet(2,-4));
        assertEquals(-4,ai.get());
        while (!ai.weakCompareAndSet(-4,7));
        assertEquals(7,ai.get());
    }

    /**
     * getAndSet returns previous value and sets to given value
     */
    public void testGetAndSet() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(1,ai.getAndSet(0));
        assertEquals(0,ai.getAndSet(-10));
        assertEquals(-10,ai.getAndSet(1));
    }

    /**
     * getAndAdd returns previous value and adds given value
     */
    public void testGetAndAdd() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(1,ai.getAndAdd(2));
        assertEquals(3,ai.get());
        assertEquals(3,ai.getAndAdd(-4));
        assertEquals(-1,ai.get());
    }

    /**
     * getAndDecrement returns previous value and decrements
     */
    public void testGetAndDecrement() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(1,ai.getAndDecrement());
        assertEquals(0,ai.getAndDecrement());
        assertEquals(-1,ai.getAndDecrement());
    }

    /**
     * getAndIncrement returns previous value and increments
     */
    public void testGetAndIncrement() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(1,ai.getAndIncrement());
        assertEquals(2,ai.get());
        ai.set(-2);
        assertEquals(-2,ai.getAndIncrement());
        assertEquals(-1,ai.getAndIncrement());
        assertEquals(0,ai.getAndIncrement());
        assertEquals(1,ai.get());
    }

    /**
     * addAndGet adds given value to current, and returns current value
     */
    public void testAddAndGet() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(3,ai.addAndGet(2));
        assertEquals(3,ai.get());
        assertEquals(-1,ai.addAndGet(-4));
        assertEquals(-1,ai.get());
    }

    /**
     * decrementAndGet decrements and returns current value
     */
    public void testDecrementAndGet() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(0,ai.decrementAndGet());
        assertEquals(-1,ai.decrementAndGet());
        assertEquals(-2,ai.decrementAndGet());
        assertEquals(-2,ai.get());
    }

    /**
     * incrementAndGet increments and returns current value
     */
    public void testIncrementAndGet() {
        AtomicInteger ai = new AtomicInteger(1);
        assertEquals(2,ai.incrementAndGet());
        assertEquals(2,ai.get());
        ai.set(-2);
        assertEquals(-1,ai.incrementAndGet());
        assertEquals(0,ai.incrementAndGet());
        assertEquals(1,ai.incrementAndGet());
        assertEquals(1,ai.get());
    }

    /**
     * a deserialized serialized atomic holds same value
     */
    public void testSerialization() throws Exception {
        AtomicInteger l = new AtomicInteger();

        l.set(22);
        ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
        ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
        out.writeObject(l);
        out.close();

        ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
        ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
        AtomicInteger r = (AtomicInteger) in.readObject();
        assertEquals(l.get(), r.get());
    }

    /**
     * toString returns current value.
     */
    public void testToString() {
        AtomicInteger ai = new AtomicInteger();
        assertEquals("0", ai.toString());
        for (int x : VALUES) {
            ai.set(x);
            assertEquals(ai.toString(), Integer.toString(x));
        }
    }

    /**
     * intValue returns current value.
     */
    public void testIntValue() {
        AtomicInteger ai = new AtomicInteger();
        assertEquals(0, ai.intValue());
        for (int x : VALUES) {
            ai.set(x);
            assertEquals(x, ai.intValue());
        }
    }

    /**
     * longValue returns current value.
     */
    public void testLongValue() {
        AtomicInteger ai = new AtomicInteger();
        assertEquals(0L, ai.longValue());
        for (int x : VALUES) {
            ai.set(x);
            assertEquals((long)x, ai.longValue());
        }
    }

    /**
     * floatValue returns current value.
     */
    public void testFloatValue() {
        AtomicInteger ai = new AtomicInteger();
        assertEquals(0.0f, ai.floatValue());
        for (int x : VALUES) {
            ai.set(x);
            assertEquals((float)x, ai.floatValue());
        }
    }

    /**
     * doubleValue returns current value.
     */
    public void testDoubleValue() {
        AtomicInteger ai = new AtomicInteger();
        assertEquals(0.0d, ai.doubleValue());
        for (int x : VALUES) {
            ai.set(x);
            assertEquals((double)x, ai.doubleValue());
        }
    }

}
Revision:	1.21
Committed:	Tue Mar 15 19:47:06 2011 UTC (13 years, 1 month ago) by jsr166
Branch:	MAIN
CVS Tags:	release-1_7_0
Changes since 1.20:	+1 -1 lines
Log Message:	Update Creative Commons license URL in legal notices
#	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	1.21	* http://creativecommons.org/publicdomain/zero/1.0/
5	jsr166	1.12	* 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.concurrent.atomic.*;
11	dl	1.2	import java.io.*;
12	dl	1.1
13	dl	1.3	public class AtomicIntegerTest extends JSR166TestCase {
14	jsr166	1.20	public static void main(String[] args) {
15			junit.textui.TestRunner.run(suite());
16	dl	1.1	}
17			public static Test suite() {
18			return new TestSuite(AtomicIntegerTest.class);
19			}
20
21	jsr166	1.18	final int[] VALUES = {
22			Integer.MIN_VALUE, -1, 0, 1, 42, Integer.MAX_VALUE,
23			};
24
25	dl	1.4	/**
26	dl	1.5	* constructor initializes to given value
27	dl	1.4	*/
28	jsr166	1.14	public void testConstructor() {
29	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
30	jsr166	1.17	assertEquals(1,ai.get());
31	dl	1.1	}
32
33	dl	1.4	/**
34	dl	1.7	* default constructed initializes to zero
35	dl	1.4	*/
36	jsr166	1.14	public void testConstructor2() {
37	dl	1.1	AtomicInteger ai = new AtomicInteger();
38	jsr166	1.17	assertEquals(0,ai.get());
39	dl	1.1	}
40
41	dl	1.4	/**
42	dl	1.11	* get returns the last value set
43			*/
44	jsr166	1.14	public void testGetSet() {
45	dl	1.11	AtomicInteger ai = new AtomicInteger(1);
46	jsr166	1.17	assertEquals(1,ai.get());
47			ai.set(2);
48			assertEquals(2,ai.get());
49			ai.set(-3);
50			assertEquals(-3,ai.get());
51	dl	1.11	}
52
53			/**
54	dl	1.10	* get returns the last value lazySet in same thread
55	dl	1.4	*/
56	jsr166	1.14	public void testGetLazySet() {
57	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
58	jsr166	1.17	assertEquals(1,ai.get());
59			ai.lazySet(2);
60			assertEquals(2,ai.get());
61			ai.lazySet(-3);
62			assertEquals(-3,ai.get());
63	jsr166	1.19	}
64	jsr166	1.12
65	dl	1.4	/**
66	dl	1.5	* compareAndSet succeeds in changing value if equal to expected else fails
67	dl	1.4	*/
68	jsr166	1.14	public void testCompareAndSet() {
69	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
70	jsr166	1.17	assertTrue(ai.compareAndSet(1,2));
71			assertTrue(ai.compareAndSet(2,-4));
72			assertEquals(-4,ai.get());
73			assertFalse(ai.compareAndSet(-5,7));
74	jsr166	1.19	assertEquals(-4,ai.get());
75	jsr166	1.17	assertTrue(ai.compareAndSet(-4,7));
76			assertEquals(7,ai.get());
77	dl	1.1	}
78
79	dl	1.4	/**
80	dl	1.5	* compareAndSet in one thread enables another waiting for value
81			* to succeed
82			*/
83	jsr166	1.15	public void testCompareAndSetInMultipleThreads() throws Exception {
84	dl	1.5	final AtomicInteger ai = new AtomicInteger(1);
85	jsr166	1.16	Thread t = new Thread(new CheckedRunnable() {
86			public void realRun() {
87			while (!ai.compareAndSet(2, 3))
88			Thread.yield();
89			}});
90	jsr166	1.15
91			t.start();
92			assertTrue(ai.compareAndSet(1, 2));
93			t.join(LONG_DELAY_MS);
94			assertFalse(t.isAlive());
95			assertEquals(ai.get(), 3);
96	dl	1.5	}
97
98			/**
99			* repeated weakCompareAndSet succeeds in changing value when equal
100	jsr166	1.12	* to expected
101	dl	1.4	*/
102	jsr166	1.14	public void testWeakCompareAndSet() {
103	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
104	jsr166	1.17	while (!ai.weakCompareAndSet(1,2));
105			while (!ai.weakCompareAndSet(2,-4));
106			assertEquals(-4,ai.get());
107	jsr166	1.13	while (!ai.weakCompareAndSet(-4,7));
108	jsr166	1.17	assertEquals(7,ai.get());
109	dl	1.1	}
110
111	dl	1.4	/**
112	dl	1.5	* getAndSet returns previous value and sets to given value
113	dl	1.4	*/
114	jsr166	1.14	public void testGetAndSet() {
115	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
116	jsr166	1.17	assertEquals(1,ai.getAndSet(0));
117			assertEquals(0,ai.getAndSet(-10));
118			assertEquals(-10,ai.getAndSet(1));
119	dl	1.1	}
120
121	dl	1.4	/**
122	dl	1.5	* getAndAdd returns previous value and adds given value
123	dl	1.4	*/
124	jsr166	1.14	public void testGetAndAdd() {
125	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
126	jsr166	1.17	assertEquals(1,ai.getAndAdd(2));
127			assertEquals(3,ai.get());
128			assertEquals(3,ai.getAndAdd(-4));
129			assertEquals(-1,ai.get());
130	dl	1.1	}
131
132	dl	1.4	/**
133	dl	1.5	* getAndDecrement returns previous value and decrements
134	dl	1.4	*/
135	jsr166	1.14	public void testGetAndDecrement() {
136	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
137	jsr166	1.17	assertEquals(1,ai.getAndDecrement());
138			assertEquals(0,ai.getAndDecrement());
139			assertEquals(-1,ai.getAndDecrement());
140	dl	1.1	}
141
142	dl	1.4	/**
143	dl	1.5	* getAndIncrement returns previous value and increments
144	dl	1.4	*/
145	jsr166	1.14	public void testGetAndIncrement() {
146	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
147	jsr166	1.17	assertEquals(1,ai.getAndIncrement());
148			assertEquals(2,ai.get());
149			ai.set(-2);
150			assertEquals(-2,ai.getAndIncrement());
151			assertEquals(-1,ai.getAndIncrement());
152			assertEquals(0,ai.getAndIncrement());
153			assertEquals(1,ai.get());
154	dl	1.1	}
155
156	dl	1.4	/**
157	dl	1.5	* addAndGet adds given value to current, and returns current value
158	dl	1.4	*/
159	jsr166	1.14	public void testAddAndGet() {
160	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
161	jsr166	1.17	assertEquals(3,ai.addAndGet(2));
162			assertEquals(3,ai.get());
163			assertEquals(-1,ai.addAndGet(-4));
164			assertEquals(-1,ai.get());
165	dl	1.1	}
166
167	dl	1.4	/**
168	dl	1.5	* decrementAndGet decrements and returns current value
169	dl	1.4	*/
170	jsr166	1.14	public void testDecrementAndGet() {
171	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
172	jsr166	1.17	assertEquals(0,ai.decrementAndGet());
173			assertEquals(-1,ai.decrementAndGet());
174			assertEquals(-2,ai.decrementAndGet());
175			assertEquals(-2,ai.get());
176	dl	1.1	}
177
178	dl	1.4	/**
179	dl	1.5	* incrementAndGet increments and returns current value
180	dl	1.4	*/
181	jsr166	1.14	public void testIncrementAndGet() {
182	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
183	jsr166	1.17	assertEquals(2,ai.incrementAndGet());
184			assertEquals(2,ai.get());
185			ai.set(-2);
186			assertEquals(-1,ai.incrementAndGet());
187			assertEquals(0,ai.incrementAndGet());
188			assertEquals(1,ai.incrementAndGet());
189			assertEquals(1,ai.get());
190	dl	1.2	}
191
192	dl	1.4	/**
193	dl	1.5	* a deserialized serialized atomic holds same value
194	dl	1.4	*/
195	jsr166	1.15	public void testSerialization() throws Exception {
196	dl	1.2	AtomicInteger l = new AtomicInteger();
197
198	jsr166	1.15	l.set(22);
199			ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
200			ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
201			out.writeObject(l);
202			out.close();
203
204			ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
205			ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
206			AtomicInteger r = (AtomicInteger) in.readObject();
207			assertEquals(l.get(), r.get());
208	dl	1.1	}
209
210	dl	1.8	/**
211			* toString returns current value.
212	jsr166	1.12	*/
213	dl	1.8	public void testToString() {
214			AtomicInteger ai = new AtomicInteger();
215	jsr166	1.18	assertEquals("0", ai.toString());
216			for (int x : VALUES) {
217			ai.set(x);
218			assertEquals(ai.toString(), Integer.toString(x));
219	dl	1.8	}
220			}
221	dl	1.1
222	dl	1.9	/**
223			* intValue returns current value.
224	jsr166	1.12	*/
225	dl	1.9	public void testIntValue() {
226			AtomicInteger ai = new AtomicInteger();
227	jsr166	1.18	assertEquals(0, ai.intValue());
228			for (int x : VALUES) {
229			ai.set(x);
230			assertEquals(x, ai.intValue());
231	dl	1.9	}
232			}
233
234			/**
235			* longValue returns current value.
236	jsr166	1.12	*/
237	dl	1.9	public void testLongValue() {
238			AtomicInteger ai = new AtomicInteger();
239	jsr166	1.18	assertEquals(0L, ai.longValue());
240			for (int x : VALUES) {
241			ai.set(x);
242			assertEquals((long)x, ai.longValue());
243	dl	1.9	}
244			}
245
246			/**
247			* floatValue returns current value.
248	jsr166	1.12	*/
249	dl	1.9	public void testFloatValue() {
250			AtomicInteger ai = new AtomicInteger();
251	jsr166	1.18	assertEquals(0.0f, ai.floatValue());
252			for (int x : VALUES) {
253			ai.set(x);
254			assertEquals((float)x, ai.floatValue());
255	dl	1.9	}
256			}
257
258			/**
259			* doubleValue returns current value.
260	jsr166	1.12	*/
261	dl	1.9	public void testDoubleValue() {
262			AtomicInteger ai = new AtomicInteger();
263	jsr166	1.18	assertEquals(0.0d, ai.doubleValue());
264			for (int x : VALUES) {
265			ai.set(x);
266			assertEquals((double)x, ai.doubleValue());
267	dl	1.9	}
268			}
269
270	dl	1.1	}