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/licenses/publicdomain
 * 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));
        assertFalse((7 == 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:	1.18
Committed:	Sun Nov 22 18:55:56 2009 UTC (14 years, 5 months ago) by jsr166
Branch:	MAIN
Changes since 1.17:	+24 -18 lines
Log Message:	More thorough testing of values
#	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			* http://creativecommons.org/licenses/publicdomain
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	dl	1.1	public static void main (String[] args) {
15			junit.textui.TestRunner.run (suite());
16			}
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	jsr166	1.12
52	dl	1.11	}
53
54			/**
55	dl	1.10	* get returns the last value lazySet in same thread
56	dl	1.4	*/
57	jsr166	1.14	public void testGetLazySet() {
58	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
59	jsr166	1.17	assertEquals(1,ai.get());
60			ai.lazySet(2);
61			assertEquals(2,ai.get());
62			ai.lazySet(-3);
63			assertEquals(-3,ai.get());
64	jsr166	1.12
65	dl	1.1	}
66	dl	1.4	/**
67	dl	1.5	* compareAndSet succeeds in changing value if equal to expected else fails
68	dl	1.4	*/
69	jsr166	1.14	public void testCompareAndSet() {
70	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
71	jsr166	1.17	assertTrue(ai.compareAndSet(1,2));
72			assertTrue(ai.compareAndSet(2,-4));
73			assertEquals(-4,ai.get());
74			assertFalse(ai.compareAndSet(-5,7));
75			assertFalse((7 == ai.get()));
76			assertTrue(ai.compareAndSet(-4,7));
77			assertEquals(7,ai.get());
78	dl	1.1	}
79
80	dl	1.4	/**
81	dl	1.5	* compareAndSet in one thread enables another waiting for value
82			* to succeed
83			*/
84	jsr166	1.15	public void testCompareAndSetInMultipleThreads() throws Exception {
85	dl	1.5	final AtomicInteger ai = new AtomicInteger(1);
86	jsr166	1.16	Thread t = new Thread(new CheckedRunnable() {
87			public void realRun() {
88			while (!ai.compareAndSet(2, 3))
89			Thread.yield();
90			}});
91	jsr166	1.15
92			t.start();
93			assertTrue(ai.compareAndSet(1, 2));
94			t.join(LONG_DELAY_MS);
95			assertFalse(t.isAlive());
96			assertEquals(ai.get(), 3);
97	dl	1.5	}
98
99			/**
100			* repeated weakCompareAndSet succeeds in changing value when equal
101	jsr166	1.12	* to expected
102	dl	1.4	*/
103	jsr166	1.14	public void testWeakCompareAndSet() {
104	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
105	jsr166	1.17	while (!ai.weakCompareAndSet(1,2));
106			while (!ai.weakCompareAndSet(2,-4));
107			assertEquals(-4,ai.get());
108	jsr166	1.13	while (!ai.weakCompareAndSet(-4,7));
109	jsr166	1.17	assertEquals(7,ai.get());
110	dl	1.1	}
111
112	dl	1.4	/**
113	dl	1.5	* getAndSet returns previous value and sets to given value
114	dl	1.4	*/
115	jsr166	1.14	public void testGetAndSet() {
116	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
117	jsr166	1.17	assertEquals(1,ai.getAndSet(0));
118			assertEquals(0,ai.getAndSet(-10));
119			assertEquals(-10,ai.getAndSet(1));
120	dl	1.1	}
121
122	dl	1.4	/**
123	dl	1.5	* getAndAdd returns previous value and adds given value
124	dl	1.4	*/
125	jsr166	1.14	public void testGetAndAdd() {
126	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
127	jsr166	1.17	assertEquals(1,ai.getAndAdd(2));
128			assertEquals(3,ai.get());
129			assertEquals(3,ai.getAndAdd(-4));
130			assertEquals(-1,ai.get());
131	dl	1.1	}
132
133	dl	1.4	/**
134	dl	1.5	* getAndDecrement returns previous value and decrements
135	dl	1.4	*/
136	jsr166	1.14	public void testGetAndDecrement() {
137	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
138	jsr166	1.17	assertEquals(1,ai.getAndDecrement());
139			assertEquals(0,ai.getAndDecrement());
140			assertEquals(-1,ai.getAndDecrement());
141	dl	1.1	}
142
143	dl	1.4	/**
144	dl	1.5	* getAndIncrement returns previous value and increments
145	dl	1.4	*/
146	jsr166	1.14	public void testGetAndIncrement() {
147	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
148	jsr166	1.17	assertEquals(1,ai.getAndIncrement());
149			assertEquals(2,ai.get());
150			ai.set(-2);
151			assertEquals(-2,ai.getAndIncrement());
152			assertEquals(-1,ai.getAndIncrement());
153			assertEquals(0,ai.getAndIncrement());
154			assertEquals(1,ai.get());
155	dl	1.1	}
156
157	dl	1.4	/**
158	dl	1.5	* addAndGet adds given value to current, and returns current value
159	dl	1.4	*/
160	jsr166	1.14	public void testAddAndGet() {
161	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
162	jsr166	1.17	assertEquals(3,ai.addAndGet(2));
163			assertEquals(3,ai.get());
164			assertEquals(-1,ai.addAndGet(-4));
165			assertEquals(-1,ai.get());
166	dl	1.1	}
167
168	dl	1.4	/**
169	dl	1.5	* decrementAndGet decrements and returns current value
170	dl	1.4	*/
171	jsr166	1.14	public void testDecrementAndGet() {
172	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
173	jsr166	1.17	assertEquals(0,ai.decrementAndGet());
174			assertEquals(-1,ai.decrementAndGet());
175			assertEquals(-2,ai.decrementAndGet());
176			assertEquals(-2,ai.get());
177	dl	1.1	}
178
179	dl	1.4	/**
180	dl	1.5	* incrementAndGet increments and returns current value
181	dl	1.4	*/
182	jsr166	1.14	public void testIncrementAndGet() {
183	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
184	jsr166	1.17	assertEquals(2,ai.incrementAndGet());
185			assertEquals(2,ai.get());
186			ai.set(-2);
187			assertEquals(-1,ai.incrementAndGet());
188			assertEquals(0,ai.incrementAndGet());
189			assertEquals(1,ai.incrementAndGet());
190			assertEquals(1,ai.get());
191	dl	1.2	}
192
193	dl	1.4	/**
194	dl	1.5	* a deserialized serialized atomic holds same value
195	dl	1.4	*/
196	jsr166	1.15	public void testSerialization() throws Exception {
197	dl	1.2	AtomicInteger l = new AtomicInteger();
198
199	jsr166	1.15	l.set(22);
200			ByteArrayOutputStream bout = new ByteArrayOutputStream(10000);
201			ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout));
202			out.writeObject(l);
203			out.close();
204
205			ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray());
206			ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin));
207			AtomicInteger r = (AtomicInteger) in.readObject();
208			assertEquals(l.get(), r.get());
209	dl	1.1	}
210
211	dl	1.8	/**
212			* toString returns current value.
213	jsr166	1.12	*/
214	dl	1.8	public void testToString() {
215			AtomicInteger ai = new AtomicInteger();
216	jsr166	1.18	assertEquals("0", ai.toString());
217			for (int x : VALUES) {
218			ai.set(x);
219			assertEquals(ai.toString(), Integer.toString(x));
220	dl	1.8	}
221			}
222	dl	1.1
223	dl	1.9	/**
224			* intValue returns current value.
225	jsr166	1.12	*/
226	dl	1.9	public void testIntValue() {
227			AtomicInteger ai = new AtomicInteger();
228	jsr166	1.18	assertEquals(0, ai.intValue());
229			for (int x : VALUES) {
230			ai.set(x);
231			assertEquals(x, ai.intValue());
232	dl	1.9	}
233			}
234
235			/**
236			* longValue returns current value.
237	jsr166	1.12	*/
238	dl	1.9	public void testLongValue() {
239			AtomicInteger ai = new AtomicInteger();
240	jsr166	1.18	assertEquals(0L, ai.longValue());
241			for (int x : VALUES) {
242			ai.set(x);
243			assertEquals((long)x, ai.longValue());
244	dl	1.9	}
245			}
246
247			/**
248			* floatValue returns current value.
249	jsr166	1.12	*/
250	dl	1.9	public void testFloatValue() {
251			AtomicInteger ai = new AtomicInteger();
252	jsr166	1.18	assertEquals(0.0f, ai.floatValue());
253			for (int x : VALUES) {
254			ai.set(x);
255			assertEquals((float)x, ai.floatValue());
256	dl	1.9	}
257			}
258
259			/**
260			* doubleValue returns current value.
261	jsr166	1.12	*/
262	dl	1.9	public void testDoubleValue() {
263			AtomicInteger ai = new AtomicInteger();
264	jsr166	1.18	assertEquals(0.0d, ai.doubleValue());
265			for (int x : VALUES) {
266			ai.set(x);
267			assertEquals((double)x, ai.doubleValue());
268	dl	1.9	}
269			}
270
271	dl	1.1	}