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 java.util.concurrent.atomic.AtomicInteger;

import junit.framework.Test;
import junit.framework.TestSuite;

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(3, ai.get());
    }

    /**
     * repeated weakCompareAndSet succeeds in changing value when equal
     * to expected
     */
    public void testWeakCompareAndSet() {
        AtomicInteger ai = new AtomicInteger(1);
        do {} while (!ai.weakCompareAndSet(1, 2));
        do {} while (!ai.weakCompareAndSet(2, -4));
        assertEquals(-4, ai.get());
        do {} 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 x = new AtomicInteger();
        AtomicInteger y = serialClone(x);
        assertNotSame(x, y);
        x.set(22);
        AtomicInteger z = serialClone(x);
        assertEquals(22, x.get());
        assertEquals(0, y.get());
        assertEquals(22, z.get());
    }

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

    /**
     * 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:	1.27
Committed:	Wed Dec 31 19:21:20 2014 UTC (9 years, 4 months ago) by jsr166
Branch:	MAIN
Changes since 1.26:	+3 -3 lines
Log Message:	prefer do {} while (...); to while (...);
#	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	jsr166	1.22	import java.util.concurrent.atomic.AtomicInteger;
10	dl	1.1
11	jsr166	1.26	import junit.framework.Test;
12			import junit.framework.TestSuite;
13
14	dl	1.3	public class AtomicIntegerTest extends JSR166TestCase {
15	jsr166	1.20	public static void main(String[] args) {
16			junit.textui.TestRunner.run(suite());
17	dl	1.1	}
18			public static Test suite() {
19			return new TestSuite(AtomicIntegerTest.class);
20			}
21
22	jsr166	1.18	final int[] VALUES = {
23			Integer.MIN_VALUE, -1, 0, 1, 42, Integer.MAX_VALUE,
24			};
25
26	dl	1.4	/**
27	dl	1.5	* constructor initializes to given value
28	dl	1.4	*/
29	jsr166	1.14	public void testConstructor() {
30	dl	1.1	AtomicInteger ai = new AtomicInteger(1);
31	jsr166	1.23	assertEquals(1, ai.get());
32	dl	1.1	}
33
34	dl	1.4	/**
35	dl	1.7	* default constructed initializes to zero
36	dl	1.4	*/
37	jsr166	1.14	public void testConstructor2() {
38	dl	1.1	AtomicInteger ai = new AtomicInteger();
39	jsr166	1.23	assertEquals(0, ai.get());
40	dl	1.1	}
41
42	dl	1.4	/**
43	dl	1.11	* get returns the last value set
44			*/
45	jsr166	1.14	public void testGetSet() {
46	dl	1.11	AtomicInteger ai = new AtomicInteger(1);
47	jsr166	1.23	assertEquals(1, ai.get());
48	jsr166	1.17	ai.set(2);
49	jsr166	1.23	assertEquals(2, ai.get());
50	jsr166	1.17	ai.set(-3);
51	jsr166	1.23	assertEquals(-3, ai.get());
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	1.23	assertEquals(1, ai.get());
60	jsr166	1.17	ai.lazySet(2);
61	jsr166	1.23	assertEquals(2, ai.get());
62	jsr166	1.17	ai.lazySet(-3);
63	jsr166	1.23	assertEquals(-3, ai.get());
64	jsr166	1.19	}
65	jsr166	1.12
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	1.23	assertTrue(ai.compareAndSet(1, 2));
72			assertTrue(ai.compareAndSet(2, -4));
73			assertEquals(-4, ai.get());
74			assertFalse(ai.compareAndSet(-5, 7));
75			assertEquals(-4, 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	jsr166	1.24	assertEquals(3, ai.get());
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	1.27	do {} while (!ai.weakCompareAndSet(1, 2));
106			do {} while (!ai.weakCompareAndSet(2, -4));
107	jsr166	1.23	assertEquals(-4, ai.get());
108	jsr166	1.27	do {} while (!ai.weakCompareAndSet(-4, 7));
109	jsr166	1.23	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	1.23	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	1.23	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	1.23	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	1.23	assertEquals(1, ai.getAndIncrement());
149			assertEquals(2, ai.get());
150	jsr166	1.17	ai.set(-2);
151	jsr166	1.23	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	1.23	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	1.23	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	1.23	assertEquals(2, ai.incrementAndGet());
185			assertEquals(2, ai.get());
186	jsr166	1.17	ai.set(-2);
187	jsr166	1.23	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	jsr166	1.22	AtomicInteger x = new AtomicInteger();
198			AtomicInteger y = serialClone(x);
199	jsr166	1.25	assertNotSame(x, y);
200	jsr166	1.22	x.set(22);
201			AtomicInteger z = serialClone(x);
202			assertEquals(22, x.get());
203			assertEquals(0, y.get());
204			assertEquals(22, z.get());
205	dl	1.1	}
206
207	dl	1.8	/**
208			* toString returns current value.
209	jsr166	1.12	*/
210	dl	1.8	public void testToString() {
211			AtomicInteger ai = new AtomicInteger();
212	jsr166	1.18	assertEquals("0", ai.toString());
213			for (int x : VALUES) {
214			ai.set(x);
215	jsr166	1.24	assertEquals(Integer.toString(x), ai.toString());
216	dl	1.8	}
217			}
218	dl	1.1
219	dl	1.9	/**
220			* intValue returns current value.
221	jsr166	1.12	*/
222	dl	1.9	public void testIntValue() {
223			AtomicInteger ai = new AtomicInteger();
224	jsr166	1.18	assertEquals(0, ai.intValue());
225			for (int x : VALUES) {
226			ai.set(x);
227			assertEquals(x, ai.intValue());
228	dl	1.9	}
229			}
230
231			/**
232			* longValue returns current value.
233	jsr166	1.12	*/
234	dl	1.9	public void testLongValue() {
235			AtomicInteger ai = new AtomicInteger();
236	jsr166	1.18	assertEquals(0L, ai.longValue());
237			for (int x : VALUES) {
238			ai.set(x);
239			assertEquals((long)x, ai.longValue());
240	dl	1.9	}
241			}
242
243			/**
244			* floatValue returns current value.
245	jsr166	1.12	*/
246	dl	1.9	public void testFloatValue() {
247			AtomicInteger ai = new AtomicInteger();
248	jsr166	1.18	assertEquals(0.0f, ai.floatValue());
249			for (int x : VALUES) {
250			ai.set(x);
251			assertEquals((float)x, ai.floatValue());
252	dl	1.9	}
253			}
254
255			/**
256			* doubleValue returns current value.
257	jsr166	1.12	*/
258	dl	1.9	public void testDoubleValue() {
259			AtomicInteger ai = new AtomicInteger();
260	jsr166	1.18	assertEquals(0.0d, ai.doubleValue());
261			for (int x : VALUES) {
262			ai.set(x);
263			assertEquals((double)x, ai.doubleValue());
264	dl	1.9	}
265			}
266
267	dl	1.1	}