test/tck/LongAdderTest.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/
 */

import junit.framework.*;
import java.util.concurrent.*;
import java.util.concurrent.atomic.LongAdder;

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

    /**
     * default constructed initializes to zero
     */
    public void testConstructor() {
        LongAdder ai = new LongAdder();
        assertEquals(0, ai.sum());
    }

    /**
     * add adds given value to current, and sum returns current value
     */
    public void testAddAndSum() {
        LongAdder ai = new LongAdder();
        ai.add(2);
        assertEquals(2, ai.sum());
        ai.add(-4);
        assertEquals(-2, ai.sum());
    }

    /**
     * decrement decrements and sum returns current value
     */
    public void testDecrementAndsum() {
        LongAdder ai = new LongAdder();
        ai.decrement();
        assertEquals(-1, ai.sum());
        ai.decrement();
        assertEquals(-2, ai.sum());
    }

    /**
     * incrementAndGet increments and returns current value
     */
    public void testIncrementAndsum() {
        LongAdder ai = new LongAdder();
        ai.increment();
        assertEquals(1, ai.sum());
        ai.increment();
        assertEquals(2, ai.sum());
    }

    /**
     * reset zeroes sum
     */
    public void testReset() {
        LongAdder ai = new LongAdder();
        ai.add(2);
        assertEquals(2, ai.sum());
        ai.reset();
        assertEquals(0, ai.sum());
    }

    /**
     * sumThenReset returns sum then zeros
     */
    public void testSumThenReset() {
        LongAdder ai = new LongAdder();
        ai.add(2);
        assertEquals(2, ai.sum());
        assertEquals(2, ai.sumThenReset());
        assertEquals(0, ai.sum());
    }

    /**
     * a deserialized serialized adder holds same value
     */
    public void testSerialization() throws Exception {
        LongAdder x = new LongAdder();
        LongAdder y = serialClone(x);
        assertNotSame(x, y);
        x.add(-22);
        LongAdder z = serialClone(x);
        assertNotSame(y, z);
        assertEquals(-22, x.sum());
        assertEquals(0, y.sum());
        assertEquals(-22, z.sum());
    }

    /**
     * toString returns current value.
     */
    public void testToString() {
        LongAdder ai = new LongAdder();
        assertEquals("0", ai.toString());
        ai.increment();
        assertEquals(Long.toString(1), ai.toString());
    }

    /**
     * intValue returns current value.
     */
    public void testIntValue() {
        LongAdder ai = new LongAdder();
        assertEquals(0, ai.intValue());
        ai.increment();
        assertEquals(1, ai.intValue());
    }

    /**
     * longValue returns current value.
     */
    public void testLongValue() {
        LongAdder ai = new LongAdder();
        assertEquals(0, ai.longValue());
        ai.increment();
        assertEquals(1, ai.longValue());
    }

    /**
     * floatValue returns current value.
     */
    public void testFloatValue() {
        LongAdder ai = new LongAdder();
        assertEquals(0.0f, ai.floatValue());
        ai.increment();
        assertEquals(1.0f, ai.floatValue());
    }

    /**
     * doubleValue returns current value.
     */
    public void testDoubleValue() {
        LongAdder ai = new LongAdder();
        assertEquals(0.0, ai.doubleValue());
        ai.increment();
        assertEquals(1.0, ai.doubleValue());
    }

    /**
     * adds by multiple threads produce correct sum
     */
    public void testAddAndSumMT() throws Throwable {
        final int incs = 1000000;
        final int nthreads = 4;
        final ExecutorService pool = Executors.newCachedThreadPool();
        LongAdder a = new LongAdder();
        CyclicBarrier barrier = new CyclicBarrier(nthreads + 1);
        for (int i = 0; i < nthreads; ++i)
            pool.execute(new AdderTask(a, barrier, incs));
        barrier.await();
        barrier.await();
        long total = (long)nthreads * incs;
        long sum = a.sum();
        assertEquals(sum, total);
        pool.shutdown();
    }

    static final class AdderTask implements Runnable {
        final LongAdder adder;
        final CyclicBarrier barrier;
        final int incs;
        volatile long result;
        AdderTask(LongAdder adder, CyclicBarrier barrier, int incs) {
            this.adder = adder;
            this.barrier = barrier;
            this.incs = incs;
        }

        public void run() {
            try {
                barrier.await();
                LongAdder a = adder;
                for (int i = 0; i < incs; ++i)
                    a.add(1L);
                result = a.sum();
                barrier.await();
            } catch (Throwable t) { throw new Error(t); }
        }
    }

}
Revision:	1.4
Committed:	Sun Jul 14 19:49:01 2013 UTC (10 years, 9 months ago) by jsr166
Branch:	MAIN
Changes since 1.3:	+16 -14 lines
Log Message:	backport to java 6, to help jsr166e
#	User	Rev	Content
1	dl	1.1	/*
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			*/
6
7			import junit.framework.*;
8			import java.util.concurrent.*;
9			import java.util.concurrent.atomic.LongAdder;
10
11			public class LongAdderTest extends JSR166TestCase {
12			public static void main(String[] args) {
13			junit.textui.TestRunner.run(suite());
14			}
15			public static Test suite() {
16			return new TestSuite(LongAdderTest.class);
17			}
18
19			/**
20			* default constructed initializes to zero
21			*/
22			public void testConstructor() {
23			LongAdder ai = new LongAdder();
24			assertEquals(0, ai.sum());
25			}
26
27			/**
28			* add adds given value to current, and sum returns current value
29			*/
30			public void testAddAndSum() {
31			LongAdder ai = new LongAdder();
32			ai.add(2);
33			assertEquals(2, ai.sum());
34			ai.add(-4);
35			assertEquals(-2, ai.sum());
36			}
37
38			/**
39			* decrement decrements and sum returns current value
40			*/
41			public void testDecrementAndsum() {
42			LongAdder ai = new LongAdder();
43			ai.decrement();
44			assertEquals(-1, ai.sum());
45			ai.decrement();
46			assertEquals(-2, ai.sum());
47			}
48
49			/**
50			* incrementAndGet increments and returns current value
51			*/
52			public void testIncrementAndsum() {
53			LongAdder ai = new LongAdder();
54			ai.increment();
55			assertEquals(1, ai.sum());
56			ai.increment();
57			assertEquals(2, ai.sum());
58			}
59
60			/**
61			* reset zeroes sum
62			*/
63			public void testReset() {
64			LongAdder ai = new LongAdder();
65			ai.add(2);
66			assertEquals(2, ai.sum());
67			ai.reset();
68			assertEquals(0, ai.sum());
69			}
70
71			/**
72			* sumThenReset returns sum then zeros
73			*/
74			public void testSumThenReset() {
75			LongAdder ai = new LongAdder();
76			ai.add(2);
77			assertEquals(2, ai.sum());
78			assertEquals(2, ai.sumThenReset());
79			assertEquals(0, ai.sum());
80			}
81
82			/**
83			* a deserialized serialized adder holds same value
84			*/
85			public void testSerialization() throws Exception {
86			LongAdder x = new LongAdder();
87			LongAdder y = serialClone(x);
88	jsr166	1.3	assertNotSame(x, y);
89	dl	1.1	x.add(-22);
90			LongAdder z = serialClone(x);
91	jsr166	1.3	assertNotSame(y, z);
92	dl	1.1	assertEquals(-22, x.sum());
93			assertEquals(0, y.sum());
94			assertEquals(-22, z.sum());
95			}
96
97			/**
98			* toString returns current value.
99			*/
100			public void testToString() {
101			LongAdder ai = new LongAdder();
102			assertEquals("0", ai.toString());
103			ai.increment();
104			assertEquals(Long.toString(1), ai.toString());
105			}
106
107			/**
108			* intValue returns current value.
109			*/
110			public void testIntValue() {
111			LongAdder ai = new LongAdder();
112			assertEquals(0, ai.intValue());
113			ai.increment();
114			assertEquals(1, ai.intValue());
115			}
116
117			/**
118			* longValue returns current value.
119			*/
120			public void testLongValue() {
121			LongAdder ai = new LongAdder();
122			assertEquals(0, ai.longValue());
123			ai.increment();
124			assertEquals(1, ai.longValue());
125			}
126
127			/**
128			* floatValue returns current value.
129			*/
130			public void testFloatValue() {
131			LongAdder ai = new LongAdder();
132			assertEquals(0.0f, ai.floatValue());
133			ai.increment();
134			assertEquals(1.0f, ai.floatValue());
135			}
136
137			/**
138			* doubleValue returns current value.
139			*/
140			public void testDoubleValue() {
141			LongAdder ai = new LongAdder();
142			assertEquals(0.0, ai.doubleValue());
143			ai.increment();
144			assertEquals(1.0, ai.doubleValue());
145			}
146
147			/**
148			* adds by multiple threads produce correct sum
149			*/
150	jsr166	1.4	public void testAddAndSumMT() throws Throwable {
151	dl	1.1	final int incs = 1000000;
152			final int nthreads = 4;
153			final ExecutorService pool = Executors.newCachedThreadPool();
154			LongAdder a = new LongAdder();
155	jsr166	1.4	CyclicBarrier barrier = new CyclicBarrier(nthreads + 1);
156	dl	1.1	for (int i = 0; i < nthreads; ++i)
157	jsr166	1.4	pool.execute(new AdderTask(a, barrier, incs));
158			barrier.await();
159			barrier.await();
160	dl	1.1	long total = (long)nthreads * incs;
161			long sum = a.sum();
162			assertEquals(sum, total);
163			pool.shutdown();
164			}
165
166	jsr166	1.2	static final class AdderTask implements Runnable {
167	dl	1.1	final LongAdder adder;
168	jsr166	1.4	final CyclicBarrier barrier;
169	dl	1.1	final int incs;
170			volatile long result;
171	jsr166	1.4	AdderTask(LongAdder adder, CyclicBarrier barrier, int incs) {
172	jsr166	1.2	this.adder = adder;
173	jsr166	1.4	this.barrier = barrier;
174	dl	1.1	this.incs = incs;
175			}
176
177			public void run() {
178	jsr166	1.4	try {
179			barrier.await();
180			LongAdder a = adder;
181			for (int i = 0; i < incs; ++i)
182			a.add(1L);
183			result = a.sum();
184			barrier.await();
185			} catch (Throwable t) { throw new Error(t); }
186	dl	1.1	}
187			}
188
189			}