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 |
jsr166 |
1.5 |
import java.util.concurrent.CyclicBarrier; |
8 |
|
|
import java.util.concurrent.Executors; |
9 |
|
|
import java.util.concurrent.ExecutorService; |
10 |
dl |
1.1 |
import java.util.concurrent.atomic.LongAdder; |
11 |
|
|
|
12 |
jsr166 |
1.5 |
import junit.framework.Test; |
13 |
|
|
import junit.framework.TestSuite; |
14 |
|
|
|
15 |
dl |
1.1 |
public class LongAdderTest extends JSR166TestCase { |
16 |
|
|
public static void main(String[] args) { |
17 |
jsr166 |
1.6 |
main(suite(), args); |
18 |
dl |
1.1 |
} |
19 |
|
|
public static Test suite() { |
20 |
|
|
return new TestSuite(LongAdderTest.class); |
21 |
|
|
} |
22 |
|
|
|
23 |
|
|
/** |
24 |
|
|
* default constructed initializes to zero |
25 |
|
|
*/ |
26 |
|
|
public void testConstructor() { |
27 |
|
|
LongAdder ai = new LongAdder(); |
28 |
|
|
assertEquals(0, ai.sum()); |
29 |
|
|
} |
30 |
|
|
|
31 |
|
|
/** |
32 |
|
|
* add adds given value to current, and sum returns current value |
33 |
|
|
*/ |
34 |
|
|
public void testAddAndSum() { |
35 |
|
|
LongAdder ai = new LongAdder(); |
36 |
|
|
ai.add(2); |
37 |
|
|
assertEquals(2, ai.sum()); |
38 |
|
|
ai.add(-4); |
39 |
|
|
assertEquals(-2, ai.sum()); |
40 |
|
|
} |
41 |
|
|
|
42 |
|
|
/** |
43 |
|
|
* decrement decrements and sum returns current value |
44 |
|
|
*/ |
45 |
|
|
public void testDecrementAndsum() { |
46 |
|
|
LongAdder ai = new LongAdder(); |
47 |
|
|
ai.decrement(); |
48 |
|
|
assertEquals(-1, ai.sum()); |
49 |
|
|
ai.decrement(); |
50 |
|
|
assertEquals(-2, ai.sum()); |
51 |
|
|
} |
52 |
|
|
|
53 |
|
|
/** |
54 |
|
|
* incrementAndGet increments and returns current value |
55 |
|
|
*/ |
56 |
|
|
public void testIncrementAndsum() { |
57 |
|
|
LongAdder ai = new LongAdder(); |
58 |
|
|
ai.increment(); |
59 |
|
|
assertEquals(1, ai.sum()); |
60 |
|
|
ai.increment(); |
61 |
|
|
assertEquals(2, ai.sum()); |
62 |
|
|
} |
63 |
|
|
|
64 |
|
|
/** |
65 |
jsr166 |
1.7 |
* reset() causes subsequent sum() to return zero |
66 |
dl |
1.1 |
*/ |
67 |
|
|
public void testReset() { |
68 |
|
|
LongAdder ai = new LongAdder(); |
69 |
|
|
ai.add(2); |
70 |
|
|
assertEquals(2, ai.sum()); |
71 |
|
|
ai.reset(); |
72 |
|
|
assertEquals(0, ai.sum()); |
73 |
|
|
} |
74 |
|
|
|
75 |
|
|
/** |
76 |
jsr166 |
1.7 |
* sumThenReset() returns sum; subsequent sum() returns zero |
77 |
dl |
1.1 |
*/ |
78 |
|
|
public void testSumThenReset() { |
79 |
|
|
LongAdder ai = new LongAdder(); |
80 |
|
|
ai.add(2); |
81 |
|
|
assertEquals(2, ai.sum()); |
82 |
|
|
assertEquals(2, ai.sumThenReset()); |
83 |
|
|
assertEquals(0, ai.sum()); |
84 |
|
|
} |
85 |
|
|
|
86 |
|
|
/** |
87 |
jsr166 |
1.8 |
* a deserialized/reserialized adder holds same value |
88 |
dl |
1.1 |
*/ |
89 |
|
|
public void testSerialization() throws Exception { |
90 |
|
|
LongAdder x = new LongAdder(); |
91 |
|
|
LongAdder y = serialClone(x); |
92 |
jsr166 |
1.3 |
assertNotSame(x, y); |
93 |
dl |
1.1 |
x.add(-22); |
94 |
|
|
LongAdder z = serialClone(x); |
95 |
jsr166 |
1.3 |
assertNotSame(y, z); |
96 |
dl |
1.1 |
assertEquals(-22, x.sum()); |
97 |
|
|
assertEquals(0, y.sum()); |
98 |
|
|
assertEquals(-22, z.sum()); |
99 |
|
|
} |
100 |
|
|
|
101 |
|
|
/** |
102 |
|
|
* toString returns current value. |
103 |
|
|
*/ |
104 |
|
|
public void testToString() { |
105 |
|
|
LongAdder ai = new LongAdder(); |
106 |
|
|
assertEquals("0", ai.toString()); |
107 |
|
|
ai.increment(); |
108 |
|
|
assertEquals(Long.toString(1), ai.toString()); |
109 |
|
|
} |
110 |
|
|
|
111 |
|
|
/** |
112 |
|
|
* intValue returns current value. |
113 |
|
|
*/ |
114 |
|
|
public void testIntValue() { |
115 |
|
|
LongAdder ai = new LongAdder(); |
116 |
|
|
assertEquals(0, ai.intValue()); |
117 |
|
|
ai.increment(); |
118 |
|
|
assertEquals(1, ai.intValue()); |
119 |
|
|
} |
120 |
|
|
|
121 |
|
|
/** |
122 |
|
|
* longValue returns current value. |
123 |
|
|
*/ |
124 |
|
|
public void testLongValue() { |
125 |
|
|
LongAdder ai = new LongAdder(); |
126 |
|
|
assertEquals(0, ai.longValue()); |
127 |
|
|
ai.increment(); |
128 |
|
|
assertEquals(1, ai.longValue()); |
129 |
|
|
} |
130 |
|
|
|
131 |
|
|
/** |
132 |
|
|
* floatValue returns current value. |
133 |
|
|
*/ |
134 |
|
|
public void testFloatValue() { |
135 |
|
|
LongAdder ai = new LongAdder(); |
136 |
|
|
assertEquals(0.0f, ai.floatValue()); |
137 |
|
|
ai.increment(); |
138 |
|
|
assertEquals(1.0f, ai.floatValue()); |
139 |
|
|
} |
140 |
|
|
|
141 |
|
|
/** |
142 |
|
|
* doubleValue returns current value. |
143 |
|
|
*/ |
144 |
|
|
public void testDoubleValue() { |
145 |
|
|
LongAdder ai = new LongAdder(); |
146 |
|
|
assertEquals(0.0, ai.doubleValue()); |
147 |
|
|
ai.increment(); |
148 |
|
|
assertEquals(1.0, ai.doubleValue()); |
149 |
|
|
} |
150 |
|
|
|
151 |
|
|
/** |
152 |
|
|
* adds by multiple threads produce correct sum |
153 |
|
|
*/ |
154 |
jsr166 |
1.4 |
public void testAddAndSumMT() throws Throwable { |
155 |
dl |
1.1 |
final int incs = 1000000; |
156 |
|
|
final int nthreads = 4; |
157 |
|
|
final ExecutorService pool = Executors.newCachedThreadPool(); |
158 |
|
|
LongAdder a = new LongAdder(); |
159 |
jsr166 |
1.4 |
CyclicBarrier barrier = new CyclicBarrier(nthreads + 1); |
160 |
dl |
1.1 |
for (int i = 0; i < nthreads; ++i) |
161 |
jsr166 |
1.4 |
pool.execute(new AdderTask(a, barrier, incs)); |
162 |
|
|
barrier.await(); |
163 |
|
|
barrier.await(); |
164 |
dl |
1.1 |
long total = (long)nthreads * incs; |
165 |
|
|
long sum = a.sum(); |
166 |
|
|
assertEquals(sum, total); |
167 |
|
|
pool.shutdown(); |
168 |
|
|
} |
169 |
|
|
|
170 |
jsr166 |
1.2 |
static final class AdderTask implements Runnable { |
171 |
dl |
1.1 |
final LongAdder adder; |
172 |
jsr166 |
1.4 |
final CyclicBarrier barrier; |
173 |
dl |
1.1 |
final int incs; |
174 |
|
|
volatile long result; |
175 |
jsr166 |
1.4 |
AdderTask(LongAdder adder, CyclicBarrier barrier, int incs) { |
176 |
jsr166 |
1.2 |
this.adder = adder; |
177 |
jsr166 |
1.4 |
this.barrier = barrier; |
178 |
dl |
1.1 |
this.incs = incs; |
179 |
|
|
} |
180 |
|
|
|
181 |
|
|
public void run() { |
182 |
jsr166 |
1.4 |
try { |
183 |
|
|
barrier.await(); |
184 |
|
|
LongAdder a = adder; |
185 |
|
|
for (int i = 0; i < incs; ++i) |
186 |
|
|
a.add(1L); |
187 |
|
|
result = a.sum(); |
188 |
|
|
barrier.await(); |
189 |
|
|
} catch (Throwable t) { throw new Error(t); } |
190 |
dl |
1.1 |
} |
191 |
|
|
} |
192 |
|
|
|
193 |
|
|
} |