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1
4 package com.tc.stats.counter;
5
6 import java.util.Random  ;
7
8 import EDU.oswego.cs.dl.util.concurrent.SynchronizedLong;
9 import EDU.oswego.cs.dl.util.concurrent.SynchronizedRef;
10 import junit.framework.TestCase;
11
12 public class CounterTest extends TestCase {
13
14 public void testInitialValue() {
15 Counter counter = new CounterImpl();
16 assertEquals(0L, counter.getValue());
17
18 counter = new CounterImpl(42L);
19 assertEquals(42L, counter.getValue());
20 }
21
22 public void testConcurrency() throws InterruptedException {
23 final Counter counter = new CounterImpl();
24 final SynchronizedLong local = new SynchronizedLong(0L);
25 final SynchronizedRef error = new SynchronizedRef(null);
26
27 Thread [] threads = new Thread [10];
28 for (int i = 0; i < threads.length; i++) {
29 threads[i] = new Thread () {
30 public void run() {
31 try {
32 Random random = new Random (hashCode());
33 for (int n = 0; n < 100000; n++) {
34 int operation = random.nextInt(4);
35
36 switch (operation) {
37 case 0: {
38 local.decrement();
39 counter.decrement();
40 break;
41 }
42 case 1: {
43 local.increment();
44 counter.increment();
45 break;
46 }
47 case 2: {
48 long amount = random.nextLong();
49 local.subtract(amount);
50 counter.decrement(amount);
51 break;
52 }
53 case 3: {
54 long amount = random.nextLong();
55 local.add(amount);
56 counter.increment(amount);
57 break;
58 }
59 default: {
60 throw new RuntimeException ("operation " + operation);
61 }
62 }
63 }
64 } catch (Throwable t) {
65 t.printStackTrace();
66 error.set(t);
67 }
68 }
69 };
70 threads[i].start();
71 }
72
73 for (int i = 0; i < threads.length; i++) {
74 threads[i].join();
75 }
76
77 if (error.get() != null) {
78 fail(error.get().toString());
79 }
80
81 assertEquals(local.get(), counter.getValue());
82 }
83
84
85 public void testMinMax() {
86 Counter counter = new CounterImpl();
87 assertEquals(0, counter.getMinValue());
88 assertEquals(0, counter.getMaxValue());
89
90 counter.increment();
91 assertEquals(0, counter.getMinValue());
92 assertEquals(1, counter.getMaxValue());
93
94 counter.decrement();
95 assertEquals(0, counter.getMinValue());
96 assertEquals(1, counter.getMaxValue());
97 counter.decrement();
98 assertEquals(-1, counter.getMinValue());
99 assertEquals(1, counter.getMaxValue());
100
101 counter.increment(10);
102 assertEquals(-1, counter.getMinValue());
103 assertEquals(9, counter.getMaxValue());
104
105 counter.decrement(20);
106 assertEquals(-11, counter.getMinValue());
107 assertEquals(9, counter.getMaxValue());
108
109 counter.setValue(100);
110 assertEquals(-11, counter.getMinValue());
111 assertEquals(100, counter.getMaxValue());
112
113 counter.setValue(-100);
114 assertEquals(-100, counter.getMinValue());
115 assertEquals(100, counter.getMaxValue());
116
117 counter.getAndSet(5);
118 assertEquals(-100, counter.getMinValue());
119 assertEquals(100, counter.getMaxValue());
120 }
121
122
123 public void test() {
124 Counter counter = new CounterImpl();
125 assertEquals(0L, counter.getValue());
126
127 counter.decrement();
128 assertEquals(-1L, counter.getValue());
129
130 counter.increment();
131 assertEquals(0L, counter.getValue());
132
133 counter.decrement(10L);
134 assertEquals(-10L, counter.getValue());
135
136 counter.increment(10L);
137 assertEquals(0L, counter.getValue());
138
139 counter.increment(-10L);
140 assertEquals(-10L, counter.getValue());
141
142 counter.decrement(-10L);
143 assertEquals(0L, counter.getValue());
144
145 counter.setValue(Long.MAX_VALUE);
146 assertEquals(Long.MAX_VALUE, counter.getValue());
147
148 counter.setValue(Long.MIN_VALUE);
149 assertEquals(Long.MIN_VALUE, counter.getValue());
150
151 counter.setValue(0L);
152 assertEquals(0L, counter.getValue());
153
154 counter.increment();
155 counter.increment();
156 counter.increment();
157 long value = counter.getAndSet(42L);
158 assertEquals(3L, value);
159 assertEquals(42L, counter.getValue());
160 }
161
162 }
163 |
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