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 |
* Other contributors include Andrew Wright, Jeffrey Hayes, |
6 |
* Pat Fisher, Mike Judd. |
7 |
*/ |
8 |
|
9 |
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater; |
10 |
|
11 |
import junit.framework.Test; |
12 |
import junit.framework.TestSuite; |
13 |
|
14 |
public class AtomicIntegerFieldUpdaterTest extends JSR166TestCase { |
15 |
volatile int x = 0; |
16 |
int w; |
17 |
long z; |
18 |
public static void main(String[] args) { |
19 |
main(suite(), args); |
20 |
} |
21 |
public static Test suite() { |
22 |
return new TestSuite(AtomicIntegerFieldUpdaterTest.class); |
23 |
} |
24 |
|
25 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> updaterFor(String fieldName) { |
26 |
return AtomicIntegerFieldUpdater.newUpdater |
27 |
(AtomicIntegerFieldUpdaterTest.class, fieldName); |
28 |
} |
29 |
|
30 |
/** |
31 |
* Construction with non-existent field throws RuntimeException |
32 |
*/ |
33 |
public void testConstructor() { |
34 |
try { |
35 |
updaterFor("y"); |
36 |
shouldThrow(); |
37 |
} catch (RuntimeException success) { |
38 |
assertNotNull(success.getCause()); |
39 |
} |
40 |
} |
41 |
|
42 |
/** |
43 |
* construction with field not of given type throws IllegalArgumentException |
44 |
*/ |
45 |
public void testConstructor2() { |
46 |
try { |
47 |
updaterFor("z"); |
48 |
shouldThrow(); |
49 |
} catch (IllegalArgumentException success) {} |
50 |
} |
51 |
|
52 |
/** |
53 |
* construction with non-volatile field throws IllegalArgumentException |
54 |
*/ |
55 |
public void testConstructor3() { |
56 |
try { |
57 |
updaterFor("w"); |
58 |
shouldThrow(); |
59 |
} catch (IllegalArgumentException success) {} |
60 |
} |
61 |
|
62 |
/** |
63 |
* get returns the last value set or assigned |
64 |
*/ |
65 |
public void testGetSet() { |
66 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
67 |
a = updaterFor("x"); |
68 |
x = 1; |
69 |
assertEquals(1, a.get(this)); |
70 |
a.set(this, 2); |
71 |
assertEquals(2, a.get(this)); |
72 |
a.set(this, -3); |
73 |
assertEquals(-3, a.get(this)); |
74 |
} |
75 |
|
76 |
/** |
77 |
* get returns the last value lazySet by same thread |
78 |
*/ |
79 |
public void testGetLazySet() { |
80 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
81 |
a = updaterFor("x"); |
82 |
x = 1; |
83 |
assertEquals(1, a.get(this)); |
84 |
a.lazySet(this, 2); |
85 |
assertEquals(2, a.get(this)); |
86 |
a.lazySet(this, -3); |
87 |
assertEquals(-3, a.get(this)); |
88 |
} |
89 |
|
90 |
/** |
91 |
* compareAndSet succeeds in changing value if equal to expected else fails |
92 |
*/ |
93 |
public void testCompareAndSet() { |
94 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
95 |
a = updaterFor("x"); |
96 |
x = 1; |
97 |
assertTrue(a.compareAndSet(this, 1, 2)); |
98 |
assertTrue(a.compareAndSet(this, 2, -4)); |
99 |
assertEquals(-4, a.get(this)); |
100 |
assertFalse(a.compareAndSet(this, -5, 7)); |
101 |
assertEquals(-4, a.get(this)); |
102 |
assertTrue(a.compareAndSet(this, -4, 7)); |
103 |
assertEquals(7, a.get(this)); |
104 |
} |
105 |
|
106 |
/** |
107 |
* compareAndSet in one thread enables another waiting for value |
108 |
* to succeed |
109 |
*/ |
110 |
public void testCompareAndSetInMultipleThreads() throws Exception { |
111 |
x = 1; |
112 |
final AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
113 |
a = updaterFor("x"); |
114 |
|
115 |
Thread t = new Thread(new CheckedRunnable() { |
116 |
public void realRun() { |
117 |
while (!a.compareAndSet(AtomicIntegerFieldUpdaterTest.this, 2, 3)) |
118 |
Thread.yield(); |
119 |
}}); |
120 |
|
121 |
t.start(); |
122 |
assertTrue(a.compareAndSet(this, 1, 2)); |
123 |
t.join(LONG_DELAY_MS); |
124 |
assertFalse(t.isAlive()); |
125 |
assertEquals(3, a.get(this)); |
126 |
} |
127 |
|
128 |
/** |
129 |
* repeated weakCompareAndSet succeeds in changing value when equal |
130 |
* to expected |
131 |
*/ |
132 |
public void testWeakCompareAndSet() { |
133 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
134 |
a = updaterFor("x"); |
135 |
x = 1; |
136 |
do {} while (!a.weakCompareAndSet(this, 1, 2)); |
137 |
do {} while (!a.weakCompareAndSet(this, 2, -4)); |
138 |
assertEquals(-4, a.get(this)); |
139 |
do {} while (!a.weakCompareAndSet(this, -4, 7)); |
140 |
assertEquals(7, a.get(this)); |
141 |
} |
142 |
|
143 |
/** |
144 |
* getAndSet returns previous value and sets to given value |
145 |
*/ |
146 |
public void testGetAndSet() { |
147 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
148 |
a = updaterFor("x"); |
149 |
x = 1; |
150 |
assertEquals(1, a.getAndSet(this, 0)); |
151 |
assertEquals(0, a.getAndSet(this, -10)); |
152 |
assertEquals(-10, a.getAndSet(this, 1)); |
153 |
} |
154 |
|
155 |
/** |
156 |
* getAndAdd returns previous value and adds given value |
157 |
*/ |
158 |
public void testGetAndAdd() { |
159 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
160 |
a = updaterFor("x"); |
161 |
x = 1; |
162 |
assertEquals(1, a.getAndAdd(this, 2)); |
163 |
assertEquals(3, a.get(this)); |
164 |
assertEquals(3, a.getAndAdd(this, -4)); |
165 |
assertEquals(-1, a.get(this)); |
166 |
} |
167 |
|
168 |
/** |
169 |
* getAndDecrement returns previous value and decrements |
170 |
*/ |
171 |
public void testGetAndDecrement() { |
172 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
173 |
a = updaterFor("x"); |
174 |
x = 1; |
175 |
assertEquals(1, a.getAndDecrement(this)); |
176 |
assertEquals(0, a.getAndDecrement(this)); |
177 |
assertEquals(-1, a.getAndDecrement(this)); |
178 |
} |
179 |
|
180 |
/** |
181 |
* getAndIncrement returns previous value and increments |
182 |
*/ |
183 |
public void testGetAndIncrement() { |
184 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
185 |
a = updaterFor("x"); |
186 |
x = 1; |
187 |
assertEquals(1, a.getAndIncrement(this)); |
188 |
assertEquals(2, a.get(this)); |
189 |
a.set(this, -2); |
190 |
assertEquals(-2, a.getAndIncrement(this)); |
191 |
assertEquals(-1, a.getAndIncrement(this)); |
192 |
assertEquals(0, a.getAndIncrement(this)); |
193 |
assertEquals(1, a.get(this)); |
194 |
} |
195 |
|
196 |
/** |
197 |
* addAndGet adds given value to current, and returns current value |
198 |
*/ |
199 |
public void testAddAndGet() { |
200 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
201 |
a = updaterFor("x"); |
202 |
x = 1; |
203 |
assertEquals(3, a.addAndGet(this, 2)); |
204 |
assertEquals(3, a.get(this)); |
205 |
assertEquals(-1, a.addAndGet(this, -4)); |
206 |
assertEquals(-1, a.get(this)); |
207 |
} |
208 |
|
209 |
/** |
210 |
* decrementAndGet decrements and returns current value |
211 |
*/ |
212 |
public void testDecrementAndGet() { |
213 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
214 |
a = updaterFor("x"); |
215 |
x = 1; |
216 |
assertEquals(0, a.decrementAndGet(this)); |
217 |
assertEquals(-1, a.decrementAndGet(this)); |
218 |
assertEquals(-2, a.decrementAndGet(this)); |
219 |
assertEquals(-2, a.get(this)); |
220 |
} |
221 |
|
222 |
/** |
223 |
* incrementAndGet increments and returns current value |
224 |
*/ |
225 |
public void testIncrementAndGet() { |
226 |
AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a; |
227 |
a = updaterFor("x"); |
228 |
x = 1; |
229 |
assertEquals(2, a.incrementAndGet(this)); |
230 |
assertEquals(2, a.get(this)); |
231 |
a.set(this, -2); |
232 |
assertEquals(-1, a.incrementAndGet(this)); |
233 |
assertEquals(0, a.incrementAndGet(this)); |
234 |
assertEquals(1, a.incrementAndGet(this)); |
235 |
assertEquals(1, a.get(this)); |
236 |
} |
237 |
|
238 |
} |