Calin Juravle | 8f0d92b | 2013-08-01 17:26:00 +0100 | [diff] [blame] | 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 | package jsr166; |
| 10 | |
| 11 | import junit.framework.*; |
| 12 | import java.util.concurrent.atomic.AtomicInteger; |
| 13 | |
| 14 | public class AtomicIntegerTest extends JSR166TestCase { |
| 15 | |
| 16 | final int[] VALUES = { |
| 17 | Integer.MIN_VALUE, -1, 0, 1, 42, Integer.MAX_VALUE, |
| 18 | }; |
| 19 | |
| 20 | /** |
| 21 | * constructor initializes to given value |
| 22 | */ |
| 23 | public void testConstructor() { |
| 24 | AtomicInteger ai = new AtomicInteger(1); |
| 25 | assertEquals(1, ai.get()); |
| 26 | } |
| 27 | |
| 28 | /** |
| 29 | * default constructed initializes to zero |
| 30 | */ |
| 31 | public void testConstructor2() { |
| 32 | AtomicInteger ai = new AtomicInteger(); |
| 33 | assertEquals(0, ai.get()); |
| 34 | } |
| 35 | |
| 36 | /** |
| 37 | * get returns the last value set |
| 38 | */ |
| 39 | public void testGetSet() { |
| 40 | AtomicInteger ai = new AtomicInteger(1); |
| 41 | assertEquals(1, ai.get()); |
| 42 | ai.set(2); |
| 43 | assertEquals(2, ai.get()); |
| 44 | ai.set(-3); |
| 45 | assertEquals(-3, ai.get()); |
| 46 | } |
| 47 | |
| 48 | /** |
| 49 | * get returns the last value lazySet in same thread |
| 50 | */ |
| 51 | public void testGetLazySet() { |
| 52 | AtomicInteger ai = new AtomicInteger(1); |
| 53 | assertEquals(1, ai.get()); |
| 54 | ai.lazySet(2); |
| 55 | assertEquals(2, ai.get()); |
| 56 | ai.lazySet(-3); |
| 57 | assertEquals(-3, ai.get()); |
| 58 | } |
| 59 | |
| 60 | /** |
| 61 | * compareAndSet succeeds in changing value if equal to expected else fails |
| 62 | */ |
| 63 | public void testCompareAndSet() { |
| 64 | AtomicInteger ai = new AtomicInteger(1); |
| 65 | assertTrue(ai.compareAndSet(1, 2)); |
| 66 | assertTrue(ai.compareAndSet(2, -4)); |
| 67 | assertEquals(-4, ai.get()); |
| 68 | assertFalse(ai.compareAndSet(-5, 7)); |
| 69 | assertEquals(-4, ai.get()); |
| 70 | assertTrue(ai.compareAndSet(-4, 7)); |
| 71 | assertEquals(7, ai.get()); |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * compareAndSet in one thread enables another waiting for value |
| 76 | * to succeed |
| 77 | */ |
| 78 | public void testCompareAndSetInMultipleThreads() throws Exception { |
| 79 | final AtomicInteger ai = new AtomicInteger(1); |
| 80 | Thread t = new Thread(new CheckedRunnable() { |
| 81 | public void realRun() { |
| 82 | while (!ai.compareAndSet(2, 3)) |
| 83 | Thread.yield(); |
| 84 | }}); |
| 85 | |
| 86 | t.start(); |
| 87 | assertTrue(ai.compareAndSet(1, 2)); |
| 88 | t.join(LONG_DELAY_MS); |
| 89 | assertFalse(t.isAlive()); |
| 90 | assertEquals(3, ai.get()); |
| 91 | } |
| 92 | |
| 93 | /** |
| 94 | * repeated weakCompareAndSet succeeds in changing value when equal |
| 95 | * to expected |
| 96 | */ |
| 97 | public void testWeakCompareAndSet() { |
| 98 | AtomicInteger ai = new AtomicInteger(1); |
| 99 | while (!ai.weakCompareAndSet(1, 2)); |
| 100 | while (!ai.weakCompareAndSet(2, -4)); |
| 101 | assertEquals(-4, ai.get()); |
| 102 | while (!ai.weakCompareAndSet(-4, 7)); |
| 103 | assertEquals(7, ai.get()); |
| 104 | } |
| 105 | |
| 106 | /** |
| 107 | * getAndSet returns previous value and sets to given value |
| 108 | */ |
| 109 | public void testGetAndSet() { |
| 110 | AtomicInteger ai = new AtomicInteger(1); |
| 111 | assertEquals(1, ai.getAndSet(0)); |
| 112 | assertEquals(0, ai.getAndSet(-10)); |
| 113 | assertEquals(-10, ai.getAndSet(1)); |
| 114 | } |
| 115 | |
| 116 | /** |
| 117 | * getAndAdd returns previous value and adds given value |
| 118 | */ |
| 119 | public void testGetAndAdd() { |
| 120 | AtomicInteger ai = new AtomicInteger(1); |
| 121 | assertEquals(1, ai.getAndAdd(2)); |
| 122 | assertEquals(3, ai.get()); |
| 123 | assertEquals(3, ai.getAndAdd(-4)); |
| 124 | assertEquals(-1, ai.get()); |
| 125 | } |
| 126 | |
| 127 | /** |
| 128 | * getAndDecrement returns previous value and decrements |
| 129 | */ |
| 130 | public void testGetAndDecrement() { |
| 131 | AtomicInteger ai = new AtomicInteger(1); |
| 132 | assertEquals(1, ai.getAndDecrement()); |
| 133 | assertEquals(0, ai.getAndDecrement()); |
| 134 | assertEquals(-1, ai.getAndDecrement()); |
| 135 | } |
| 136 | |
| 137 | /** |
| 138 | * getAndIncrement returns previous value and increments |
| 139 | */ |
| 140 | public void testGetAndIncrement() { |
| 141 | AtomicInteger ai = new AtomicInteger(1); |
| 142 | assertEquals(1, ai.getAndIncrement()); |
| 143 | assertEquals(2, ai.get()); |
| 144 | ai.set(-2); |
| 145 | assertEquals(-2, ai.getAndIncrement()); |
| 146 | assertEquals(-1, ai.getAndIncrement()); |
| 147 | assertEquals(0, ai.getAndIncrement()); |
| 148 | assertEquals(1, ai.get()); |
| 149 | } |
| 150 | |
| 151 | /** |
| 152 | * addAndGet adds given value to current, and returns current value |
| 153 | */ |
| 154 | public void testAddAndGet() { |
| 155 | AtomicInteger ai = new AtomicInteger(1); |
| 156 | assertEquals(3, ai.addAndGet(2)); |
| 157 | assertEquals(3, ai.get()); |
| 158 | assertEquals(-1, ai.addAndGet(-4)); |
| 159 | assertEquals(-1, ai.get()); |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * decrementAndGet decrements and returns current value |
| 164 | */ |
| 165 | public void testDecrementAndGet() { |
| 166 | AtomicInteger ai = new AtomicInteger(1); |
| 167 | assertEquals(0, ai.decrementAndGet()); |
| 168 | assertEquals(-1, ai.decrementAndGet()); |
| 169 | assertEquals(-2, ai.decrementAndGet()); |
| 170 | assertEquals(-2, ai.get()); |
| 171 | } |
| 172 | |
| 173 | /** |
| 174 | * incrementAndGet increments and returns current value |
| 175 | */ |
| 176 | public void testIncrementAndGet() { |
| 177 | AtomicInteger ai = new AtomicInteger(1); |
| 178 | assertEquals(2, ai.incrementAndGet()); |
| 179 | assertEquals(2, ai.get()); |
| 180 | ai.set(-2); |
| 181 | assertEquals(-1, ai.incrementAndGet()); |
| 182 | assertEquals(0, ai.incrementAndGet()); |
| 183 | assertEquals(1, ai.incrementAndGet()); |
| 184 | assertEquals(1, ai.get()); |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * a deserialized serialized atomic holds same value |
| 189 | */ |
| 190 | public void testSerialization() throws Exception { |
| 191 | AtomicInteger x = new AtomicInteger(); |
| 192 | AtomicInteger y = serialClone(x); |
| 193 | assertNotSame(x, y); |
| 194 | x.set(22); |
| 195 | AtomicInteger z = serialClone(x); |
| 196 | assertEquals(22, x.get()); |
| 197 | assertEquals(0, y.get()); |
| 198 | assertEquals(22, z.get()); |
| 199 | } |
| 200 | |
| 201 | /** |
| 202 | * toString returns current value. |
| 203 | */ |
| 204 | public void testToString() { |
| 205 | AtomicInteger ai = new AtomicInteger(); |
| 206 | assertEquals("0", ai.toString()); |
| 207 | for (int x : VALUES) { |
| 208 | ai.set(x); |
| 209 | assertEquals(Integer.toString(x), ai.toString()); |
| 210 | } |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * intValue returns current value. |
| 215 | */ |
| 216 | public void testIntValue() { |
| 217 | AtomicInteger ai = new AtomicInteger(); |
| 218 | assertEquals(0, ai.intValue()); |
| 219 | for (int x : VALUES) { |
| 220 | ai.set(x); |
| 221 | assertEquals(x, ai.intValue()); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | /** |
| 226 | * longValue returns current value. |
| 227 | */ |
| 228 | public void testLongValue() { |
| 229 | AtomicInteger ai = new AtomicInteger(); |
| 230 | assertEquals(0L, ai.longValue()); |
| 231 | for (int x : VALUES) { |
| 232 | ai.set(x); |
| 233 | assertEquals((long)x, ai.longValue()); |
| 234 | } |
| 235 | } |
| 236 | |
| 237 | /** |
| 238 | * floatValue returns current value. |
| 239 | */ |
| 240 | public void testFloatValue() { |
| 241 | AtomicInteger ai = new AtomicInteger(); |
| 242 | assertEquals(0.0f, ai.floatValue()); |
| 243 | for (int x : VALUES) { |
| 244 | ai.set(x); |
| 245 | assertEquals((float)x, ai.floatValue()); |
| 246 | } |
| 247 | } |
| 248 | |
| 249 | /** |
| 250 | * doubleValue returns current value. |
| 251 | */ |
| 252 | public void testDoubleValue() { |
| 253 | AtomicInteger ai = new AtomicInteger(); |
| 254 | assertEquals(0.0d, ai.doubleValue()); |
| 255 | for (int x : VALUES) { |
| 256 | ai.set(x); |
| 257 | assertEquals((double)x, ai.doubleValue()); |
| 258 | } |
| 259 | } |
| 260 | |
| 261 | } |