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 java.util.concurrent.atomic.AtomicLong; 12 13 import junit.framework.Test; 14 import junit.framework.TestSuite; 15 16 public class AtomicLongTest extends JSR166TestCase { 17 // android-note: Removed because the CTS runner does a bad job of 18 // retrying tests that have suite() declarations. 19 // 20 // public static void main(String[] args) { 21 // main(suite(), args); 22 // } 23 // public static Test suite() { 24 // return new TestSuite(AtomicLongTest.class); 25 // } 26 27 final long[] VALUES = { 28 Long.MIN_VALUE, 29 Integer.MIN_VALUE, -1, 0, 1, 42, Integer.MAX_VALUE, 30 Long.MAX_VALUE, 31 }; 32 33 /** 34 * constructor initializes to given value 35 */ 36 public void testConstructor() { 37 AtomicLong ai = new AtomicLong(1); 38 assertEquals(1, ai.get()); 39 } 40 41 /** 42 * default constructed initializes to zero 43 */ 44 public void testConstructor2() { 45 AtomicLong ai = new AtomicLong(); 46 assertEquals(0, ai.get()); 47 } 48 49 /** 50 * get returns the last value set 51 */ 52 public void testGetSet() { 53 AtomicLong ai = new AtomicLong(1); 54 assertEquals(1, ai.get()); 55 ai.set(2); 56 assertEquals(2, ai.get()); 57 ai.set(-3); 58 assertEquals(-3, ai.get()); 59 } 60 61 /** 62 * get returns the last value lazySet in same thread 63 */ 64 public void testGetLazySet() { 65 AtomicLong ai = new AtomicLong(1); 66 assertEquals(1, ai.get()); 67 ai.lazySet(2); 68 assertEquals(2, ai.get()); 69 ai.lazySet(-3); 70 assertEquals(-3, ai.get()); 71 } 72 73 /** 74 * compareAndSet succeeds in changing value if equal to expected else fails 75 */ 76 public void testCompareAndSet() { 77 AtomicLong ai = new AtomicLong(1); 78 assertTrue(ai.compareAndSet(1, 2)); 79 assertTrue(ai.compareAndSet(2, -4)); 80 assertEquals(-4, ai.get()); 81 assertFalse(ai.compareAndSet(-5, 7)); 82 assertEquals(-4, ai.get()); 83 assertTrue(ai.compareAndSet(-4, 7)); 84 assertEquals(7, ai.get()); 85 } 86 87 /** 88 * compareAndSet in one thread enables another waiting for value 89 * to succeed 90 */ 91 public void testCompareAndSetInMultipleThreads() throws Exception { 92 final AtomicLong ai = new AtomicLong(1); 93 Thread t = new Thread(new CheckedRunnable() { 94 public void realRun() { 95 while (!ai.compareAndSet(2, 3)) 96 Thread.yield(); 97 }}); 98 99 t.start(); 100 assertTrue(ai.compareAndSet(1, 2)); 101 t.join(LONG_DELAY_MS); 102 assertFalse(t.isAlive()); 103 assertEquals(3, ai.get()); 104 } 105 106 /** 107 * repeated weakCompareAndSet succeeds in changing value when equal 108 * to expected 109 */ 110 public void testWeakCompareAndSet() { 111 AtomicLong ai = new AtomicLong(1); 112 do {} while (!ai.weakCompareAndSet(1, 2)); 113 do {} while (!ai.weakCompareAndSet(2, -4)); 114 assertEquals(-4, ai.get()); 115 do {} while (!ai.weakCompareAndSet(-4, 7)); 116 assertEquals(7, ai.get()); 117 } 118 119 /** 120 * getAndSet returns previous value and sets to given value 121 */ 122 public void testGetAndSet() { 123 AtomicLong ai = new AtomicLong(1); 124 assertEquals(1, ai.getAndSet(0)); 125 assertEquals(0, ai.getAndSet(-10)); 126 assertEquals(-10, ai.getAndSet(1)); 127 } 128 129 /** 130 * getAndAdd returns previous value and adds given value 131 */ 132 public void testGetAndAdd() { 133 AtomicLong ai = new AtomicLong(1); 134 assertEquals(1, ai.getAndAdd(2)); 135 assertEquals(3, ai.get()); 136 assertEquals(3, ai.getAndAdd(-4)); 137 assertEquals(-1, ai.get()); 138 } 139 140 /** 141 * getAndDecrement returns previous value and decrements 142 */ 143 public void testGetAndDecrement() { 144 AtomicLong ai = new AtomicLong(1); 145 assertEquals(1, ai.getAndDecrement()); 146 assertEquals(0, ai.getAndDecrement()); 147 assertEquals(-1, ai.getAndDecrement()); 148 } 149 150 /** 151 * getAndIncrement returns previous value and increments 152 */ 153 public void testGetAndIncrement() { 154 AtomicLong ai = new AtomicLong(1); 155 assertEquals(1, ai.getAndIncrement()); 156 assertEquals(2, ai.get()); 157 ai.set(-2); 158 assertEquals(-2, ai.getAndIncrement()); 159 assertEquals(-1, ai.getAndIncrement()); 160 assertEquals(0, ai.getAndIncrement()); 161 assertEquals(1, ai.get()); 162 } 163 164 /** 165 * addAndGet adds given value to current, and returns current value 166 */ 167 public void testAddAndGet() { 168 AtomicLong ai = new AtomicLong(1); 169 assertEquals(3, ai.addAndGet(2)); 170 assertEquals(3, ai.get()); 171 assertEquals(-1, ai.addAndGet(-4)); 172 assertEquals(-1, ai.get()); 173 } 174 175 /** 176 * decrementAndGet decrements and returns current value 177 */ 178 public void testDecrementAndGet() { 179 AtomicLong ai = new AtomicLong(1); 180 assertEquals(0, ai.decrementAndGet()); 181 assertEquals(-1, ai.decrementAndGet()); 182 assertEquals(-2, ai.decrementAndGet()); 183 assertEquals(-2, ai.get()); 184 } 185 186 /** 187 * incrementAndGet increments and returns current value 188 */ 189 public void testIncrementAndGet() { 190 AtomicLong ai = new AtomicLong(1); 191 assertEquals(2, ai.incrementAndGet()); 192 assertEquals(2, ai.get()); 193 ai.set(-2); 194 assertEquals(-1, ai.incrementAndGet()); 195 assertEquals(0, ai.incrementAndGet()); 196 assertEquals(1, ai.incrementAndGet()); 197 assertEquals(1, ai.get()); 198 } 199 200 /** 201 * a deserialized serialized atomic holds same value 202 */ 203 public void testSerialization() throws Exception { 204 AtomicLong x = new AtomicLong(); 205 AtomicLong y = serialClone(x); 206 assertNotSame(x, y); 207 x.set(-22); 208 AtomicLong z = serialClone(x); 209 assertNotSame(y, z); 210 assertEquals(-22, x.get()); 211 assertEquals(0, y.get()); 212 assertEquals(-22, z.get()); 213 } 214 215 /** 216 * toString returns current value. 217 */ 218 public void testToString() { 219 AtomicLong ai = new AtomicLong(); 220 assertEquals("0", ai.toString()); 221 for (long x : VALUES) { 222 ai.set(x); 223 assertEquals(Long.toString(x), ai.toString()); 224 } 225 } 226 227 /** 228 * intValue returns current value. 229 */ 230 public void testIntValue() { 231 AtomicLong ai = new AtomicLong(); 232 assertEquals(0, ai.intValue()); 233 for (long x : VALUES) { 234 ai.set(x); 235 assertEquals((int)x, ai.intValue()); 236 } 237 } 238 239 /** 240 * longValue returns current value. 241 */ 242 public void testLongValue() { 243 AtomicLong ai = new AtomicLong(); 244 assertEquals(0L, ai.longValue()); 245 for (long x : VALUES) { 246 ai.set(x); 247 assertEquals(x, ai.longValue()); 248 } 249 } 250 251 /** 252 * floatValue returns current value. 253 */ 254 public void testFloatValue() { 255 AtomicLong ai = new AtomicLong(); 256 assertEquals(0.0f, ai.floatValue()); 257 for (long x : VALUES) { 258 ai.set(x); 259 assertEquals((float)x, ai.floatValue()); 260 } 261 } 262 263 /** 264 * doubleValue returns current value. 265 */ 266 public void testDoubleValue() { 267 AtomicLong ai = new AtomicLong(); 268 assertEquals(0.0d, ai.doubleValue()); 269 for (long x : VALUES) { 270 ai.set(x); 271 assertEquals((double)x, ai.doubleValue()); 272 } 273 } 274 275 } 276
