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.Arrays; |
| 13 | import java.util.concurrent.atomic.AtomicLongArray; |
| 14 | |
| 15 | public class AtomicLongArrayTest extends JSR166TestCase { |
| 16 | |
| 17 | /** |
| 18 | * constructor creates array of given size with all elements zero |
| 19 | */ |
| 20 | public void testConstructor() { |
| 21 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 22 | for (int i = 0; i < SIZE; i++) |
| 23 | assertEquals(0, aa.get(i)); |
| 24 | } |
| 25 | |
| 26 | /** |
| 27 | * constructor with null array throws NPE |
| 28 | */ |
| 29 | public void testConstructor2NPE() { |
| 30 | try { |
| 31 | long[] a = null; |
| 32 | AtomicLongArray aa = new AtomicLongArray(a); |
| 33 | shouldThrow(); |
| 34 | } catch (NullPointerException success) {} |
| 35 | } |
| 36 | |
| 37 | /** |
| 38 | * constructor with array is of same size and has all elements |
| 39 | */ |
| 40 | public void testConstructor2() { |
| 41 | long[] a = { 17L, 3L, -42L, 99L, -7L }; |
| 42 | AtomicLongArray aa = new AtomicLongArray(a); |
| 43 | assertEquals(a.length, aa.length()); |
| 44 | for (int i = 0; i < a.length; i++) |
| 45 | assertEquals(a[i], aa.get(i)); |
| 46 | } |
| 47 | |
| 48 | /** |
| 49 | * get and set for out of bound indices throw IndexOutOfBoundsException |
| 50 | */ |
| 51 | public void testIndexing() { |
| 52 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 53 | for (int index : new int[] { -1, SIZE }) { |
| 54 | try { |
| 55 | aa.get(index); |
| 56 | shouldThrow(); |
| 57 | } catch (IndexOutOfBoundsException success) {} |
| 58 | try { |
| 59 | aa.set(index, 1); |
| 60 | shouldThrow(); |
| 61 | } catch (IndexOutOfBoundsException success) {} |
| 62 | try { |
| 63 | aa.lazySet(index, 1); |
| 64 | shouldThrow(); |
| 65 | } catch (IndexOutOfBoundsException success) {} |
| 66 | try { |
| 67 | aa.compareAndSet(index, 1, 2); |
| 68 | shouldThrow(); |
| 69 | } catch (IndexOutOfBoundsException success) {} |
| 70 | try { |
| 71 | aa.weakCompareAndSet(index, 1, 2); |
| 72 | shouldThrow(); |
| 73 | } catch (IndexOutOfBoundsException success) {} |
| 74 | try { |
| 75 | aa.getAndAdd(index, 1); |
| 76 | shouldThrow(); |
| 77 | } catch (IndexOutOfBoundsException success) {} |
| 78 | try { |
| 79 | aa.addAndGet(index, 1); |
| 80 | shouldThrow(); |
| 81 | } catch (IndexOutOfBoundsException success) {} |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * get returns the last value set at index |
| 87 | */ |
| 88 | public void testGetSet() { |
| 89 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 90 | for (int i = 0; i < SIZE; i++) { |
| 91 | aa.set(i, 1); |
| 92 | assertEquals(1, aa.get(i)); |
| 93 | aa.set(i, 2); |
| 94 | assertEquals(2, aa.get(i)); |
| 95 | aa.set(i, -3); |
| 96 | assertEquals(-3, aa.get(i)); |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | /** |
| 101 | * get returns the last value lazySet at index by same thread |
| 102 | */ |
| 103 | public void testGetLazySet() { |
| 104 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 105 | for (int i = 0; i < SIZE; i++) { |
| 106 | aa.lazySet(i, 1); |
| 107 | assertEquals(1, aa.get(i)); |
| 108 | aa.lazySet(i, 2); |
| 109 | assertEquals(2, aa.get(i)); |
| 110 | aa.lazySet(i, -3); |
| 111 | assertEquals(-3, aa.get(i)); |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | /** |
| 116 | * compareAndSet succeeds in changing value if equal to expected else fails |
| 117 | */ |
| 118 | public void testCompareAndSet() { |
| 119 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 120 | for (int i = 0; i < SIZE; i++) { |
| 121 | aa.set(i, 1); |
| 122 | assertTrue(aa.compareAndSet(i, 1, 2)); |
| 123 | assertTrue(aa.compareAndSet(i, 2, -4)); |
| 124 | assertEquals(-4, aa.get(i)); |
| 125 | assertFalse(aa.compareAndSet(i, -5, 7)); |
| 126 | assertEquals(-4, aa.get(i)); |
| 127 | assertTrue(aa.compareAndSet(i, -4, 7)); |
| 128 | assertEquals(7, aa.get(i)); |
| 129 | } |
| 130 | } |
| 131 | |
| 132 | /** |
| 133 | * compareAndSet in one thread enables another waiting for value |
| 134 | * to succeed |
| 135 | */ |
| 136 | public void testCompareAndSetInMultipleThreads() throws InterruptedException { |
| 137 | final AtomicLongArray a = new AtomicLongArray(1); |
| 138 | a.set(0, 1); |
| 139 | Thread t = new Thread(new CheckedRunnable() { |
| 140 | public void realRun() { |
| 141 | while (!a.compareAndSet(0, 2, 3)) |
| 142 | Thread.yield(); |
| 143 | }}); |
| 144 | |
| 145 | t.start(); |
| 146 | assertTrue(a.compareAndSet(0, 1, 2)); |
| 147 | t.join(LONG_DELAY_MS); |
| 148 | assertFalse(t.isAlive()); |
| 149 | assertEquals(3, a.get(0)); |
| 150 | } |
| 151 | |
| 152 | /** |
| 153 | * repeated weakCompareAndSet succeeds in changing value when equal |
| 154 | * to expected |
| 155 | */ |
| 156 | public void testWeakCompareAndSet() { |
| 157 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 158 | for (int i = 0; i < SIZE; i++) { |
| 159 | aa.set(i, 1); |
| 160 | while (!aa.weakCompareAndSet(i, 1, 2)); |
| 161 | while (!aa.weakCompareAndSet(i, 2, -4)); |
| 162 | assertEquals(-4, aa.get(i)); |
| 163 | while (!aa.weakCompareAndSet(i, -4, 7)); |
| 164 | assertEquals(7, aa.get(i)); |
| 165 | } |
| 166 | } |
| 167 | |
| 168 | /** |
| 169 | * getAndSet returns previous value and sets to given value at given index |
| 170 | */ |
| 171 | public void testGetAndSet() { |
| 172 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 173 | for (int i = 0; i < SIZE; i++) { |
| 174 | aa.set(i, 1); |
| 175 | assertEquals(1, aa.getAndSet(i, 0)); |
| 176 | assertEquals(0, aa.getAndSet(i, -10)); |
| 177 | assertEquals(-10, aa.getAndSet(i, 1)); |
| 178 | } |
| 179 | } |
| 180 | |
| 181 | /** |
| 182 | * getAndAdd returns previous value and adds given value |
| 183 | */ |
| 184 | public void testGetAndAdd() { |
| 185 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 186 | for (int i = 0; i < SIZE; i++) { |
| 187 | aa.set(i, 1); |
| 188 | assertEquals(1, aa.getAndAdd(i, 2)); |
| 189 | assertEquals(3, aa.get(i)); |
| 190 | assertEquals(3, aa.getAndAdd(i, -4)); |
| 191 | assertEquals(-1, aa.get(i)); |
| 192 | } |
| 193 | } |
| 194 | |
| 195 | /** |
| 196 | * getAndDecrement returns previous value and decrements |
| 197 | */ |
| 198 | public void testGetAndDecrement() { |
| 199 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 200 | for (int i = 0; i < SIZE; i++) { |
| 201 | aa.set(i, 1); |
| 202 | assertEquals(1, aa.getAndDecrement(i)); |
| 203 | assertEquals(0, aa.getAndDecrement(i)); |
| 204 | assertEquals(-1, aa.getAndDecrement(i)); |
| 205 | } |
| 206 | } |
| 207 | |
| 208 | /** |
| 209 | * getAndIncrement returns previous value and increments |
| 210 | */ |
| 211 | public void testGetAndIncrement() { |
| 212 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 213 | for (int i = 0; i < SIZE; i++) { |
| 214 | aa.set(i, 1); |
| 215 | assertEquals(1, aa.getAndIncrement(i)); |
| 216 | assertEquals(2, aa.get(i)); |
| 217 | aa.set(i, -2); |
| 218 | assertEquals(-2, aa.getAndIncrement(i)); |
| 219 | assertEquals(-1, aa.getAndIncrement(i)); |
| 220 | assertEquals(0, aa.getAndIncrement(i)); |
| 221 | assertEquals(1, aa.get(i)); |
| 222 | } |
| 223 | } |
| 224 | |
| 225 | /** |
| 226 | * addAndGet adds given value to current, and returns current value |
| 227 | */ |
| 228 | public void testAddAndGet() { |
| 229 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 230 | for (int i = 0; i < SIZE; i++) { |
| 231 | aa.set(i, 1); |
| 232 | assertEquals(3, aa.addAndGet(i, 2)); |
| 233 | assertEquals(3, aa.get(i)); |
| 234 | assertEquals(-1, aa.addAndGet(i, -4)); |
| 235 | assertEquals(-1, aa.get(i)); |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | /** |
| 240 | * decrementAndGet decrements and returns current value |
| 241 | */ |
| 242 | public void testDecrementAndGet() { |
| 243 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 244 | for (int i = 0; i < SIZE; i++) { |
| 245 | aa.set(i, 1); |
| 246 | assertEquals(0, aa.decrementAndGet(i)); |
| 247 | assertEquals(-1, aa.decrementAndGet(i)); |
| 248 | assertEquals(-2, aa.decrementAndGet(i)); |
| 249 | assertEquals(-2, aa.get(i)); |
| 250 | } |
| 251 | } |
| 252 | |
| 253 | /** |
| 254 | * incrementAndGet increments and returns current value |
| 255 | */ |
| 256 | public void testIncrementAndGet() { |
| 257 | AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 258 | for (int i = 0; i < SIZE; i++) { |
| 259 | aa.set(i, 1); |
| 260 | assertEquals(2, aa.incrementAndGet(i)); |
| 261 | assertEquals(2, aa.get(i)); |
| 262 | aa.set(i, -2); |
| 263 | assertEquals(-1, aa.incrementAndGet(i)); |
| 264 | assertEquals(0, aa.incrementAndGet(i)); |
| 265 | assertEquals(1, aa.incrementAndGet(i)); |
| 266 | assertEquals(1, aa.get(i)); |
| 267 | } |
| 268 | } |
| 269 | |
| 270 | static final long COUNTDOWN = 100000; |
| 271 | |
| 272 | class Counter extends CheckedRunnable { |
| 273 | final AtomicLongArray aa; |
| 274 | volatile long counts; |
| 275 | Counter(AtomicLongArray a) { aa = a; } |
| 276 | public void realRun() { |
| 277 | for (;;) { |
| 278 | boolean done = true; |
| 279 | for (int i = 0; i < aa.length(); i++) { |
| 280 | long v = aa.get(i); |
| 281 | assertTrue(v >= 0); |
| 282 | if (v != 0) { |
| 283 | done = false; |
| 284 | if (aa.compareAndSet(i, v, v-1)) |
| 285 | ++counts; |
| 286 | } |
| 287 | } |
| 288 | if (done) |
| 289 | break; |
| 290 | } |
| 291 | } |
| 292 | } |
| 293 | |
| 294 | /** |
| 295 | * Multiple threads using same array of counters successfully |
| 296 | * update a number of times equal to total count |
| 297 | */ |
| 298 | public void testCountingInMultipleThreads() throws InterruptedException { |
| 299 | final AtomicLongArray aa = new AtomicLongArray(SIZE); |
| 300 | for (int i = 0; i < SIZE; i++) |
| 301 | aa.set(i, COUNTDOWN); |
| 302 | Counter c1 = new Counter(aa); |
| 303 | Counter c2 = new Counter(aa); |
| 304 | Thread t1 = new Thread(c1); |
| 305 | Thread t2 = new Thread(c2); |
| 306 | t1.start(); |
| 307 | t2.start(); |
| 308 | t1.join(); |
| 309 | t2.join(); |
| 310 | assertEquals(c1.counts+c2.counts, SIZE * COUNTDOWN); |
| 311 | } |
| 312 | |
| 313 | /** |
| 314 | * a deserialized serialized array holds same values |
| 315 | */ |
| 316 | public void testSerialization() throws Exception { |
| 317 | AtomicLongArray x = new AtomicLongArray(SIZE); |
| 318 | for (int i = 0; i < SIZE; i++) |
| 319 | x.set(i, -i); |
| 320 | AtomicLongArray y = serialClone(x); |
| 321 | assertNotSame(x, y); |
| 322 | assertEquals(x.length(), y.length()); |
| 323 | for (int i = 0; i < SIZE; i++) { |
| 324 | assertEquals(x.get(i), y.get(i)); |
| 325 | } |
| 326 | } |
| 327 | |
| 328 | /** |
| 329 | * toString returns current value. |
| 330 | */ |
| 331 | public void testToString() { |
| 332 | long[] a = { 17, 3, -42, 99, -7 }; |
| 333 | AtomicLongArray aa = new AtomicLongArray(a); |
| 334 | assertEquals(Arrays.toString(a), aa.toString()); |
| 335 | } |
| 336 | |
| 337 | } |