AtomicBooleanTest.java revision 8f0d92bba199d906c70a5e40d7f3516c1a424117
18f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle/* 28f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * Written by Doug Lea with assistance from members of JCP JSR-166 38f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * Expert Group and released to the public domain, as explained at 48f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * http://creativecommons.org/publicdomain/zero/1.0/ 58f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * Other contributors include Andrew Wright, Jeffrey Hayes, 68f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * Pat Fisher, Mike Judd. 78f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 88f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 98f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravlepackage jsr166; 108f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 118f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravleimport junit.framework.*; 128f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravleimport java.util.concurrent.atomic.AtomicBoolean; 138f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 148f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravlepublic class AtomicBooleanTest extends JSR166TestCase { 158f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 168f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 178f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * constructor initializes to given value 188f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 198f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testConstructor() { 208f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(new AtomicBoolean(true).get()); 218f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(new AtomicBoolean(false).get()); 228f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 238f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 248f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 258f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * default constructed initializes to false 268f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 278f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testConstructor2() { 288f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean ai = new AtomicBoolean(); 298f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 308f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 318f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 328f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 338f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * get returns the last value set 348f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 358f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testGetSet() { 368f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean ai = new AtomicBoolean(true); 378f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.get()); 388f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle ai.set(false); 398f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 408f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle ai.set(true); 418f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.get()); 428f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 438f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 448f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 458f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * get returns the last value lazySet in same thread 468f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 478f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testGetLazySet() { 488f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean ai = new AtomicBoolean(true); 498f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.get()); 508f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle ai.lazySet(false); 518f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 528f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle ai.lazySet(true); 538f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.get()); 548f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 558f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 568f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 578f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * compareAndSet succeeds in changing value if equal to expected else fails 588f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 598f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testCompareAndSet() { 608f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean ai = new AtomicBoolean(true); 618f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.compareAndSet(true, false)); 628f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 638f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.compareAndSet(false, false)); 648f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 658f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.compareAndSet(true, false)); 668f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 678f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.compareAndSet(false, true)); 688f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.get()); 698f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 708f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 718f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 728f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * compareAndSet in one thread enables another waiting for value 738f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * to succeed 748f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 758f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testCompareAndSetInMultipleThreads() throws Exception { 768f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle final AtomicBoolean ai = new AtomicBoolean(true); 778f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle Thread t = new Thread(new CheckedRunnable() { 788f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void realRun() { 798f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle while (!ai.compareAndSet(false, true)) Thread.yield(); 808f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle }}); 818f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 828f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle t.start(); 838f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.compareAndSet(true, false)); 848f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle t.join(LONG_DELAY_MS); 858f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(t.isAlive()); 868f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 878f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 888f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 898f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * repeated weakCompareAndSet succeeds in changing value when equal 908f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * to expected 918f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 928f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testWeakCompareAndSet() { 938f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean ai = new AtomicBoolean(true); 948f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle while (!ai.weakCompareAndSet(true, false)); 958f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 968f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle while (!ai.weakCompareAndSet(false, false)); 978f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(ai.get()); 988f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle while (!ai.weakCompareAndSet(false, true)); 998f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.get()); 1008f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 1018f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 1028f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 1038f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * getAndSet returns previous value and sets to given value 1048f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 1058f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testGetAndSet() { 1068f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean ai = new AtomicBoolean(true); 1078f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertEquals(true, ai.getAndSet(false)); 1088f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertEquals(false, ai.getAndSet(false)); 1098f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertEquals(false, ai.getAndSet(true)); 1108f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(ai.get()); 1118f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 1128f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 1138f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 1148f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * a deserialized serialized atomic holds same value 1158f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 1168f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testSerialization() throws Exception { 1178f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean x = new AtomicBoolean(); 1188f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean y = serialClone(x); 1198f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle x.set(true); 1208f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean z = serialClone(x); 1218f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(x.get()); 1228f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertFalse(y.get()); 1238f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertTrue(z.get()); 1248f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 1258f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 1268f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle /** 1278f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle * toString returns current value. 1288f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle */ 1298f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle public void testToString() { 1308f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle AtomicBoolean ai = new AtomicBoolean(); 1318f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertEquals(Boolean.toString(false), ai.toString()); 1328f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle ai.set(true); 1338f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle assertEquals(Boolean.toString(true), ai.toString()); 1348f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle } 1358f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle 1368f0d92bba199d906c70a5e40d7f3516c1a424117Calin Juravle} 137