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.AtomicMarkableReference; 12 13 import junit.framework.Test; 14 import junit.framework.TestSuite; 15 16 public class AtomicMarkableReferenceTest 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(AtomicMarkableReferenceTest.class); 25 // } 26 27 /** 28 * constructor initializes to given reference and mark 29 */ 30 public void testConstructor() { 31 AtomicMarkableReference ai = new AtomicMarkableReference(one, false); 32 assertSame(one, ai.getReference()); 33 assertFalse(ai.isMarked()); 34 AtomicMarkableReference a2 = new AtomicMarkableReference(null, true); 35 assertNull(a2.getReference()); 36 assertTrue(a2.isMarked()); 37 } 38 39 /** 40 * get returns the last values of reference and mark set 41 */ 42 public void testGetSet() { 43 boolean[] mark = new boolean[1]; 44 AtomicMarkableReference ai = new AtomicMarkableReference(one, false); 45 assertSame(one, ai.getReference()); 46 assertFalse(ai.isMarked()); 47 assertSame(one, ai.get(mark)); 48 assertFalse(mark[0]); 49 ai.set(two, false); 50 assertSame(two, ai.getReference()); 51 assertFalse(ai.isMarked()); 52 assertSame(two, ai.get(mark)); 53 assertFalse(mark[0]); 54 ai.set(one, true); 55 assertSame(one, ai.getReference()); 56 assertTrue(ai.isMarked()); 57 assertSame(one, ai.get(mark)); 58 assertTrue(mark[0]); 59 } 60 61 /** 62 * attemptMark succeeds in single thread 63 */ 64 public void testAttemptMark() { 65 boolean[] mark = new boolean[1]; 66 AtomicMarkableReference ai = new AtomicMarkableReference(one, false); 67 assertFalse(ai.isMarked()); 68 assertTrue(ai.attemptMark(one, true)); 69 assertTrue(ai.isMarked()); 70 assertSame(one, ai.get(mark)); 71 assertTrue(mark[0]); 72 } 73 74 /** 75 * compareAndSet succeeds in changing values if equal to expected reference 76 * and mark else fails 77 */ 78 public void testCompareAndSet() { 79 boolean[] mark = new boolean[1]; 80 AtomicMarkableReference ai = new AtomicMarkableReference(one, false); 81 assertSame(one, ai.get(mark)); 82 assertFalse(ai.isMarked()); 83 assertFalse(mark[0]); 84 85 assertTrue(ai.compareAndSet(one, two, false, false)); 86 assertSame(two, ai.get(mark)); 87 assertFalse(mark[0]); 88 89 assertTrue(ai.compareAndSet(two, m3, false, true)); 90 assertSame(m3, ai.get(mark)); 91 assertTrue(mark[0]); 92 93 assertFalse(ai.compareAndSet(two, m3, true, true)); 94 assertSame(m3, ai.get(mark)); 95 assertTrue(mark[0]); 96 } 97 98 /** 99 * compareAndSet in one thread enables another waiting for reference value 100 * to succeed 101 */ 102 public void testCompareAndSetInMultipleThreads() throws Exception { 103 final AtomicMarkableReference ai = new AtomicMarkableReference(one, false); 104 Thread t = new Thread(new CheckedRunnable() { 105 public void realRun() { 106 while (!ai.compareAndSet(two, three, false, false)) 107 Thread.yield(); 108 }}); 109 110 t.start(); 111 assertTrue(ai.compareAndSet(one, two, false, false)); 112 t.join(LONG_DELAY_MS); 113 assertFalse(t.isAlive()); 114 assertSame(three, ai.getReference()); 115 assertFalse(ai.isMarked()); 116 } 117 118 /** 119 * compareAndSet in one thread enables another waiting for mark value 120 * to succeed 121 */ 122 public void testCompareAndSetInMultipleThreads2() throws Exception { 123 final AtomicMarkableReference ai = new AtomicMarkableReference(one, false); 124 Thread t = new Thread(new CheckedRunnable() { 125 public void realRun() { 126 while (!ai.compareAndSet(one, one, true, false)) 127 Thread.yield(); 128 }}); 129 130 t.start(); 131 assertTrue(ai.compareAndSet(one, one, false, true)); 132 t.join(LONG_DELAY_MS); 133 assertFalse(t.isAlive()); 134 assertSame(one, ai.getReference()); 135 assertFalse(ai.isMarked()); 136 } 137 138 /** 139 * repeated weakCompareAndSet succeeds in changing values when equal 140 * to expected 141 */ 142 public void testWeakCompareAndSet() { 143 boolean[] mark = new boolean[1]; 144 AtomicMarkableReference ai = new AtomicMarkableReference(one, false); 145 assertSame(one, ai.get(mark)); 146 assertFalse(ai.isMarked()); 147 assertFalse(mark[0]); 148 149 do {} while (!ai.weakCompareAndSet(one, two, false, false)); 150 assertSame(two, ai.get(mark)); 151 assertFalse(mark[0]); 152 153 do {} while (!ai.weakCompareAndSet(two, m3, false, true)); 154 assertSame(m3, ai.get(mark)); 155 assertTrue(mark[0]); 156 } 157 158 } 159
