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dl |
1.1 |
/* |
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dl |
1.5 |
* Written by Doug Lea with assistance from members of JCP JSR-166 |
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* Expert Group and released to the public domain, as explained at |
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* http://creativecommons.org/licenses/publicdomain |
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jsr166 |
1.8 |
* Other contributors include Andrew Wright, Jeffrey Hayes, |
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* Pat Fisher, Mike Judd. |
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dl |
1.5 |
*/ |
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dl |
1.1 |
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import junit.framework.*; |
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import java.util.concurrent.atomic.*; |
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jsr166 |
1.10 |
public class AtomicStampedReferenceTest extends JSR166TestCase { |
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dl |
1.1 |
public static void main (String[] args) { |
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junit.textui.TestRunner.run (suite()); |
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} |
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public static Test suite() { |
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return new TestSuite(AtomicStampedReferenceTest.class); |
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} |
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jsr166 |
1.8 |
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dl |
1.3 |
/** |
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dl |
1.7 |
* constructor initializes to given reference and stamp |
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dl |
1.3 |
*/ |
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jsr166 |
1.10 |
public void testConstructor() { |
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dl |
1.1 |
AtomicStampedReference ai = new AtomicStampedReference(one, 0); |
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assertEquals(one,ai.getReference()); |
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assertEquals(0, ai.getStamp()); |
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AtomicStampedReference a2 = new AtomicStampedReference(null, 1); |
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assertNull(a2.getReference()); |
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assertEquals(1, a2.getStamp()); |
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} |
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dl |
1.3 |
/** |
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1.4 |
* get returns the last values of reference and stamp set |
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dl |
1.3 |
*/ |
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jsr166 |
1.10 |
public void testGetSet() { |
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dl |
1.1 |
int[] mark = new int[1]; |
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AtomicStampedReference ai = new AtomicStampedReference(one, 0); |
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assertEquals(one,ai.getReference()); |
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assertEquals(0, ai.getStamp()); |
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assertEquals(one, ai.get(mark)); |
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assertEquals(0, mark[0]); |
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ai.set(two, 0); |
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assertEquals(two,ai.getReference()); |
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assertEquals(0, ai.getStamp()); |
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assertEquals(two, ai.get(mark)); |
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assertEquals(0, mark[0]); |
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ai.set(one, 1); |
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assertEquals(one,ai.getReference()); |
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assertEquals(1, ai.getStamp()); |
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assertEquals(one, ai.get(mark)); |
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assertEquals(1,mark[0]); |
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} |
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dl |
1.3 |
/** |
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dl |
1.4 |
* attemptStamp succeeds in single thread |
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dl |
1.3 |
*/ |
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jsr166 |
1.10 |
public void testAttemptStamp() { |
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dl |
1.1 |
int[] mark = new int[1]; |
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AtomicStampedReference ai = new AtomicStampedReference(one, 0); |
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assertEquals(0, ai.getStamp()); |
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assertTrue(ai.attemptStamp(one, 1)); |
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assertEquals(1, ai.getStamp()); |
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assertEquals(one, ai.get(mark)); |
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assertEquals(1, mark[0]); |
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} |
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dl |
1.3 |
/** |
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1.4 |
* compareAndSet succeeds in changing values if equal to expected reference |
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* and stamp else fails |
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dl |
1.3 |
*/ |
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jsr166 |
1.10 |
public void testCompareAndSet() { |
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dl |
1.1 |
int[] mark = new int[1]; |
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AtomicStampedReference ai = new AtomicStampedReference(one, 0); |
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assertEquals(one, ai.get(mark)); |
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assertEquals(0, ai.getStamp()); |
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assertEquals(0, mark[0]); |
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assertTrue(ai.compareAndSet(one, two, 0, 0)); |
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assertEquals(two, ai.get(mark)); |
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assertEquals(0, mark[0]); |
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assertTrue(ai.compareAndSet(two, m3, 0, 1)); |
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assertEquals(m3, ai.get(mark)); |
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assertEquals(1, mark[0]); |
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assertFalse(ai.compareAndSet(two, m3, 1, 1)); |
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assertEquals(m3, ai.get(mark)); |
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assertEquals(1, mark[0]); |
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} |
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1.3 |
/** |
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1.4 |
* compareAndSet in one thread enables another waiting for reference value |
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* to succeed |
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*/ |
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public void testCompareAndSetInMultipleThreads() { |
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final AtomicStampedReference ai = new AtomicStampedReference(one, 0); |
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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jsr166 |
1.9 |
while (!ai.compareAndSet(two, three, 0, 0)) Thread.yield(); |
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1.4 |
}}); |
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try { |
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t.start(); |
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assertTrue(ai.compareAndSet(one, two, 0, 0)); |
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t.join(LONG_DELAY_MS); |
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assertFalse(t.isAlive()); |
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assertEquals(ai.getReference(), three); |
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assertEquals(ai.getStamp(), 0); |
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} |
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jsr166 |
1.9 |
catch (Exception e) { |
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dl |
1.4 |
unexpectedException(); |
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} |
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} |
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/** |
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* compareAndSet in one thread enables another waiting for stamp value |
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* to succeed |
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*/ |
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public void testCompareAndSetInMultipleThreads2() { |
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final AtomicStampedReference ai = new AtomicStampedReference(one, 0); |
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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jsr166 |
1.9 |
while (!ai.compareAndSet(one, one, 1, 2)) Thread.yield(); |
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dl |
1.4 |
}}); |
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try { |
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t.start(); |
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assertTrue(ai.compareAndSet(one, one, 0, 1)); |
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t.join(LONG_DELAY_MS); |
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assertFalse(t.isAlive()); |
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assertEquals(ai.getReference(), one); |
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assertEquals(ai.getStamp(), 2); |
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} |
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jsr166 |
1.9 |
catch (Exception e) { |
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dl |
1.4 |
unexpectedException(); |
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} |
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} |
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/** |
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* repeated weakCompareAndSet succeeds in changing values when equal |
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jsr166 |
1.8 |
* to expected |
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dl |
1.3 |
*/ |
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jsr166 |
1.10 |
public void testWeakCompareAndSet() { |
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dl |
1.1 |
int[] mark = new int[1]; |
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AtomicStampedReference ai = new AtomicStampedReference(one, 0); |
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assertEquals(one, ai.get(mark)); |
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assertEquals(0, ai.getStamp ()); |
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assertEquals(0, mark[0]); |
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jsr166 |
1.9 |
while (!ai.weakCompareAndSet(one, two, 0, 0)); |
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dl |
1.1 |
assertEquals(two, ai.get(mark)); |
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assertEquals(0, mark[0]); |
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153 |
jsr166 |
1.9 |
while (!ai.weakCompareAndSet(two, m3, 0, 1)); |
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dl |
1.1 |
assertEquals(m3, ai.get(mark)); |
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assertEquals(1, mark[0]); |
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} |
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} |