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/* |
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* 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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* Other contributors include Andrew Wright, Jeffrey Hayes, |
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* Pat Fisher, Mike Judd. |
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*/ |
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|
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import junit.framework.*; |
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import java.util.concurrent.atomic.*; |
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import java.io.*; |
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|
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public class AtomicReferenceArrayTest extends JSR166TestCase |
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{ |
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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(AtomicReferenceArrayTest.class); |
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} |
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|
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/** |
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* constructor creates array of given size with all elements null |
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*/ |
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public void testConstructor(){ |
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AtomicReferenceArray<Integer> ai = new AtomicReferenceArray<Integer>(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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assertNull(ai.get(i)); |
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} |
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} |
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|
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/** |
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* get and set for out of bound indices throw IndexOutOfBoundsException |
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*/ |
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public void testIndexing(){ |
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AtomicReferenceArray<Integer> ai = new AtomicReferenceArray<Integer>(SIZE); |
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try { |
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ai.get(SIZE); |
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} catch(IndexOutOfBoundsException success){ |
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} |
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try { |
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ai.get(-1); |
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} catch(IndexOutOfBoundsException success){ |
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} |
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try { |
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ai.set(SIZE, null); |
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} catch(IndexOutOfBoundsException success){ |
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} |
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try { |
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ai.set(-1, null); |
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} catch(IndexOutOfBoundsException success){ |
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} |
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} |
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|
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/** |
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* get returns the last value set at index |
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*/ |
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public void testGetSet(){ |
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AtomicReferenceArray ai = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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ai.set(i, one); |
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assertEquals(one,ai.get(i)); |
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ai.set(i, two); |
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assertEquals(two,ai.get(i)); |
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ai.set(i, m3); |
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assertEquals(m3,ai.get(i)); |
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} |
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} |
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|
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/** |
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* compareAndSet succeeds in changing value if equal to expected else fails |
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*/ |
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public void testCompareAndSet(){ |
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AtomicReferenceArray ai = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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ai.set(i, one); |
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assertTrue(ai.compareAndSet(i, one,two)); |
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assertTrue(ai.compareAndSet(i, two,m4)); |
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assertEquals(m4,ai.get(i)); |
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assertFalse(ai.compareAndSet(i, m5,seven)); |
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assertFalse((seven.equals(ai.get(i)))); |
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assertTrue(ai.compareAndSet(i, m4,seven)); |
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assertEquals(seven,ai.get(i)); |
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} |
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} |
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|
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/** |
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* compareAndSet in one thread enables another waiting for value |
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* to succeed |
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*/ |
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public void testCompareAndSetInMultipleThreads() { |
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final AtomicReferenceArray a = new AtomicReferenceArray(1); |
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a.set(0, one); |
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Thread t = new Thread(new Runnable() { |
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public void run() { |
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while(!a.compareAndSet(0, two, three)) Thread.yield(); |
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}}); |
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try { |
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t.start(); |
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assertTrue(a.compareAndSet(0, one, two)); |
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t.join(LONG_DELAY_MS); |
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assertFalse(t.isAlive()); |
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assertEquals(a.get(0), three); |
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} |
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catch(Exception e) { |
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unexpectedException(); |
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} |
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} |
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|
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/** |
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* repeated weakCompareAndSet succeeds in changing value when equal |
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* to expected |
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*/ |
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public void testWeakCompareAndSet(){ |
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AtomicReferenceArray ai = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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ai.set(i, one); |
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while(!ai.weakCompareAndSet(i, one,two)); |
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while(!ai.weakCompareAndSet(i, two,m4)); |
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assertEquals(m4,ai.get(i)); |
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while(!ai.weakCompareAndSet(i, m4,seven)); |
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assertEquals(seven,ai.get(i)); |
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} |
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} |
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|
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/** |
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* getAndSet returns previous value and sets to given value at given index |
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*/ |
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public void testGetAndSet(){ |
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AtomicReferenceArray ai = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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ai.set(i, one); |
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assertEquals(one,ai.getAndSet(i,zero)); |
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assertEquals(0,ai.getAndSet(i,m10)); |
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assertEquals(m10,ai.getAndSet(i,one)); |
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} |
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} |
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|
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/** |
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* a deserialized serialized array holds same values |
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*/ |
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public void testSerialization() { |
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AtomicReferenceArray l = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; ++i) { |
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l.set(i, new Integer(-i)); |
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} |
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|
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try { |
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ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); |
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ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); |
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out.writeObject(l); |
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out.close(); |
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|
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ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); |
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ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); |
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AtomicReferenceArray r = (AtomicReferenceArray) in.readObject(); |
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assertEquals(l.length(), r.length()); |
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for (int i = 0; i < SIZE; ++i) { |
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assertEquals(r.get(i), l.get(i)); |
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} |
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} catch(Exception e){ |
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unexpectedException(); |
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} |
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} |
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|
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} |
