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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/publicdomain/zero/1.0/ |
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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 java.util.Arrays; |
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import java.util.concurrent.atomic.AtomicReferenceArray; |
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|
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import junit.framework.Test; |
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import junit.framework.TestSuite; |
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|
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public class AtomicReferenceArrayTest extends JSR166TestCase { |
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public static void main(String[] args) { |
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main(suite(), args); |
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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> aa = new AtomicReferenceArray<Integer>(SIZE); |
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for (int i = 0; i < SIZE; i++) { |
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assertNull(aa.get(i)); |
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} |
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} |
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|
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/** |
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* constructor with null array throws NPE |
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*/ |
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public void testConstructor2NPE() { |
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try { |
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Integer[] a = null; |
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new AtomicReferenceArray<Integer>(a); |
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shouldThrow(); |
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} catch (NullPointerException success) {} |
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} |
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|
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/** |
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* constructor with array is of same size and has all elements |
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*/ |
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public void testConstructor2() { |
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Integer[] a = { two, one, three, four, seven }; |
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AtomicReferenceArray<Integer> aa = new AtomicReferenceArray<Integer>(a); |
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assertEquals(a.length, aa.length()); |
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for (int i = 0; i < a.length; i++) |
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assertEquals(a[i], aa.get(i)); |
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} |
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|
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/** |
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* Initialize AtomicReferenceArray<Class> with SubClass[] |
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*/ |
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public void testConstructorSubClassArray() { |
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Integer[] a = { two, one, three, four, seven }; |
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AtomicReferenceArray<Number> aa = new AtomicReferenceArray<Number>(a); |
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assertEquals(a.length, aa.length()); |
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for (int i = 0; i < a.length; i++) { |
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assertSame(a[i], aa.get(i)); |
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Long x = Long.valueOf(i); |
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aa.set(i, x); |
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assertSame(x, aa.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> aa = new AtomicReferenceArray<Integer>(SIZE); |
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for (int index : new int[] { -1, SIZE }) { |
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try { |
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aa.get(index); |
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shouldThrow(); |
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} catch (IndexOutOfBoundsException success) {} |
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try { |
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aa.set(index, null); |
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shouldThrow(); |
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} catch (IndexOutOfBoundsException success) {} |
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try { |
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aa.lazySet(index, null); |
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shouldThrow(); |
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} catch (IndexOutOfBoundsException success) {} |
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try { |
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aa.compareAndSet(index, null, null); |
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shouldThrow(); |
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} catch (IndexOutOfBoundsException success) {} |
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try { |
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aa.weakCompareAndSet(index, null, null); |
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shouldThrow(); |
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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 aa = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; i++) { |
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aa.set(i, one); |
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assertSame(one, aa.get(i)); |
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aa.set(i, two); |
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assertSame(two, aa.get(i)); |
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aa.set(i, m3); |
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assertSame(m3, aa.get(i)); |
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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 lazySet at index by same thread |
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*/ |
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public void testGetLazySet() { |
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AtomicReferenceArray aa = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; i++) { |
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aa.lazySet(i, one); |
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assertSame(one, aa.get(i)); |
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aa.lazySet(i, two); |
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assertSame(two, aa.get(i)); |
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aa.lazySet(i, m3); |
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assertSame(m3, aa.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 aa = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; i++) { |
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aa.set(i, one); |
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assertTrue(aa.compareAndSet(i, one, two)); |
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assertTrue(aa.compareAndSet(i, two, m4)); |
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assertSame(m4, aa.get(i)); |
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assertFalse(aa.compareAndSet(i, m5, seven)); |
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assertSame(m4, aa.get(i)); |
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assertTrue(aa.compareAndSet(i, m4, seven)); |
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assertSame(seven, aa.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() throws InterruptedException { |
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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 CheckedRunnable() { |
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public void realRun() { |
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while (!a.compareAndSet(0, two, three)) |
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Thread.yield(); |
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}}); |
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|
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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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assertSame(three, a.get(0)); |
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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 aa = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; i++) { |
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aa.set(i, one); |
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do {} while (!aa.weakCompareAndSet(i, one, two)); |
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do {} while (!aa.weakCompareAndSet(i, two, m4)); |
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assertSame(m4, aa.get(i)); |
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do {} while (!aa.weakCompareAndSet(i, m4, seven)); |
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assertSame(seven, aa.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 aa = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; i++) { |
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aa.set(i, one); |
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assertSame(one, aa.getAndSet(i, zero)); |
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assertSame(zero, aa.getAndSet(i, m10)); |
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assertSame(m10, aa.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() throws Exception { |
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AtomicReferenceArray x = new AtomicReferenceArray(SIZE); |
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for (int i = 0; i < SIZE; i++) { |
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x.set(i, new Integer(-i)); |
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} |
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AtomicReferenceArray y = serialClone(x); |
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assertNotSame(x, y); |
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assertEquals(x.length(), y.length()); |
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for (int i = 0; i < SIZE; i++) { |
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assertEquals(x.get(i), y.get(i)); |
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} |
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} |
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|
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/** |
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* toString returns current value. |
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*/ |
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public void testToString() { |
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Integer[] a = { two, one, three, four, seven }; |
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AtomicReferenceArray<Integer> aa = new AtomicReferenceArray<Integer>(a); |
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assertEquals(Arrays.toString(a), aa.toString()); |
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} |
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} |
