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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.concurrent.atomic.AtomicInteger; |
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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 AtomicIntegerTest 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(AtomicIntegerTest.class); |
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} |
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|
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final int[] VALUES = { |
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Integer.MIN_VALUE, -1, 0, 1, 42, Integer.MAX_VALUE, |
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}; |
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|
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/** |
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* constructor initializes to given value |
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*/ |
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public void testConstructor() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(1, ai.get()); |
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} |
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|
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/** |
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* default constructed initializes to zero |
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*/ |
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public void testConstructor2() { |
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AtomicInteger ai = new AtomicInteger(); |
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assertEquals(0, ai.get()); |
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} |
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|
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/** |
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* get returns the last value set |
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*/ |
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public void testGetSet() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(1, ai.get()); |
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ai.set(2); |
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assertEquals(2, ai.get()); |
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ai.set(-3); |
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assertEquals(-3, ai.get()); |
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} |
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|
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/** |
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* get returns the last value lazySet in same thread |
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*/ |
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public void testGetLazySet() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(1, ai.get()); |
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ai.lazySet(2); |
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assertEquals(2, ai.get()); |
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ai.lazySet(-3); |
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assertEquals(-3, ai.get()); |
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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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AtomicInteger ai = new AtomicInteger(1); |
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assertTrue(ai.compareAndSet(1, 2)); |
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assertTrue(ai.compareAndSet(2, -4)); |
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assertEquals(-4, ai.get()); |
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assertFalse(ai.compareAndSet(-5, 7)); |
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assertEquals(-4, ai.get()); |
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assertTrue(ai.compareAndSet(-4, 7)); |
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assertEquals(7, ai.get()); |
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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 Exception { |
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final AtomicInteger ai = new AtomicInteger(1); |
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Thread t = new Thread(new CheckedRunnable() { |
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public void realRun() { |
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while (!ai.compareAndSet(2, 3)) |
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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(ai.compareAndSet(1, 2)); |
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t.join(LONG_DELAY_MS); |
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assertFalse(t.isAlive()); |
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assertEquals(3, ai.get()); |
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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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@SuppressWarnings("deprecation") |
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public void testWeakCompareAndSet() { |
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AtomicInteger ai = new AtomicInteger(1); |
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do {} while (!ai.weakCompareAndSet(1, 2)); |
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do {} while (!ai.weakCompareAndSet(2, -4)); |
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assertEquals(-4, ai.get()); |
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do {} while (!ai.weakCompareAndSet(-4, 7)); |
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assertEquals(7, ai.get()); |
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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 |
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*/ |
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public void testGetAndSet() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(1, ai.getAndSet(0)); |
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assertEquals(0, ai.getAndSet(-10)); |
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assertEquals(-10, ai.getAndSet(1)); |
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} |
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|
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/** |
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* getAndAdd returns previous value and adds given value |
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*/ |
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public void testGetAndAdd() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(1, ai.getAndAdd(2)); |
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assertEquals(3, ai.get()); |
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assertEquals(3, ai.getAndAdd(-4)); |
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assertEquals(-1, ai.get()); |
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} |
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|
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/** |
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* getAndDecrement returns previous value and decrements |
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*/ |
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public void testGetAndDecrement() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(1, ai.getAndDecrement()); |
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assertEquals(0, ai.getAndDecrement()); |
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assertEquals(-1, ai.getAndDecrement()); |
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} |
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|
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/** |
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* getAndIncrement returns previous value and increments |
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*/ |
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public void testGetAndIncrement() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(1, ai.getAndIncrement()); |
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assertEquals(2, ai.get()); |
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ai.set(-2); |
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assertEquals(-2, ai.getAndIncrement()); |
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assertEquals(-1, ai.getAndIncrement()); |
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assertEquals(0, ai.getAndIncrement()); |
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assertEquals(1, ai.get()); |
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} |
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|
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/** |
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* addAndGet adds given value to current, and returns current value |
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*/ |
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public void testAddAndGet() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(3, ai.addAndGet(2)); |
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assertEquals(3, ai.get()); |
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assertEquals(-1, ai.addAndGet(-4)); |
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assertEquals(-1, ai.get()); |
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} |
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|
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/** |
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* decrementAndGet decrements and returns current value |
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*/ |
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public void testDecrementAndGet() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(0, ai.decrementAndGet()); |
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assertEquals(-1, ai.decrementAndGet()); |
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assertEquals(-2, ai.decrementAndGet()); |
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assertEquals(-2, ai.get()); |
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} |
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|
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/** |
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* incrementAndGet increments and returns current value |
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*/ |
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public void testIncrementAndGet() { |
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AtomicInteger ai = new AtomicInteger(1); |
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assertEquals(2, ai.incrementAndGet()); |
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assertEquals(2, ai.get()); |
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ai.set(-2); |
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assertEquals(-1, ai.incrementAndGet()); |
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assertEquals(0, ai.incrementAndGet()); |
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assertEquals(1, ai.incrementAndGet()); |
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assertEquals(1, ai.get()); |
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} |
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|
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/** |
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* a deserialized/reserialized atomic holds same value |
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*/ |
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public void testSerialization() throws Exception { |
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AtomicInteger x = new AtomicInteger(); |
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AtomicInteger y = serialClone(x); |
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assertNotSame(x, y); |
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x.set(22); |
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AtomicInteger z = serialClone(x); |
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assertEquals(22, x.get()); |
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assertEquals(0, y.get()); |
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assertEquals(22, z.get()); |
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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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AtomicInteger ai = new AtomicInteger(); |
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assertEquals("0", ai.toString()); |
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for (int x : VALUES) { |
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ai.set(x); |
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assertEquals(Integer.toString(x), ai.toString()); |
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} |
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} |
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|
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/** |
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* intValue returns current value. |
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*/ |
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public void testIntValue() { |
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AtomicInteger ai = new AtomicInteger(); |
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assertEquals(0, ai.intValue()); |
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for (int x : VALUES) { |
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ai.set(x); |
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assertEquals(x, ai.intValue()); |
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} |
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} |
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|
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/** |
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* longValue returns current value. |
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*/ |
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public void testLongValue() { |
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AtomicInteger ai = new AtomicInteger(); |
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assertEquals(0L, ai.longValue()); |
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for (int x : VALUES) { |
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ai.set(x); |
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assertEquals((long)x, ai.longValue()); |
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} |
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} |
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|
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/** |
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* floatValue returns current value. |
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*/ |
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public void testFloatValue() { |
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AtomicInteger ai = new AtomicInteger(); |
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assertEquals(0.0f, ai.floatValue()); |
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for (int x : VALUES) { |
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ai.set(x); |
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assertEquals((float)x, ai.floatValue()); |
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} |
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} |
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|
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/** |
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* doubleValue returns current value. |
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*/ |
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public void testDoubleValue() { |
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AtomicInteger ai = new AtomicInteger(); |
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assertEquals(0.0d, ai.doubleValue()); |
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for (int x : VALUES) { |
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ai.set(x); |
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assertEquals((double)x, ai.doubleValue()); |
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} |
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} |
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|
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} |