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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 junit.framework.*; |
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import java.util.concurrent.atomic.AtomicLongFieldUpdater; |
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|
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public class AtomicLongFieldUpdaterTest extends JSR166TestCase { |
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volatile long x = 0; |
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int z; |
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long w; |
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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(AtomicLongFieldUpdaterTest.class); |
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} |
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|
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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> updaterFor(String fieldName) { |
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return AtomicLongFieldUpdater.newUpdater |
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(AtomicLongFieldUpdaterTest.class, fieldName); |
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} |
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|
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/** |
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* Construction with non-existent field throws RuntimeException |
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*/ |
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public void testConstructor() { |
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try { |
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updaterFor("y"); |
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shouldThrow(); |
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} catch (RuntimeException success) {} |
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} |
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|
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/** |
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* construction with field not of given type throws RuntimeException |
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*/ |
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public void testConstructor2() { |
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try { |
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updaterFor("z"); |
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shouldThrow(); |
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} catch (RuntimeException success) {} |
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} |
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|
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/** |
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* construction with non-volatile field throws RuntimeException |
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*/ |
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public void testConstructor3() { |
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try { |
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updaterFor("w"); |
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shouldThrow(); |
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} catch (RuntimeException success) {} |
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} |
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|
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/** |
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* get returns the last value set or assigned |
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*/ |
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public void testGetSet() { |
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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(1, a.get(this)); |
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a.set(this, 2); |
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assertEquals(2, a.get(this)); |
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a.set(this, -3); |
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assertEquals(-3, a.get(this)); |
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} |
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|
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/** |
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* get returns the last value lazySet by same thread |
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*/ |
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public void testGetLazySet() { |
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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(1, a.get(this)); |
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a.lazySet(this, 2); |
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assertEquals(2, a.get(this)); |
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a.lazySet(this, -3); |
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assertEquals(-3, a.get(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertTrue(a.compareAndSet(this, 1, 2)); |
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assertTrue(a.compareAndSet(this, 2, -4)); |
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assertEquals(-4, a.get(this)); |
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assertFalse(a.compareAndSet(this, -5, 7)); |
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assertEquals(-4, a.get(this)); |
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assertTrue(a.compareAndSet(this, -4, 7)); |
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assertEquals(7, a.get(this)); |
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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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x = 1; |
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final AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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|
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Thread t = new Thread(new CheckedRunnable() { |
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public void realRun() { |
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while (!a.compareAndSet(AtomicLongFieldUpdaterTest.this, 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(a.compareAndSet(this, 1, 2)); |
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t.join(LONG_DELAY_MS); |
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assertFalse(t.isAlive()); |
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assertEquals(3, a.get(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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while (!a.weakCompareAndSet(this, 1, 2)); |
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while (!a.weakCompareAndSet(this, 2, -4)); |
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assertEquals(-4, a.get(this)); |
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while (!a.weakCompareAndSet(this, -4, 7)); |
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assertEquals(7, a.get(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(1, a.getAndSet(this, 0)); |
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assertEquals(0, a.getAndSet(this, -10)); |
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assertEquals(-10, a.getAndSet(this, 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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(1, a.getAndAdd(this, 2)); |
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assertEquals(3, a.get(this)); |
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assertEquals(3, a.getAndAdd(this, -4)); |
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assertEquals(-1, a.get(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(1, a.getAndDecrement(this)); |
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assertEquals(0, a.getAndDecrement(this)); |
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assertEquals(-1, a.getAndDecrement(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(1, a.getAndIncrement(this)); |
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assertEquals(2, a.get(this)); |
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a.set(this, -2); |
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assertEquals(-2, a.getAndIncrement(this)); |
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assertEquals(-1, a.getAndIncrement(this)); |
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assertEquals(0, a.getAndIncrement(this)); |
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assertEquals(1, a.get(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(3, a.addAndGet(this, 2)); |
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assertEquals(3, a.get(this)); |
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assertEquals(-1, a.addAndGet(this, -4)); |
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assertEquals(-1, a.get(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(0, a.decrementAndGet(this)); |
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assertEquals(-1, a.decrementAndGet(this)); |
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assertEquals(-2, a.decrementAndGet(this)); |
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assertEquals(-2, a.get(this)); |
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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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AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; |
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a = updaterFor("x"); |
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x = 1; |
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assertEquals(2, a.incrementAndGet(this)); |
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assertEquals(2, a.get(this)); |
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a.set(this, -2); |
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assertEquals(-1, a.incrementAndGet(this)); |
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assertEquals(0, a.incrementAndGet(this)); |
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assertEquals(1, a.incrementAndGet(this)); |
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assertEquals(1, a.get(this)); |
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} |
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|
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} |
