/* * Written by Doug Lea with assistance from members of JCP JSR-166 * Expert Group and released to the public domain, as explained at * http://creativecommons.org/publicdomain/zero/1.0/ * Other contributors include Andrew Wright, Jeffrey Hayes, * Pat Fisher, Mike Judd. */ package jsr166; import java.util.concurrent.atomic.AtomicLongFieldUpdater; import junit.framework.Test; import junit.framework.TestSuite; public class AtomicLongFieldUpdaterTest extends JSR166TestCase { volatile long x = 0; int z; long w; // android-note: Removed because the CTS runner does a bad job of // retrying tests that have suite() declarations. // // public static void main(String[] args) { // main(suite(), args); // } // public static Test suite() { // return new TestSuite(...); // } AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> updaterFor(String fieldName) { return AtomicLongFieldUpdater.newUpdater (AtomicLongFieldUpdaterTest.class, fieldName); } /** * Construction with non-existent field throws RuntimeException */ public void testConstructor() { try { updaterFor("y"); shouldThrow(); } catch (RuntimeException success) { assertNotNull(success.getCause()); } } /** * construction with field not of given type throws IllegalArgumentException */ public void testConstructor2() { try { updaterFor("z"); shouldThrow(); } catch (IllegalArgumentException success) {} } /** * construction with non-volatile field throws IllegalArgumentException */ public void testConstructor3() { try { updaterFor("w"); shouldThrow(); } catch (IllegalArgumentException success) {} } /** * get returns the last value set or assigned */ public void testGetSet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(1, a.get(this)); a.set(this, 2); assertEquals(2, a.get(this)); a.set(this, -3); assertEquals(-3, a.get(this)); } /** * get returns the last value lazySet by same thread */ public void testGetLazySet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(1, a.get(this)); a.lazySet(this, 2); assertEquals(2, a.get(this)); a.lazySet(this, -3); assertEquals(-3, a.get(this)); } /** * compareAndSet succeeds in changing value if equal to expected else fails */ public void testCompareAndSet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertTrue(a.compareAndSet(this, 1, 2)); assertTrue(a.compareAndSet(this, 2, -4)); assertEquals(-4, a.get(this)); assertFalse(a.compareAndSet(this, -5, 7)); assertEquals(-4, a.get(this)); assertTrue(a.compareAndSet(this, -4, 7)); assertEquals(7, a.get(this)); } /** * compareAndSet in one thread enables another waiting for value * to succeed */ public void testCompareAndSetInMultipleThreads() throws Exception { x = 1; final AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); Thread t = new Thread(new CheckedRunnable() { public void realRun() { while (!a.compareAndSet(AtomicLongFieldUpdaterTest.this, 2, 3)) Thread.yield(); }}); t.start(); assertTrue(a.compareAndSet(this, 1, 2)); t.join(LONG_DELAY_MS); assertFalse(t.isAlive()); assertEquals(3, a.get(this)); } /** * repeated weakCompareAndSet succeeds in changing value when equal * to expected */ public void testWeakCompareAndSet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; do {} while (!a.weakCompareAndSet(this, 1, 2)); do {} while (!a.weakCompareAndSet(this, 2, -4)); assertEquals(-4, a.get(this)); do {} while (!a.weakCompareAndSet(this, -4, 7)); assertEquals(7, a.get(this)); } /** * getAndSet returns previous value and sets to given value */ public void testGetAndSet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(1, a.getAndSet(this, 0)); assertEquals(0, a.getAndSet(this, -10)); assertEquals(-10, a.getAndSet(this, 1)); } /** * getAndAdd returns previous value and adds given value */ public void testGetAndAdd() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(1, a.getAndAdd(this, 2)); assertEquals(3, a.get(this)); assertEquals(3, a.getAndAdd(this, -4)); assertEquals(-1, a.get(this)); } /** * getAndDecrement returns previous value and decrements */ public void testGetAndDecrement() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(1, a.getAndDecrement(this)); assertEquals(0, a.getAndDecrement(this)); assertEquals(-1, a.getAndDecrement(this)); } /** * getAndIncrement returns previous value and increments */ public void testGetAndIncrement() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(1, a.getAndIncrement(this)); assertEquals(2, a.get(this)); a.set(this, -2); assertEquals(-2, a.getAndIncrement(this)); assertEquals(-1, a.getAndIncrement(this)); assertEquals(0, a.getAndIncrement(this)); assertEquals(1, a.get(this)); } /** * addAndGet adds given value to current, and returns current value */ public void testAddAndGet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(3, a.addAndGet(this, 2)); assertEquals(3, a.get(this)); assertEquals(-1, a.addAndGet(this, -4)); assertEquals(-1, a.get(this)); } /** * decrementAndGet decrements and returns current value */ public void testDecrementAndGet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(0, a.decrementAndGet(this)); assertEquals(-1, a.decrementAndGet(this)); assertEquals(-2, a.decrementAndGet(this)); assertEquals(-2, a.get(this)); } /** * incrementAndGet increments and returns current value */ public void testIncrementAndGet() { AtomicLongFieldUpdater<AtomicLongFieldUpdaterTest> a; a = updaterFor("x"); x = 1; assertEquals(2, a.incrementAndGet(this)); assertEquals(2, a.get(this)); a.set(this, -2); assertEquals(-1, a.incrementAndGet(this)); assertEquals(0, a.incrementAndGet(this)); assertEquals(1, a.incrementAndGet(this)); assertEquals(1, a.get(this)); } }