--- jsr166/src/test/tck/AtomicReferenceTest.java 2003/09/20 18:20:07 1.4 +++ jsr166/src/test/tck/AtomicReferenceTest.java 2009/11/17 06:58:50 1.13 @@ -1,8 +1,9 @@ /* - * Written by members of JCP JSR-166 Expert Group and released to the - * public domain. Use, modify, and redistribute this code in any way - * without acknowledgement. Other contributors include Andrew Wright, - * Jeffrey Hayes, Pat Fischer, Mike Judd. + * 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/licenses/publicdomain + * Other contributors include Andrew Wright, Jeffrey Hayes, + * Pat Fisher, Mike Judd. */ import junit.framework.*; @@ -18,37 +19,49 @@ public class AtomicReferenceTest extends } /** - * + * constructor initializes to given value */ - public void testConstructor(){ + public void testConstructor() { AtomicReference ai = new AtomicReference(one); assertEquals(one,ai.get()); } /** - * + * default constructed initializes to null */ - public void testConstructor2(){ + public void testConstructor2() { AtomicReference ai = new AtomicReference(); assertNull(ai.get()); } /** - * + * get returns the last value set */ - public void testGetSet(){ + public void testGetSet() { AtomicReference ai = new AtomicReference(one); assertEquals(one,ai.get()); ai.set(two); assertEquals(two,ai.get()); ai.set(m3); assertEquals(m3,ai.get()); - } + + /** + * get returns the last value lazySet in same thread + */ + public void testGetLazySet() { + AtomicReference ai = new AtomicReference(one); + assertEquals(one,ai.get()); + ai.lazySet(two); + assertEquals(two,ai.get()); + ai.lazySet(m3); + assertEquals(m3,ai.get()); + } + /** - * + * compareAndSet succeeds in changing value if equal to expected else fails */ - public void testCompareAndSet(){ + public void testCompareAndSet() { AtomicReference ai = new AtomicReference(one); assertTrue(ai.compareAndSet(one,two)); assertTrue(ai.compareAndSet(two,m4)); @@ -60,21 +73,41 @@ public class AtomicReferenceTest extends } /** - * + * compareAndSet in one thread enables another waiting for value + * to succeed */ - public void testWeakCompareAndSet(){ + public void testCompareAndSetInMultipleThreads() throws Exception { + final AtomicReference ai = new AtomicReference(one); + Thread t = new Thread(new CheckedRunnable() { + public void realRun() { + while (!ai.compareAndSet(two, three)) + Thread.yield(); + }}); + + t.start(); + assertTrue(ai.compareAndSet(one, two)); + t.join(LONG_DELAY_MS); + assertFalse(t.isAlive()); + assertEquals(ai.get(), three); + } + + /** + * repeated weakCompareAndSet succeeds in changing value when equal + * to expected + */ + public void testWeakCompareAndSet() { AtomicReference ai = new AtomicReference(one); - while(!ai.weakCompareAndSet(one,two)); - while(!ai.weakCompareAndSet(two,m4)); + while (!ai.weakCompareAndSet(one,two)); + while (!ai.weakCompareAndSet(two,m4)); assertEquals(m4,ai.get()); - while(!ai.weakCompareAndSet(m4,seven)); + while (!ai.weakCompareAndSet(m4,seven)); assertEquals(seven,ai.get()); } /** - * + * getAndSet returns previous value and sets to given value */ - public void testGetAndSet(){ + public void testGetAndSet() { AtomicReference ai = new AtomicReference(one); assertEquals(one,ai.getAndSet(zero)); assertEquals(zero,ai.getAndSet(m10)); @@ -82,26 +115,31 @@ public class AtomicReferenceTest extends } /** - * + * a deserialized serialized atomic holds same value */ - public void testSerialization() { + public void testSerialization() throws Exception { AtomicReference l = new AtomicReference(); - try { - l.set(one); - ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); - ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); - out.writeObject(l); - out.close(); - - ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); - ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); - AtomicReference r = (AtomicReference) in.readObject(); - assertEquals(l.get(), r.get()); - } catch(Exception e){ - unexpectedException(); - } + l.set(one); + ByteArrayOutputStream bout = new ByteArrayOutputStream(10000); + ObjectOutputStream out = new ObjectOutputStream(new BufferedOutputStream(bout)); + out.writeObject(l); + out.close(); + + ByteArrayInputStream bin = new ByteArrayInputStream(bout.toByteArray()); + ObjectInputStream in = new ObjectInputStream(new BufferedInputStream(bin)); + AtomicReference r = (AtomicReference) in.readObject(); + assertEquals(l.get(), r.get()); } -} + /** + * toString returns current value. + */ + public void testToString() { + AtomicReference ai = new AtomicReference(one); + assertEquals(ai.toString(), one.toString()); + ai.set(two); + assertEquals(ai.toString(), two.toString()); + } +}