FileDocCategorySizeDatePackage
AtomicReferenceFieldUpdaterTest.javaAPI DocAndroid 1.5 API5687Wed May 06 22:41:02 BST 2009tests.api.java.util.concurrent

AtomicReferenceFieldUpdaterTest

public class AtomicReferenceFieldUpdaterTest extends JSR166TestCase

Fields Summary
volatile Integer
x
Object
z
Integer
w
Constructors Summary
Methods Summary
public static voidmain(java.lang.String[] args)


        
        junit.textui.TestRunner.run(suite());
public static junit.framework.Testsuite()

        return new TestSuite(AtomicReferenceFieldUpdaterTest.class);
public voidtestCompareAndSet()
compareAndSet succeeds in changing value if equal to expected else fails

        AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>a;
        try {
            a = AtomicReferenceFieldUpdater.newUpdater(AtomicReferenceFieldUpdaterTest.class, Integer.class, "x");
        } catch (RuntimeException ok) {
            return;
        }
        x = one;
        assertTrue(a.compareAndSet(this,one,two));
        assertTrue(a.compareAndSet(this,two,m4));
        assertEquals(m4,a.get(this));
        assertFalse(a.compareAndSet(this,m5,seven));
        assertFalse((seven == a.get(this)));
        assertTrue(a.compareAndSet(this,m4,seven));
        assertEquals(seven,a.get(this));
public voidtestCompareAndSetInMultipleThreads()
compareAndSet in one thread enables another waiting for value to succeed

        x = one;
        final AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>a;
        try {
            a = AtomicReferenceFieldUpdater.newUpdater(AtomicReferenceFieldUpdaterTest.class, Integer.class, "x");
        } catch (RuntimeException ok) {
            return;
        }

        Thread t = new Thread(new Runnable() {
                public void run() {
                    while(!a.compareAndSet(AtomicReferenceFieldUpdaterTest.this, two, three)) Thread.yield();
                }});
        try {
            t.start();
            assertTrue(a.compareAndSet(this, one, two));
            t.join(LONG_DELAY_MS);
            assertFalse(t.isAlive());
            assertEquals(a.get(this), three);
        }
        catch(Exception e) {
            unexpectedException();
        }
public voidtestConstructor()
Construction with non-existent field throws RuntimeException

        try{
            AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>
                a = AtomicReferenceFieldUpdater.newUpdater
                (AtomicReferenceFieldUpdaterTest.class, Integer.class, "y");
            shouldThrow();
        }
        catch (RuntimeException rt) {}
public voidtestConstructor2()
construction with field not of given type throws RuntimeException

        try{
            AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>
                a = AtomicReferenceFieldUpdater.newUpdater
                (AtomicReferenceFieldUpdaterTest.class, Integer.class, "z");
            shouldThrow();
        }
        catch (RuntimeException rt) {}
public voidtestConstructor3()
Constructor with non-volatile field throws exception

        try{
            AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>
                a = AtomicReferenceFieldUpdater.newUpdater
                (AtomicReferenceFieldUpdaterTest.class, Integer.class, "w");
            shouldThrow();
        }
        catch (RuntimeException rt) {}
public voidtestGetAndSet()
getAndSet returns previous value and sets to given value

        AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>a;
        try {
            a = AtomicReferenceFieldUpdater.newUpdater(AtomicReferenceFieldUpdaterTest.class, Integer.class, "x");
        } catch (RuntimeException ok) {
            return;
        }
        x = one;
        assertEquals(one,a.getAndSet(this, zero));
        assertEquals(zero,a.getAndSet(this,m10));
        assertEquals(m10,a.getAndSet(this,1));
public voidtestGetSet()
get returns the last value set or assigned

        AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>a;
        try {
            a = AtomicReferenceFieldUpdater.newUpdater(AtomicReferenceFieldUpdaterTest.class, Integer.class, "x");
        } catch (RuntimeException ok) {
            return;
        }
        x = one;
        assertEquals(one,a.get(this));
        a.set(this,two);
        assertEquals(two,a.get(this));
        a.set(this,-3);
        // BEGIN android-changed
        assertEquals(new Integer(-3),a.get(this));
        // END android-changed
public voidtestWeakCompareAndSet()
repeated weakCompareAndSet succeeds in changing value when equal to expected

        AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer>a;
        try {
            a = AtomicReferenceFieldUpdater.newUpdater(AtomicReferenceFieldUpdaterTest.class, Integer.class, "x");
        } catch (RuntimeException ok) {
            return;
        }
        x = one;
        while(!a.weakCompareAndSet(this,one,two));
        while(!a.weakCompareAndSet(this,two,m4));
        assertEquals(m4,a.get(this));
        while(!a.weakCompareAndSet(this,m4,seven));
        assertEquals(seven,a.get(this));