コード例 #1
0
 /** repeated weakCompareAndSet succeeds in changing value when equal to expected */
 public void testWeakCompareAndSet() {
   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)) ;
   assertSame(m4, a.get(this));
   while (!a.weakCompareAndSet(this, m4, seven)) ;
   assertSame(seven, a.get(this));
 }
コード例 #2
0
 /** get returns the last value lazySet by same thread */
 public void testGetLazySet() {
   AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> a;
   try {
     a =
         AtomicReferenceFieldUpdater.newUpdater(
             AtomicReferenceFieldUpdaterTest.class, Integer.class, "x");
   } catch (RuntimeException ok) {
     return;
   }
   x = one;
   assertSame(one, a.get(this));
   a.lazySet(this, two);
   assertSame(two, a.get(this));
   a.lazySet(this, m3);
   assertSame(m3, a.get(this));
 }
コード例 #3
0
  /** compareAndSet in one thread enables another waiting for value to succeed */
  public void testCompareAndSetInMultipleThreads() throws Exception {
    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 CheckedRunnable() {
              public void realRun() {
                while (!a.compareAndSet(AtomicReferenceFieldUpdaterTest.this, two, three))
                  Thread.yield();
              }
            });

    t.start();
    assertTrue(a.compareAndSet(this, one, two));
    t.join(LONG_DELAY_MS);
    assertFalse(t.isAlive());
    assertSame(a.get(this), three);
  }