}
              }
            });

    assertTrue(at.compareAndSet(1.0, 2.0));
    awaitTermination(t);
    assertBitEquals(3.0, at.get());
  }

  /** repeated weakCompareAndSet succeeds in changing value when equal to expected */
  public void testWeakCompareAndSet() {
    double prev = Math.E;
    double unused = Math.E + Math.PI;
    AtomicDouble at = new AtomicDouble(prev);

                }
              }
            });

    assertTrue(at.compareAndSet(1.0, 2.0));
    awaitTermination(t);
    assertBitEquals(3.0, at.get());
  }

  /** repeated weakCompareAndSet succeeds in changing value when equal to expected */
  public void testWeakCompareAndSet() {
    double prev = Math.E;
    double unused = Math.E + Math.PI;
    AtomicDouble at = new AtomicDouble(prev);