if (current == State.OPEN) {
            long timeSinceLastFailure = System.currentTimeMillis() - lastFailureTime.get();
            if (timeSinceLastFailure > timeoutMillis) {
                if (state.compareAndSet(State.OPEN, State.HALF_OPEN)) {
                    stateChangeTime.set(System.currentTimeMillis());
                    halfOpenSuccesses.set(0);

        // First initialization
        if (client.isInit.compareAndSet(false, true)) {
            client.init();
        }
        assertTrue("Client should be initialized", client.isInit.get());

        // Second initialization attempt should be no-op
        boolean secondInit = client.isInit.compareAndSet(false, true);
        assertFalse("Second initialization should not occur", secondInit);

   * @param update the new value
   * @return true if successful. False return indicates that the actual value was not equal to the
   *     expected value.
   */
  public final boolean compareAndSet(int i, double expect, double update) {
    return longs.compareAndSet(i, doubleToRawLongBits(expect), doubleToRawLongBits(update));
  }

  /**
   * Atomically sets the element at position {@code i} to the given updated value if the current

     * interrupt, yet it will still run, since interruptTask will leave the runner value null,
     * allowing the CAS below to succeed.
     */
    Thread currentThread = Thread.currentThread();
    if (!compareAndSet(null, currentThread)) {
      return; // someone else has run or is running.
    }

    boolean run = !isDone();
    T result = null;
    Throwable error = null;
    try {
      if (run) {

   * AtomicInteger's atomic operations, with some help from ConcurrentMap's atomic operations on
   * creation and removal (including automatic removal of zeroes). If the modification of an
   * AtomicInteger results in zero, we compareAndSet the value to zero; if that succeeds, we remove
   * the entry from the Map. If another operation sees a zero in the map, it knows that the entry is

        AbstractFutureState<?> future, @Nullable Waiter expect, @Nullable Waiter update) {
      return waitersUpdater.compareAndSet(future, expect, update);
    }

    @Override
    boolean casListeners(
        AbstractFutureState<?> future, @Nullable Listener expect, Listener update) {
      return listenersUpdater.compareAndSet(future, expect, update);
    }

    @Override

                if (shouldExecute && anyPredecessorFailed) {
                    // We'll run the step but mark it as SKIPPED instead of SCHEDULED
                    if (step.status.compareAndSet(CREATED, SKIPPED)) {
                        logger.debug(
                                "Running after:* step {} for cleanup but marking it as SKIPPED because a predecessor failed",
                                step);

      long newValue;
      do {
        oldValue = data.get(longIndex);
        newValue = oldValue | mask;
        if (oldValue == newValue) {
          return false;
        }
      } while (!data.compareAndSet(longIndex, oldValue, newValue));

      // We turned the bit on, so increment bitCount.
      bitCount.increment();
      return true;
    }

    boolean get(long bitIndex) {

        AbstractFutureState<?> future, @Nullable Waiter expect, @Nullable Waiter update) {
      return waitersUpdater.compareAndSet(future, expect, update);
    }

    @Override
    boolean casListeners(
        AbstractFutureState<?> future, @Nullable Listener expect, Listener update) {
      return listenersUpdater.compareAndSet(future, expect, update);
    }

    @Override

    for (int i = 0; i < 10; i++) {
      int expectedCount = i;
      list.add(
          new Runnable() {
            @Override
            public void run() {
              integer.compareAndSet(expectedCount, expectedCount + 1);
            }
          },
          directExecutor());
    }
    list.execute();
    assertEquals(10, integer.get());
  }