void awaitWaiting() {
      while (!isBlocked()) {
        if (getState() == State.TERMINATED) {
          throw new RuntimeException("Thread exited");
        }
        Thread.yield();
      }
    }

    private boolean isBlocked() {
      return getState() == Thread.State.WAITING && LockSupport.getBlocker(this) == future;
    }
  }

    void awaitWaiting() {
      while (!isBlocked()) {
        if (getState() == State.TERMINATED) {
          throw new RuntimeException("Thread exited");
        }
        Thread.yield();
      }
    }

    private boolean isBlocked() {
      return getState() == Thread.State.WAITING && LockSupport.getBlocker(this) == future;
    }
  }

   * Returns whether this monitor is occupied by any thread. This method is designed for use in
   * monitoring of the system state, not for synchronization control.
   */
  public boolean isOccupied() {
    return lock.isLocked();
  }

  /**
   * Returns whether the current thread is occupying this monitor (has entered more times than it
   * has left).
   */
  public boolean isOccupiedByCurrentThread() {