code: @Deprecated
      public synchronized boolean awaitTerminationAfterShutdown(long maxWaitTime) throws InterruptedException {
          if (!shutdown_)
              throw new IllegalStateException();
  
          if (poolSize_ == 0)
              return true;
  
          long waitTime = maxWaitTime;
  
          if (waitTime <= 0)
              return false;
  
          long start = System.currentTimeMillis();
  
          for (;;) {
              wait(waitTime);
  
              if (poolSize_ == 0)
                  return true;
  
              waitTime = maxWaitTime - (System.currentTimeMillis() - start);
  
              if (waitTime <= 0)
                  return false;
          }
      }
docs: Wait for a shutdown pool to fully terminate, or until the timeout
  has expired. This method may only be called <em>after</em> invoking
  shutdownNow or
  shutdownAfterProcessingCurrentlyQueuedTasks.
  
  @param maxWaitTime
  the maximum time in milliseconds to wait
  @return true if the pool has terminated within the max wait period
  @exception IllegalStateException
  if shutdown has not been requested
  @exception InterruptedException
  if the current thread has been interrupted in the course of
  waiting
  
  @deprecated