code: public static void sleep(final long duration, final TimeUnit unit) {
  		try {
  			Thread.sleep(unit.toMillis(duration));
  		} catch (InterruptedException e) {
  			LOG.trace("", e);
  			Thread.currentThread().interrupt();
  		}
  	}
docs: sleep 等待。已捕捉并处理 InterruptedException。
  
  @param duration
  等待时间
  @param unit
  时间单位