code: public boolean removeStopCriterion(StopCriterion stopCriterion){
          // acquire status lock
          synchronized(statusLock){
              // assert idle
              assertIdle("Cannot remove stop criterion.");
              // remove from checker
              if (stopCriterionChecker.remove(stopCriterion)){
                  // log
                  LOGGER.debug("{}: removed stop criterion {}", this, stopCriterion);
                  return true;
              } else {
                  return false;
              }
          }
      }
docs: Removes a stop criterion. In case this stop criterion had not been added, <code>false</code> is returned.
  Note that this method may only be called when the search is idle.
  
  @param stopCriterion stop criterion to be removed
  @return <code>true</code> if the stop criterion has been successfully removed
  @throws SearchException if the search is not idle