public void complete() {
    synchronized (this.timerTask) {
      if (this.complete) {
        LOG.warn("Timer already marked completed, ignoring!");
        return;
      }
      if (LOG.isDebugEnabled()) {
        LOG.debug("Marking timer as complete - no error notifications will be received for "
          + "this timer.");
      }
      this.complete = true;
    }
    this.timer.cancel();
  }
For all time forward, do not throw an error because the process has completed.
hbase-server/src/main/java/org/apache/hadoop/hbase/errorhandling/TimeoutExceptionInjector.java