@Override
 public void onDisable() {
   log.info("Shutting down blockqueue and undothread, please wait.");
   bq.shouldrun = false;
   while (bq.isAlive()) {
     // wait
   }
   ut.shouldRun = false;
   while (ut.isAlive()) {
     // wait
   }
   log.info("WorldThreadit Disabled.");
 }