public synchronized void addPvChangeListener(PvChangeListener l,int eventMask){
  Object oldListener=PvChangeListeners.get(l);
  PvChangeListeners.put(l,new Integer(eventMask));
  if (oldListener == null) {
    log.debug("+PvListener:" + String.valueOf(this) + "->"+ String.valueOf(l));
  }
}

public synchronized void addPvChangeListener ( PvChangeListener l , int eventMask ) { Object oldListener = PvChangeListeners . get ( l ) ; PvChangeListeners . put ( l , new Integer ( eventMask ) ) ; if ( oldListener == null ) { log . debug ( "+PvListener:" + String . valueOf ( this ) + "->" + String . valueOf ( l ) ) ; } }
add listener for pv changes with specified change events
