}
public Scheduler removeTimerNodeScheduler( int nodeId, TupleKey key ) {
Map<TupleKey, Scheduler> timers = timerNodeSchedulers.get( nodeId );
if( timers != null ) {
Scheduler scheduler = timers.remove( key );
if( timers.isEmpty() ) {
timerNodeSchedulers.remove( nodeId );
}
return scheduler;
}