public void addTimeBoundsProvider(TimeBoundsProvider tbp){
  if (!timeBoundsProviders.contains(tbp)) {
    timeBoundsProviders.add(tbp);
    resetTimeBounds();
  }
}

public void addTimeBoundsProvider ( TimeBoundsProvider tbp ) { if ( ! timeBoundsProviders . contains ( tbp ) ) { timeBoundsProviders . add ( tbp ) ; resetTimeBounds ( ) ; } }
add a timeboundsprovider to the clock , so it knows the bounds of it ' s time range .
