private void filterOutAboveOrBelowGround(final Set<StendhalRPZone> zonesInRegion,final Boolean aboveGround){
  final Set<StendhalRPZone> removals=new HashSet<StendhalRPZone>();
  for (  StendhalRPZone zone : zonesInRegion) {
    if (aboveGround.booleanValue()) {
      if (zone.getLevel() < 0) {
        removals.add(zone);
      }
    }
 else {
      if (zone.getLevel() >= 0) {
        removals.add(zone);
      }
    }
  }
  zonesInRegion.removeAll(removals);
}

private void filterOutAboveOrBelowGround ( final Set < StendhalRPZone > zonesInRegion , final Boolean aboveGround ) { final Set < StendhalRPZone > removals = new HashSet < StendhalRPZone > ( ) ; for ( StendhalRPZone zone : zonesInRegion ) { if ( aboveGround . booleanValue ( ) ) { if ( zone . getLevel ( ) < 0 ) { removals . add ( zone ) ; } } else { if ( zone . getLevel ( ) >= 0 ) { removals . add ( zone ) ; } } } zonesInRegion . removeAll ( removals ) ; }
filter out zones above or below ground
