protected void addToQuarantineQueue(NodePortTuple npt){
  if (quarantineQueue.contains(npt) == false) {
    quarantineQueue.add(npt);
  }
}

protected void addToQuarantineQueue ( NodePortTuple npt ) { if ( quarantineQueue . contains ( npt ) == false ) { quarantineQueue . add ( npt ) ; } }
add a switch port to the quarantine queue . schedule the quarantine task if the quarantine queue was empty before adding this switch port .
