public NetworkSelectionEvent(final NetworkPanel source,final Set<PNode> oldSelection,final Set<PNode> selection){
  super(source);
  this.oldSelection=Collections.unmodifiableSet(oldSelection);
  this.selection=Collections.unmodifiableSet(selection);
}

public NetworkSelectionEvent ( final NetworkPanel source , final Set < PNode > oldSelection , final Set < PNode > selection ) { super ( source ) ; this . oldSelection = Collections . unmodifiableSet ( oldSelection ) ; this . selection = Collections . unmodifiableSet ( selection ) ; }
create a new network selection event with the specified source .
