public void clearSourceElements(){
  for (  PNode node : sourceElements) {
    SourceHandle.removeSourceHandleFrom(node);
  }
  sourceElements.clear();
  selectionModel.fireSelectionChanged();
}

public void clearSourceElements ( ) { for ( PNode node : sourceElements ) { SourceHandle . removeSourceHandleFrom ( node ) ; } sourceElements . clear ( ) ; selectionModel . fireSelectionChanged ( ) ; }
clear all source elements .
