if (treeListener != null) tableTree.removeTreeListener(treeListener); treeListener = null;
public void dispose () {		Table table = tableTree.getTable();	if (this.column > -1 && this.column < table.getColumnCount()){		TableColumn tableColumn = table.getColumn(this.column);		tableColumn.removeListener(SWT.Resize, columnListener);		tableColumn.removeListener(SWT.Move, columnListener);	}	tableTree = null;	item = null;	column = -1;		super.dispose();}