if ( ( (DbObject) selection[0].getData( ) ).getType( ) == DbObject.PROCEDURE_TYPE )
if ( selection[0].getData( ) instanceof DbObject ) { if ( ( (DbObject) selection[0].getData( ) ).getType( ) == DbObject.PROCEDURE_TYPE ) { event.doit = false; return; } } else if ( selection[0].getData( ) instanceof ProcedureParameter )
			public void dragStart( DragSourceEvent event )			{				TreeItem[] selection = availableDbObjectsTree.getSelection( );				if ( selection.length > 0						&& selection[0].getData( ) instanceof DbObject )				{					if ( ( (DbObject) selection[0].getData( ) ).getType( ) == DbObject.PROCEDURE_TYPE )					{						event.doit = false;						return;					};				}				else if ( selection.length <= 0						|| selection[0].getData( ) == null )				{					event.doit = false;					return;				}			}