rollback( );
				public void widgetSelected( SelectionEvent event )				{					String value = combo.getText( );					if ( value.equals( NONE ) )					{						value = null;					}					if ( canChangeDataSet( value ) )					{						try						{							startTrans( "" ); //$NON-NLS-1$							DataSetHandle dataSet = null;							if ( value != null )							{								dataSet = SessionHandleAdapter.getInstance( )										.getReportDesignHandle( )										.findDataSet( value );							}							inputElement.setDataSet( dataSet );							generateBindingColumns( );							getPropertyHandle( ).setStringValue( null );							commit( );						}						catch ( SemanticException e )						{							rollback( );							ExceptionHandler.handle( e );						}					}					else					{						combo.setText( getDataSetName( ) );					}				}