switchParamterType( );
changeDataType( ); if ( allowBlank != null && !allowBlank.isDisposed( ) ) { if ( DesignChoiceConstants.PARAM_TYPE_STRING.equals( getSelectedDataType( ) ) ) { allowBlank.setEnabled( true ); } else { allowBlank.setEnabled( false ); allowBlank.setSelection( false );  checkBoxChange( allowBlank, CHECKBOX_ALLOW_BLANK );  } }
			public void widgetSelected( SelectionEvent e )			{				switchParamterType( );			}