/*******************************************************************************
* Copyright (c) 2007, 2010 Association for Decentralized Information Management
* in Industry THTH ry.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* VTT Technical Research Centre of Finland - initial API and implementation
*******************************************************************************/
package org.simantics.g2d.diagram.handler;
import org.simantics.g2d.diagram.IDiagram;
import org.simantics.g2d.element.IElement;
/**
* Keeps a map between an element and its back-end object (KEY_OBJECT)
*
* @author Toni Kalajainen
*/
public interface DataElementMap extends DiagramHandler {
/**
* Get the element with given data (KEY_OBJECT)
*
* @param data the data object to find an element for
* @return element or null if no element has the data
*
* @throws NullPointerException if diagram or data is null
*/
IElement getElement(IDiagram d, Object data);
/**
* Get data related to an element
*
* @param element the element to get a back-end data object for
* @return data or null
*
* @throws NullPointerException if diagram or element is null
*/
Object getData(IDiagram d, IElement element);
}