/*******************************************************************************
* Copyright (c) 2000, 2015 IBM Corporation and others.
* 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:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.jface.viewers;
/**
* A cell modifier is used to access the data model from a cell
* editor in an abstract way. It offers methods to:
* <ul>
* <li>to check if a a model element's property can be edited or not</li>
* <li>retrieve a value a model element's property</li>
* <li>to store a cell editor's value back into the model
* element's property</li>
* </ul>
* <p>
* This interface should be implemented by classes that wish to
* act as cell modifiers.
* </p>
*/
public interface ICellModifier {
/**
* Checks whether the given property of the given element can be
* modified.
*
* @param element the element
* @param property the property
* @return <code>true</code> if the property can be modified,
* and <code>false</code> if it is not modifiable
*/
public boolean canModify(Object element, String property);
/**
* Returns the value for the given property of the given element.
* Returns <code>null</code> if the element does not have the given property.
*
* @param element the element
* @param property the property
* @return the property value
*/
public Object getValue(Object element, String property);
/**
* Modifies the value for the given property of the given element.
* Has no effect if the element does not have the given property,
* or if the property cannot be modified.
* <p>
* Note that it is possible for an SWT Item to be passed instead of
* the model element. To handle this case in a safe way, use:
* <pre>
* if (element instanceof Item) {
* element = ((Item) element).getData();
* }
* // modify the element's property here
* </pre>
* </p>
*
* @param element the model element or SWT Item (see above)
* @param property the property
* @param value the new property value
*
* @see org.eclipse.swt.widgets.Item
*/
public void modify(Object element, String property, Object value);
}