org.eclipse.jface.text/src/org/eclipse/jface/text/presentation/IPresentationDamager.java

/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jface.text.presentation;



import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITypedRegion;


/**
 * Presentation damagers are used by a presentation reconciler to determine the 
 * region of the document's presentation which must be rebuilt because of the 
 * occurrence of a document change. A presentation damager is assumed to be 
 * specific for a particular document content type. A presentation damager is 
 * expected to return a damage region which is a valid input for a presentation repairer.
 * I.e. having access to the damage region only the repairer must be able to derive
 * all the information neede to sucessfully repair this region.<p>
 * This interface must either be implemented by clients or clients use the rule-based
 * default implementation <code>RuleBasedDamagerRepairer</code>. Implementers should be
 * registered with a presentation reconciler in order get involved in the reconciling 
 * process.
 *
 * @see IPresentationReconciler
 * @see IDocument
 * @see DocumentEvent
 * @see IPresentationRepairer
 */
public interface IPresentationDamager {
	
	/**
	 * Tells the presentation damager on which document it will work.
	 *
	 * @param document the damager's working document
	 */
	void setDocument(IDocument document);
	
	/**
	 * Returns the damage in the document's presentation caused by the given document change.
	 * The damage is restricted to the specified partition for which the presentation damager is
	 * responsible. The damage may also depend on whether the document change also caused changes
	 * of the document's partitioning.
	 *
	 * @param partition the partition inside which the damage must be determined
	 * @param event the event describing the change whose damage must be determined
	 * @param documentPartitioningChange indicates whether the given change changed the document's partitioning
	 * @return the computed damage
	 */
	IRegion getDamageRegion(ITypedRegion partition, DocumentEvent event, boolean documentPartitioningChanged);
}