GetNodeAtOrBeforeOffsetVisitor.java

/*******************************************************************************
 * Copyright © 2008, 2013 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.edt.ide.core.ast;

import org.eclipse.edt.compiler.core.ast.AbstractASTNodeVisitor;
import org.eclipse.edt.compiler.core.ast.Node;

public class GetNodeAtOrBeforeOffsetVisitor extends AbstractASTNodeVisitor {

	private Node targetNode;
	private int targetOffset;
	
	public GetNodeAtOrBeforeOffsetVisitor(int offset) {
		targetOffset = offset;
	}
	
	public Node getNode() {
		return targetNode;
	}
	
	/**
	 * if the offset is at a white space/comments, it will return the most close parent node for this offset
	 * the caller of this method needs to determine if this is what they want. 
	 * the offset is AT or to the right of the node offset and the cursor is to(NOT at) the left of the end of node
	 * in other words, it includes the node offset, but exclude the offset+length of the node
	 *
	 * @param node
	 * @return
	 */
	protected boolean isNodeAtOffset(Node node)
	{
		if(node.getOffset() <= targetOffset)
		{
			//we found the target node
			targetNode = node;			
			return true;
		}		
		return false;
	}
	
	public boolean visitNode(Node node) {
		return isNodeAtOffset(node);
	}
	
	public void endVisitNode(Node node) {
	}
}