Ptidej-v5.2-master/Ptidej Reporting Tests/src/net/sf/jasperreports/engine/util/xml/JRXPathExecuter.java
/*
 * ============================================================================
 * GNU Lesser General Public License
 * ============================================================================
 *
 * JasperReports - Free Java report-generating library.
 * Copyright (C) 2001-2006 JasperSoft Corporation http://www.jaspersoft.com
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307, USA.
 * 
 * JasperSoft Corporation
 * 303 Second Street, Suite 450 North
 * San Francisco, CA 94107
 * http://www.jaspersoft.com
 */
package net.sf.jasperreports.engine.util.xml;

import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.data.JRXmlDataSource;

import org.w3c.dom.Node;
import org.w3c.dom.NodeList;


/**
 * An XPath expression executer.
 * <p/>
 * {@link JRXmlDataSource XML data sources} delegate XPath executions to implementations
 * of this interface.
 * 
 * @author Lucian Chirita (lucianc@users.sourceforge.net)
 * @version $Id: JRXPathExecuter.java,v 1.1 2008/09/29 16:19:53 guehene Exp $
 * @see JRXPathExecuterFactory
 * @see JRXPathExecuterUtils
 */
public interface JRXPathExecuter
{

	/**
	 * Selects a node list by evaluating an XPath expression on a context node.
	 * 
	 * @param contextNode the context node (a document can also be used)
	 * @param expression the XPath expression
	 * @return the selected node list
	 * @throws JRException if the XPath evaluation failed
	 */
	NodeList selectNodeList(Node contextNode, String expression) throws JRException;

	
	/**
	 * Selects an object by evaluating an XPath expression on a context node.
	 * <p/>
	 * If the expression evaluates to a node list, the first node in the list should be returned.
	 * Otherwise, the primitive value resulted from the evaluation should be returned as a
	 * <code>java.lang.String</code>, <code>java.lang.Number</code> or <code>java.lang.Boolean</code>.
	 * 
	 * @param contextNode the context node (a document can also be used)
	 * @param expression the XPath expression
	 * @return the selected node or value
	 * @throws JRException if the XPath evaluation failed
	 */
	Object selectObject(Node contextNode, String expression) throws JRException;

}
