org.apache.taglibs.standard.tag.common.xml.XPathUtil Maven / Gradle / Ivy
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2012 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*
*
* This file incorporates work covered by the following copyright and
* permission notice:
*
* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.taglibs.standard.tag.common.xml;
import java.util.List;
import java.util.Vector;
import java.security.AccessController;
import java.security.PrivilegedAction;
import javax.servlet.jsp.JspTagException;
import javax.servlet.jsp.PageContext;
import javax.servlet.jsp.tagext.Tag;
import javax.servlet.jsp.tagext.TagSupport;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import javax.xml.xpath.XPathVariableResolver;
import javax.xml.xpath.XPathFactoryConfigurationException;
import org.apache.taglibs.standard.resources.Resources;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/**
* Support for tag handlers that evaluate XPath expressions.
*
* @author Shawn Bayern
* @author Ramesh Mandava ( [email protected] )
* @author Pierre Delisle ( [email protected] )
* @author Dongbin Nie
*/
// would ideally be a base class, but some of our user handlers already
// have their own parents
public class XPathUtil {
//*********************************************************************
// Constructor
/**
* Constructs a new XPathUtil object associated with the given
* PageContext.
*/
public XPathUtil(PageContext pc) {
pageContext = pc;
}
//*********************************************************************
// Support for JSTL variable resolution
// The URLs
private static final String PAGE_NS_URL
= "http://java.sun.com/jstl/xpath/page";
private static final String REQUEST_NS_URL
= "http://java.sun.com/jstl/xpath/request";
private static final String SESSION_NS_URL
= "http://java.sun.com/jstl/xpath/session";
private static final String APP_NS_URL
= "http://java.sun.com/jstl/xpath/app";
private static final String PARAM_NS_URL
= "http://java.sun.com/jstl/xpath/param";
private static final String INITPARAM_NS_URL
= "http://java.sun.com/jstl/xpath/initParam";
private static final String COOKIE_NS_URL
= "http://java.sun.com/jstl/xpath/cookie";
private static final String HEADER_NS_URL
= "http://java.sun.com/jstl/xpath/header";
//*********************************************************************
// Support for XPath evaluation
private PageContext pageContext;
private static final String XPATH_FACTORY_CLASS_NAME =
"org.apache.taglibs.standard.tag.common.xml.JSTLXPathFactory";
private static XPathFactory XPATH_FACTORY;
private static JSTLXPathNamespaceContext jstlXPathNamespaceContext = null;
private static DocumentBuilderFactory dbf = null;
static {
initXPathFactory();
initXPathNamespaceContext();
initDocumentBuilderFactory();
}
private static void initXPathFactory() {
// If the system property DEFAULT_PROPERTY_NAME + ":uri" is present,
// where uri is the parameter to this method, then its value is read
// as a class name. The method will try to create a new instance of
// this class by using the class loader, and returns it if it is
// successfully created.
if (System.getSecurityManager() != null) {
AccessController.doPrivileged(new PrivilegedAction