org.apache.xml.security.utils.XPathFactory Maven / Gradle / Ivy
/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.xml.security.utils;
/**
* A Factory to return an XPathAPI instance. If Xalan is available it returns XalanXPathAPI. If not, then
* it returns JDKXPathAPI.
*/
public abstract class XPathFactory {
private static boolean xalanInstalled;
static {
try {
Class funcTableClass =
ClassLoaderUtils.loadClass("org.apache.xpath.compiler.FunctionTable", XPathFactory.class);
if (funcTableClass != null) {
xalanInstalled = true;
}
} catch (Exception e) { //NOPMD
//ignore
}
}
protected static synchronized boolean isXalanInstalled() {
return xalanInstalled;
}
/**
* Get a new XPathFactory instance
*/
public static XPathFactory newInstance() {
if (!isXalanInstalled()) {
return new JDKXPathFactory();
}
// Xalan is available
if (XalanXPathAPI.isInstalled()) {
return new XalanXPathFactory();
}
// Some problem was encountered in fixing up the Xalan FunctionTable so fall back to the
// JDK implementation
return new JDKXPathFactory();
}
/**
* Get a new XPathAPI instance
*/
public abstract XPathAPI newXPathAPI();
}