Java tutorial
//package com.java2s; /* * Copyright 2010-2014 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"). * You may not use this file except in compliance with the License. * A copy of the License is located at * * http://aws.amazon.com/apache2.0 * * or in the "license" file accompanying this file. This file 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. */ import com.sun.org.apache.xml.internal.dtm.DTMManager; import com.sun.org.apache.xml.internal.dtm.ref.DTMManagerDefault; import com.sun.org.apache.xpath.internal.XPathContext; public class Main { /** The default property name to load the Xalan DTM manager. */ private static final String DTM_MANAGER_DEFAULT_PROP_NAME = "com.sun.org.apache.xml.internal.dtm.DTMManager"; /** * Used to optimize performance by avoiding expensive file access every time * a DTMManager is constructed as a result of constructing a Xalan xpath * context! */ private static void speedUpDTMManager() { // https://github.com/aws/aws-sdk-java/issues/238 // http://stackoverflow.com/questions/6340802/java-xpath-apache-jaxp-implementation-performance String className = System.getProperty(DTM_MANAGER_DEFAULT_PROP_NAME); if (className == null) { DTMManager dtmManager = new XPathContext().getDTMManager(); if (dtmManager instanceof DTMManagerDefault) { // This would avoid the file system to be accessed every time // the internal XPathContext is instantiated. System.setProperty(DTM_MANAGER_DEFAULT_PROP_NAME, DTMManagerDefault.class.getName()); } } } }