Java tutorial
/** * 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; import java.io.InputStream; import java.security.AccessController; import java.security.PrivilegedAction; import java.util.ArrayList; import java.util.List; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import org.apache.xml.security.algorithms.JCEMapper; import org.apache.xml.security.algorithms.SignatureAlgorithm; import org.apache.xml.security.c14n.Canonicalizer; import org.apache.xml.security.keys.keyresolver.KeyResolver; import org.apache.xml.security.transforms.Transform; import org.apache.xml.security.utils.ElementProxy; import org.apache.xml.security.utils.I18n; import org.apache.xml.security.utils.XMLUtils; import org.apache.xml.security.utils.resolver.ResourceResolver; import org.w3c.dom.Attr; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; /** * This class does the configuration of the library. This includes creating * the mapping of Canonicalization and Transform algorithms. Initialization is * done by calling {@link Init#init} which should be done in any static block * of the files of this library. We ensure that this call is only executed once. */ public class Init { /** The namespace for CONF file **/ public static final String CONF_NS = "http://www.xmlsecurity.org/NS/#configuration"; /** {@link org.apache.commons.logging} logging facility */ private static org.apache.commons.logging.Log log = org.apache.commons.logging.LogFactory.getLog(Init.class); /** Field alreadyInitialized */ private static boolean alreadyInitialized = false; /** * Method isInitialized * @return true if the library is already initialized. */ public synchronized static final boolean isInitialized() { return Init.alreadyInitialized; } /** * Method init * */ public synchronized static void init() { if (alreadyInitialized) { return; } InputStream is = AccessController.doPrivileged(new PrivilegedAction<InputStream>() { public InputStream run() { String cfile = System.getProperty("org.apache.xml.security.resource.config"); if (cfile == null) { return null; } return getClass().getResourceAsStream(cfile); } }); if (is == null) { dynamicInit(); } else { fileInit(is); } alreadyInitialized = true; } /** * Dynamically initialise the library by registering the default algorithms/implementations */ private static void dynamicInit() { // // Load the Resource Bundle - the default is the English resource bundle. // To load another resource bundle, call I18n.init(...) before calling this // method. // I18n.init("en", "US"); if (log.isDebugEnabled()) { log.debug("Registering default algorithms"); } try { // // Bind the default prefixes // ElementProxy.registerDefaultPrefixes(); // // Set the default Transforms // Transform.registerDefaultAlgorithms(); // // Set the default signature algorithms // SignatureAlgorithm.registerDefaultAlgorithms(); // // Set the default JCE algorithms // JCEMapper.registerDefaultAlgorithms(); // // Set the default c14n algorithms // Canonicalizer.registerDefaultAlgorithms(); // // Register the default resolvers // ResourceResolver.registerDefaultResolvers(); // // Register the default key resolvers // KeyResolver.registerDefaultResolvers(); } catch (Exception ex) { log.error(ex); ex.printStackTrace(); } } /** * Initialise the library from a configuration file */ private static void fileInit(InputStream is) { try { /* read library configuration file */ DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); dbf.setNamespaceAware(true); dbf.setValidating(false); DocumentBuilder db = dbf.newDocumentBuilder(); Document doc = db.parse(is); Node config = doc.getFirstChild(); for (; config != null; config = config.getNextSibling()) { if ("Configuration".equals(config.getLocalName())) { break; } } if (config == null) { log.error("Error in reading configuration file - Configuration element not found"); return; } for (Node el = config.getFirstChild(); el != null; el = el.getNextSibling()) { if (el == null || Node.ELEMENT_NODE != el.getNodeType()) { continue; } String tag = el.getLocalName(); if (tag.equals("ResourceBundles")) { Element resource = (Element) el; /* configure internationalization */ Attr langAttr = resource.getAttributeNode("defaultLanguageCode"); Attr countryAttr = resource.getAttributeNode("defaultCountryCode"); String languageCode = (langAttr == null) ? null : langAttr.getNodeValue(); String countryCode = (countryAttr == null) ? null : countryAttr.getNodeValue(); I18n.init(languageCode, countryCode); } if (tag.equals("CanonicalizationMethods")) { Element[] list = XMLUtils.selectNodes(el.getFirstChild(), CONF_NS, "CanonicalizationMethod"); for (int i = 0; i < list.length; i++) { String URI = list[i].getAttributeNS(null, "URI"); String JAVACLASS = list[i].getAttributeNS(null, "JAVACLASS"); try { Canonicalizer.register(URI, JAVACLASS); if (log.isDebugEnabled()) { log.debug("Canonicalizer.register(" + URI + ", " + JAVACLASS + ")"); } } catch (ClassNotFoundException e) { Object exArgs[] = { URI, JAVACLASS }; log.error(I18n.translate("algorithm.classDoesNotExist", exArgs)); } } } if (tag.equals("TransformAlgorithms")) { Element[] tranElem = XMLUtils.selectNodes(el.getFirstChild(), CONF_NS, "TransformAlgorithm"); for (int i = 0; i < tranElem.length; i++) { String URI = tranElem[i].getAttributeNS(null, "URI"); String JAVACLASS = tranElem[i].getAttributeNS(null, "JAVACLASS"); try { Transform.register(URI, JAVACLASS); if (log.isDebugEnabled()) { log.debug("Transform.register(" + URI + ", " + JAVACLASS + ")"); } } catch (ClassNotFoundException e) { Object exArgs[] = { URI, JAVACLASS }; log.error(I18n.translate("algorithm.classDoesNotExist", exArgs)); } catch (NoClassDefFoundError ex) { log.warn("Not able to found dependencies for algorithm, I'll keep working."); } } } if ("JCEAlgorithmMappings".equals(tag)) { Node algorithmsNode = ((Element) el).getElementsByTagName("Algorithms").item(0); if (algorithmsNode != null) { Element[] algorithms = XMLUtils.selectNodes(algorithmsNode.getFirstChild(), CONF_NS, "Algorithm"); for (int i = 0; i < algorithms.length; i++) { Element element = algorithms[i]; String id = element.getAttribute("URI"); JCEMapper.register(id, new JCEMapper.Algorithm(element)); } } } if (tag.equals("SignatureAlgorithms")) { Element[] sigElems = XMLUtils.selectNodes(el.getFirstChild(), CONF_NS, "SignatureAlgorithm"); for (int i = 0; i < sigElems.length; i++) { String URI = sigElems[i].getAttributeNS(null, "URI"); String JAVACLASS = sigElems[i].getAttributeNS(null, "JAVACLASS"); /** $todo$ handle registering */ try { SignatureAlgorithm.register(URI, JAVACLASS); if (log.isDebugEnabled()) { log.debug("SignatureAlgorithm.register(" + URI + ", " + JAVACLASS + ")"); } } catch (ClassNotFoundException e) { Object exArgs[] = { URI, JAVACLASS }; log.error(I18n.translate("algorithm.classDoesNotExist", exArgs)); } } } if (tag.equals("ResourceResolvers")) { Element[] resolverElem = XMLUtils.selectNodes(el.getFirstChild(), CONF_NS, "Resolver"); for (int i = 0; i < resolverElem.length; i++) { String JAVACLASS = resolverElem[i].getAttributeNS(null, "JAVACLASS"); String Description = resolverElem[i].getAttributeNS(null, "DESCRIPTION"); if ((Description != null) && (Description.length() > 0)) { if (log.isDebugEnabled()) { log.debug("Register Resolver: " + JAVACLASS + ": " + Description); } } else { if (log.isDebugEnabled()) { log.debug("Register Resolver: " + JAVACLASS + ": For unknown purposes"); } } try { ResourceResolver.register(JAVACLASS); } catch (Throwable e) { log.warn("Cannot register:" + JAVACLASS + " perhaps some needed jars are not installed", e); } } } if (tag.equals("KeyResolver")) { Element[] resolverElem = XMLUtils.selectNodes(el.getFirstChild(), CONF_NS, "Resolver"); List<String> classNames = new ArrayList<String>(resolverElem.length); for (int i = 0; i < resolverElem.length; i++) { String JAVACLASS = resolverElem[i].getAttributeNS(null, "JAVACLASS"); String Description = resolverElem[i].getAttributeNS(null, "DESCRIPTION"); if ((Description != null) && (Description.length() > 0)) { if (log.isDebugEnabled()) { log.debug("Register Resolver: " + JAVACLASS + ": " + Description); } } else { if (log.isDebugEnabled()) { log.debug("Register Resolver: " + JAVACLASS + ": For unknown purposes"); } } classNames.add(JAVACLASS); } KeyResolver.registerClassNames(classNames); } if (tag.equals("PrefixMappings")) { if (log.isDebugEnabled()) { log.debug("Now I try to bind prefixes:"); } Element[] nl = XMLUtils.selectNodes(el.getFirstChild(), CONF_NS, "PrefixMapping"); for (int i = 0; i < nl.length; i++) { String namespace = nl[i].getAttributeNS(null, "namespace"); String prefix = nl[i].getAttributeNS(null, "prefix"); if (log.isDebugEnabled()) { log.debug("Now I try to bind " + prefix + " to " + namespace); } ElementProxy.setDefaultPrefix(namespace, prefix); } } } } catch (Exception e) { log.error("Bad: ", e); e.printStackTrace(); } } }