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.axis2.metadata.registry; import org.apache.axis2.java.security.AccessController; import org.apache.axis2.jaxws.ClientConfigurationFactory; import org.apache.axis2.jaxws.ExceptionFactory; import org.apache.axis2.jaxws.util.Constants; import org.apache.axis2.jaxws.wsdl.WSDLReaderConfigurator; import org.apache.axis2.jaxws.wsdl.WSDLReaderConfiguratorImpl; import org.apache.axis2.metadata.factory.ResourceFinderFactory; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import java.io.BufferedReader; import java.io.File; import java.io.InputStreamReader; import java.net.URL; import java.security.PrivilegedActionException; import java.security.PrivilegedExceptionAction; import java.util.Hashtable; import java.util.Map; public class MetadataFactoryRegistry { private static Log log = LogFactory.getLog(MetadataFactoryRegistry.class); private static String configurationFileLoc = null; private final static Map<Class, Object> table; static { table = new Hashtable<Class, Object>(); table.put(ResourceFinderFactory.class, new ResourceFinderFactory()); table.put(ClientConfigurationFactory.class, new ClientConfigurationFactory()); table.put(WSDLReaderConfigurator.class, new WSDLReaderConfiguratorImpl()); if (configurationFileLoc == null) { if (log.isDebugEnabled()) { log.debug("A configuration file location was not set. The " + "following location will be used: " + Constants.METADATA_REGISTRY_CONFIG_FILE); } configurationFileLoc = Constants.METADATA_REGISTRY_CONFIG_FILE; } loadConfigFromFile(); } /** * FactoryRegistry is currently a static singleton */ private MetadataFactoryRegistry() { } /** * getFactory * @param intface of the Factory * @return Object that is the factory implementation for the intface */ public static Object getFactory(Class intface) { return table.get(intface); } /** * setFactory * @param intface * @param factoryObject */ public static void setFactory(Class intface, Object factoryObject) { table.put(intface, factoryObject); } /** * This method will load a file, if it exists, that contains a list * of interfaces and custom implementations. This allows for non- * programmatic registration of custom interface implementations * with the MDQ layer. */ private static void loadConfigFromFile() { String pairSeparator = "|"; try { ClassLoader classLoader = getContextClassLoader(null); URL url = null; url = classLoader.getResource(configurationFileLoc); if (url == null) { File file = new File(configurationFileLoc); url = file.toURL(); } // the presence of this file is optional if (url != null) { if (log.isDebugEnabled()) { log.debug("Found URL to MetadataFactoryRegistry configuration file: " + configurationFileLoc); } BufferedReader reader = new BufferedReader(new InputStreamReader(url.openStream())); String line = reader.readLine(); // the separator of the file is the '|' character // to the left of the separator will be the interface and // to the right will be the custom implementation if (line != null && line.indexOf("|") != -1) { String interfaceName = line.substring(0, line.indexOf(pairSeparator)); String implName = line.substring(line.indexOf(pairSeparator) + 1, line.length()); if (log.isDebugEnabled()) { log.debug("For registered class: " + interfaceName + " the " + "following implementation was found: " + implName); } Class intf = classLoader.loadClass(interfaceName); Class impl = classLoader.loadClass(implName); // if we could load both we need to register them with our // internal registry if (intf != null && impl != null) { if (log.isDebugEnabled()) { log.debug("Loaded both interface and implementation class: " + interfaceName + ":" + implName); } if (impl.getEnclosingClass() == null) { table.put(intf, impl.newInstance()); } else { if (log.isWarnEnabled()) { log.warn("The implementation class: " + impl.getClass().getName() + " could not be lregistered because it is an inner class. " + "In order to register file-based overrides, implementations " + "must be public outer classes."); } } } else { if (log.isDebugEnabled()) { log.debug("Could not load both interface and implementation class: " + interfaceName + ":" + implName); } } } else { if (log.isDebugEnabled()) { log.debug("Did not find File for MetadataFactoryRegistry configuration " + "file: " + configurationFileLoc); } } } else { if (log.isDebugEnabled()) { log.debug("Did not find URL for MetadataFactoryRegistry configuration " + "file: " + configurationFileLoc); } } } catch (Throwable t) { if (log.isDebugEnabled()) { log.debug("The MetadataFactoryRegistry could not process the configuration file: " + configurationFileLoc + " because of the following error: " + t.toString()); } } } /** * Package protected method to allow tests to set the location * of the configuration file. * @param configFileName */ static void setConfigurationFileLocation(String configFileLoc) { configurationFileLoc = configFileLoc; loadConfigFromFile(); } private static ClassLoader getContextClassLoader(final ClassLoader classLoader) { ClassLoader cl; try { cl = (ClassLoader) AccessController.doPrivileged(new PrivilegedExceptionAction() { public Object run() throws ClassNotFoundException { return classLoader != null ? classLoader : Thread.currentThread().getContextClassLoader(); } }); } catch (PrivilegedActionException e) { if (log.isDebugEnabled()) { log.debug("Exception thrown from AccessController: " + e.getMessage(), e); } throw ExceptionFactory.makeWebServiceException(e.getException()); } return cl; } }