/*

 Copyright (c) 2006, University of Tromsø

 All rights reserved.

 Redistribution and use in source and binary forms, with or without 

 modification, are permitted provided that the following conditions are met:

  * Redistributions of source code must retain the above copyright notice, this list 

    of conditions and the following disclaimer.

  * Redistributions in binary form must reproduce the above copyright notice, this 

    list of conditions and the following disclaimer in the documentation and/or other 

    materials provided with the distribution.

  * Neither the name of the University of Tromsø nor the names of its contributors may 

    be used to endorse or promote products derived from this software without specific 

    prior written permission.

 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY 

 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 

 OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 

 SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 

 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 

 TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 

 BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 

 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 

 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 

 DAMAGE.

 */

 package argos.deploy;

 import java.io.File;

 import java.net.MalformedURLException;

 import java.net.URL;

 import java.net.URLClassLoader;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import argos.metadata.ServiceMetaInfo;

 public final class JarClassloader extends URLClassLoader implements JarClassloaderMBean {

         private static final Logger logger = Logger.getLogger(JarClassloader.class.getName());

         public static final String DYNAMIC_PROXY = "DynamicProxy.jar";

         public static final String DYNAMIC_PROXY_CLASS_NAME = "argos.proxy.DynamicProxy";

         private URLClassLoader componentClassLoader;

         public JarClassloader(URL[] files) {

                 this(files, ClassLoader.getSystemClassLoader());

         }

         private JarClassloader(URL[] files, ClassLoader loader) {

                 super(new URL[]{});

                 try {

                         addURL(new URL("file:" + (new File(DYNAMIC_PROXY)).getAbsolutePath()));

                 }

                 catch(MalformedURLException e) {

                         logger.log(Level.SEVERE, "Unable to load " + DYNAMIC_PROXY + " into classpath", e);

                 }

                 componentClassLoader = new URLClassLoader(files, loader);

         }

         public static JarClassloader getInstance(ServiceMetaInfo service) {

                 return getInstance(service, null);

         }

         @Override

         public Class<?> findClass(String className) throws ClassNotFoundException {

                 if(!className.equals(DYNAMIC_PROXY_CLASS_NAME)) {

                         return componentClassLoader.loadClass(className);

                 }

                 else {

                         return super.findClass(className);

                 }

         }

         @Override

         public Class<?> loadClass(String className) throws ClassNotFoundException {

                 if(!className.equals(DYNAMIC_PROXY_CLASS_NAME)) {

                         return componentClassLoader.loadClass(className);

                 }

                 else {

                         return super.loadClass(className);

                 }

         }

         @Override

         public URL findResource(String name) {

                 if(!name.equals(DYNAMIC_PROXY_CLASS_NAME)) {

                         return componentClassLoader.findResource(name);

                 }

                 else {

                         return super.findResource(name);

                 }

         }

         @Override

         public URL getResource(String name) {

                 if(!name.equals(DYNAMIC_PROXY_CLASS_NAME)) {

                         return componentClassLoader.getResource(name);

                 }

                 else {

                         return super.getResource(name);

                 }

         }

         public static JarClassloader getInstance(ServiceMetaInfo service, ClassLoader classLoader) {

                 //Find files

                 List<File> files = new ArrayList<File>();

                 files.add(service.getTempFile());

                 for(File newFile : service.getLibraries()) {

                         files.add(newFile);

                 }

                 //Add files

                 URL[] urls = new URL[files.size()];

                 for(int i = 0; i < files.size(); i++) {

                         try {

                                 urls[i] = new URL("file:" + files.get(i).getAbsolutePath());

                         }

                         catch (MalformedURLException e) {

                                 logger.log(Level.SEVERE, "Unable to load jar into classpath: " + 

                                                 files.get(i).getAbsolutePath(), e);

                         }

                 }

                 //Create class loader

                 if(classLoader == null) {

                         return new JarClassloader(urls);

                 }

                 else {

                         return new JarClassloader(urls, classLoader);

                 }

         }

 }