Java tutorial
/******************************************************************************* * Copyright (c) 2006-2010 eBay Inc. 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. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 *******************************************************************************/ package org.ebayopensource.turmeric.eclipse.utils.classloader; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.net.URL; import java.net.URLClassLoader; import java.util.ArrayList; import java.util.Comparator; import java.util.List; import java.util.Set; import java.util.TreeSet; import java.util.jar.JarEntry; import java.util.jar.JarFile; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.commons.io.FileUtils; import org.osgi.framework.Bundle; /** * The Class SOAPluginClassLoader. * * @author smathew */ public class SOAPluginClassLoader extends URLClassLoader { private static final URL[] EMPTY_URLS = new URL[0]; private static final Comparator<URL> URL_COMPARATOR = new Comparator<URL>() { @Override public int compare(URL o1, URL o2) { return (o1 != null && o2 != null) ? o1.toString().compareTo(o2.toString()) : 0; } }; private Set<URL> m_jarURLs = new TreeSet<URL>(URL_COMPARATOR); private Set<URL> m_dirURLs = new TreeSet<URL>(URL_COMPARATOR); private Set<URL> m_classPathURLs = new TreeSet<URL>(URL_COMPARATOR); private List<Bundle> pluginBundles = new ArrayList<Bundle>(); private static final Logger logger = Logger.getLogger(SOAPluginClassLoader.class.getName()); /** * Instantiates a new sOA plugin class loader. * * @param name the name * @param urls the urls */ public SOAPluginClassLoader(String name, URL[] urls) { super(EMPTY_URLS); for (int i = 0; i < urls.length; i++) { File file = FileUtils.toFile(urls[i]); if (file.isDirectory()) { m_dirURLs.add(urls[i]); } else if (file.isFile()) { m_jarURLs.add(urls[i]); } } for (URL dirURL : m_dirURLs) { addURL(dirURL); } m_classPathURLs.addAll(m_jarURLs); m_classPathURLs.addAll(m_dirURLs); if (logger.isLoggable(Level.FINE)) { logger.fine("Inside soa plugin loader setM_classPathURLs: " + m_classPathURLs); } } /* (non-Javadoc) * @see java.lang.ClassLoader#loadClass(java.lang.String, boolean) */ @Override protected synchronized Class<?> loadClass(String name, boolean resolve) throws ClassNotFoundException { try { Class<?> _class = doLoadClass(name); if (_class != null) return _class; } catch (Exception e) { //oops, got some problems just ignore it. } return super.loadClass(name, resolve); } private Class<?> doLoadClass(String className) throws ClassNotFoundException { Class<?> clazz = null; try { for (Bundle pluginBundle : pluginBundles) { clazz = pluginBundle.loadClass(className); if (clazz != null) { //logger.info("loaded using bundle class loader->" // + className); return clazz; } } } catch (ClassNotFoundException classNotFoundException) { } return clazz; } /** * {@inheritDoc} */ @Override protected Class<?> findClass(String name) throws ClassNotFoundException { Class<?> loadedClass = findLoadedClass(name); if (loadedClass != null) { return loadedClass; } StringBuilder sb = new StringBuilder(name.length() + 6); sb.append(name.replace('.', '/')).append(".class"); InputStream is = getResourceAsStream(sb.toString()); if (is == null) throw new ClassNotFoundException("Class not found " + sb); try { ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] buf = new byte[1024]; int len; while ((len = is.read(buf)) >= 0) baos.write(buf, 0, len); buf = baos.toByteArray(); // define package if not defined yet int i = name.lastIndexOf('.'); if (i != -1) { String pkgname = name.substring(0, i); Package pkg = getPackage(pkgname); if (pkg == null) definePackage(pkgname, null, null, null, null, null, null, null); } baos.close(); is.close(); return defineClass(name, buf, 0, buf.length); } catch (IOException e) { throw new ClassNotFoundException(name, e); } } /** * {@inheritDoc} */ @Override public URL findResource(String resourceName) { //logger.info("resource name in findresource is " + resourceName); try { URL retUrl = null; for (Bundle pluginBundle : pluginBundles) { retUrl = pluginBundle.getResource(resourceName); if (retUrl != null) { if (logger.isLoggable(Level.FINE)) { logger.fine("found resource using bundle " + resourceName); } return retUrl; } } } catch (Exception exception) { } for (URL url : m_jarURLs) { try { File file = FileUtils.toFile(url); JarFile jarFile; jarFile = new JarFile(file); JarEntry jarEntry = jarFile.getJarEntry(resourceName); if (jarEntry != null) { SOAToolFileUrlHandler handler = new SOAToolFileUrlHandler(jarFile, jarEntry); URL retUrl = new URL("jar", "", -1, new File(jarFile.getName()).toURI().toURL() + "!/" + jarEntry.getName(), handler); handler.setExpectedUrl(retUrl); return retUrl; } } catch (IOException e) { e.printStackTrace(); // KEEPME } } return super.findResource(resourceName); } /** * Gets the plugin bundles. * * @return the plugin bundles */ public List<Bundle> getPluginBundles() { return pluginBundles; } /** * Sets the plugin bundles. * * @param pluginBundles the new plugin bundles */ public void setPluginBundles(List<Bundle> pluginBundles) { this.pluginBundles = pluginBundles; } /* (non-Javadoc) * @see java.net.URLClassLoader#getURLs() */ @Override public URL[] getURLs() { return m_classPathURLs.toArray(new URL[0]); } /** * Gets the m_class path ur ls. * * @return the m_class path ur ls */ public Set<URL> getM_classPathURLs() { return m_classPathURLs; } /** * Sets the m_class path ur ls. * * @param pathURLs the new m_class path ur ls */ public void setM_classPathURLs(Set<URL> pathURLs) { if (logger.isLoggable(Level.FINE)) { logger.fine("Inside soa plugin loader setM_classPathURLs: " + pathURLs); } m_classPathURLs = pathURLs; } }