Java tutorial
/************************************************************************************** * Copyright (c) Jonas Bonr, Alexandre Vasseur. All rights reserved. * * http://aspectwerkz.codehaus.org * * ---------------------------------------------------------------------------------- * * The software in this package is published under the terms of the LGPL license * * a copy of which has been included with this distribution in the license.txt file. * **************************************************************************************/ import java.io.InputStream; import java.net.URL; /** * Utility methods dealing with the context class loader. Fail-over is provided to the default class loader. * * @author <a href="mailto:jboner@codehaus.org">Jonas Bonr </a> */ public final class ContextClassLoader { /** * Loads a class starting from the given class loader (can be null, then use default class loader) * * @param loader * @param name of class to load * @return * @throws ClassNotFoundException */ public static Class forName(final ClassLoader loader, final String name) throws ClassNotFoundException { Class klass = null; if (loader != null) { klass = Class.forName(name, false, loader); } else { klass = Class.forName(name, false, ClassLoader.getSystemClassLoader()); } return klass; } /** * Loads a class from the context class loader or, if that fails, from the default class loader. * * @param name is the name of the class to load. * @return a <code>Class</code> object. * @throws ClassNotFoundException if the class was not found. */ public static Class forName(final String name) throws ClassNotFoundException { Class cls = null; try { cls = Class.forName(name, false, Thread.currentThread().getContextClassLoader()); } catch (Exception e) { cls = Class.forName(name); } return cls; } /** * Loads a resource from the context class loader or, if that fails, from the default class loader. * * @param name is the name of the resource to load. * @return a <code>URL</code> object. */ public static URL loadResource(final String name) { try { return Thread.currentThread().getContextClassLoader().getResource(name); } catch (Exception e) { return ClassLoader.class.getClassLoader().getResource(name); } } // /** // * Loads a resource from the context class loader or, if that fails, from the default class loader, as stream // * // * @param name is the name of the resource to load. // * @return a <code>InputStream</code> object. // */ // public static InputStream getResourceAsStream(final String name) { // InputStream stream = null; // ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader(); // if (contextClassLoader != null) { // stream = contextClassLoader.getResourceAsStream(name); // } // if (stream == null) { // ClassLoader classLoader = ClassLoader.class.getClassLoader(); // if (classLoader != null) { // stream = classLoader.getResourceAsStream(name); // } // } // return stream; // } /** * Returns the context class loader. * * @return the context class loader */ public static ClassLoader getLoader() { ClassLoader loader = Thread.currentThread().getContextClassLoader(); if (loader == null) { loader = ClassLoader.class.getClassLoader(); } return loader; } }