/* * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  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 Sun Microsystems 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. */ import java.net.URL;import java.net.URLClassLoader;import java.net.JarURLConnection;import java.lang.reflect.Method;import java.lang.reflect.Modifier;import java.lang.reflect.InvocationTargetException;import java.util.jar.Attributes;import java.io.IOException;/** * A class loader for loading jar files, both local and remote. */class JarClassLoader extends URLClassLoader {    private URL url;    /**     * Creates a new JarClassLoader for the specified url.     *     * @param url the url of the jar file     */    public JarClassLoader(URL url) {        super(new URL[] { url });        this.url = url;    }    /**     * Returns the name of the jar file main class, or null if     * no "Main-Class" manifest attributes was defined.     */    public String getMainClassName() throws IOException {        URL u = new URL("jar", "", url + "!/");        JarURLConnection uc = (JarURLConnection)u.openConnection();        Attributes attr = uc.getMainAttributes();        return attr != null ? attr.getValue(Attributes.Name.MAIN_CLASS) : null;    }    /**     * Invokes the application in this jar file given the name of the     * main class and an array of arguments. The class must define a     * static method "main" which takes an array of String arguemtns     * and is of return type "void".     *     * @param name the name of the main class     * @param args the arguments for the application     * @exception ClassNotFoundException if the specified class could not     *            be found     * @exception NoSuchMethodException if the specified class does not     *            contain a "main" method     * @exception InvocationTargetException if the application raised an     *            exception     */    public void invokeClass(String name, String[] args)        throws ClassNotFoundException,               NoSuchMethodException,               InvocationTargetException    {        Class c = loadClass(name);        Method m = c.getMethod("main", new Class[] { args.getClass() });        m.setAccessible(true);        int mods = m.getModifiers();        if (m.getReturnType() != void.class || !Modifier.isStatic(mods) ||            !Modifier.isPublic(mods)) {            throw new NoSuchMethodException("main");        }        try {            m.invoke(null, new Object[] { args });        } catch (IllegalAccessException e) {            // This should not happen, as we have disabled access checks        }    }}