Glassfish example source code file (ClassPathManager.java)

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Java - Glassfish tags/keywords

classloader, classnotfoundexception, classpathmanager, illegalaccessexception, illegalaccessexception, invocationtargetexception, invocationtargetexception, io, malformedurlexception, net, network, reflection, string, string, uri, urisyntaxexception, url, url

The Glassfish ClassPathManager.java source code

/*
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 *
 * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
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 * recipient has the option to distribute your version of this file under
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 * and therefore, elected the GPL Version 2 license, then the option applies
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 */

package org.glassfish.appclient.client.jws.boot;

import java.io.File;
import java.lang.reflect.InvocationTargetException;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLClassLoader;

/**
 * Abstract superclass of classes that manage the class path needed to run
 * the Java Web Start-aware ACC.
 *<p>
 * Some details vary among releases of the Java runtime  This abstract class
 * and its concrete implementation subclasses isolate those dependencies.
 *
 * @author tjquinn
 */
public abstract class ClassPathManager {
    
    public static final String PERSISTENCE_JAR_CLASSES = 
            "org.apache.derby.client.ClientDataSourceFactory," /* derbyclient.jar */ +
            "persistence.antlr.ActionElement," /* toplink-essentials */ +
            "org.netbeans.modules.dbschema.ColumnElement," /* dbschema */
            ;

    /** instance of appropriate type of class path manager, depending on the Java runtime version */
    private static ClassPathManager mgr = null;
    
    private final boolean keepJWSClassLoader;
    
    /**
     *Returns the appropriate type of ClassPathManager.
     *@return an instance of the correct implementation subclass class path manager
     */
    public static ClassPathManager getClassPathManager(boolean keepJWSClassLoader) {
        if (mgr == null) {
            ClassLoader loader = Thread.currentThread().getContextClassLoader();
            /*
             *Distinguish between 1.6 and earlier by seeing if the curent
             *class loader - the JNLP class loader - is also a URLClassLoader
             *or not.
             */
            if (loader instanceof URLClassLoader) {
                mgr = new ClassPathManager16(loader, keepJWSClassLoader);
            } else {
                mgr = new ClassPathManager15(loader, keepJWSClassLoader);
            }
        }
        return mgr;
    }
    
    /** the JNLP class loader active during the instantiation of this mgr */
    private ClassLoader jnlpClassLoader = null;

    /**
     *Returns a new instance of the manager.
     *@param loader the class loader provided by Java Web Start
     */
    protected ClassPathManager(ClassLoader loader, boolean keepJWSClassLoader) {
        jnlpClassLoader = loader;
        this.keepJWSClassLoader = keepJWSClassLoader;
    }
    
    protected boolean keepJWSClassLoader() {
        return keepJWSClassLoader;
    }
    
    protected ClassLoader getJnlpClassLoader() {
        return jnlpClassLoader;
    }
    
    /**
     *Locates the URI for the JAR containing the specified class
     *@param className the name of the class to be located
     *@return the URI for the JAR file containing the class of interest
     */
    public URI locateClass(String className) throws 
            IllegalAccessException, 
            InvocationTargetException, 
            MalformedURLException, 
            URISyntaxException, ClassNotFoundException {
        String resourceName = classNameToResourceName(className);
        URL classURL = locateResource(resourceName);
        File f = findContainingJar(classURL);
        if (f == null) {
            /*
             *Could not locate the class we expected.
             */
            throw new ClassNotFoundException(className + "->" + resourceName);
        }
        return f.toURI();
    }

    /**
     *Returns the appropriate parent class loader for the ACC.
     *@return the correct class loader instance 
     */
    public abstract ClassLoader getParentClassLoader();

    /*
     *Returns the jar that contains the specified resource.
     *@param resourceURL URL to look for
     *@return File object for the jar or directory containing the entry
     */
    public abstract File findContainingJar(URL resourceURL) throws 
            IllegalArgumentException, 
            URISyntaxException, 
            MalformedURLException, 
            IllegalAccessException, 
            InvocationTargetException;

    /**
     *Returns the Java Web Start-provided class loader recorded when the
     *class path manager was created.
     *@return the Java Web Start class loader
     */
    protected ClassLoader getJNLPClassLoader() {
        return jnlpClassLoader;
    }
    
    /**
     *Converts a class name to a resource name.
     *@param className the name of the class of interest in x.y.z format
     *@return the resource name in x/y/z.class format
     */
    protected String classNameToResourceName(String className) {
        return className.replace(".", "/") + ".class";
    }

    /**
     *Finds a resource using the class's class loader.
     *@param resourceName the class to find
     *@return URL for the resource; null if not found
     */
    protected URL locateResource(String resourceName) {
        URL resourceURL = getClass().getClassLoader().getResource(resourceName);
        return resourceURL;
    }
     
    /**
     *Reports URLs for the locally-cached copies of the JARs downloaded by
     *Java Web Start needed for the ACC's class path and policy settings.
     *@return array of URLs, one entry for each downloaded JAR
     */
    public URL[] locateDownloadedJars() throws 
            ClassNotFoundException, 
            URISyntaxException, 
            NoSuchMethodException, 
            IllegalAccessException, 
            InvocationTargetException, 
            MalformedURLException {
        /*
         *For each downloaded unsigned app client jar, get a URL that locates
         *it and add the URL to the list.
         *
         *This set of values should be automated on the server side and 
         *communicated via a property setting in the JNLP document so 
         *any changes in the list of downloaded files does not need to be made
         *there and here.  
         */
        String probeClassNames = System.getProperty("com.sun.aas.jar.probe.class.names",
                "com.sun.enterprise.appclient.jws.boot.JWSACCMain," /* appserv-jwsacc */ +
                "com.sun.enterprise.appclient.Main," /* appserv-rt */ +
                "com.sun.jdo.api.persistence.enhancer.ByteCodeEnhancer," /* appserv-cmp */ +
                "com.sun.enterprise.admin.servermgmt.DomainConfig," /* appserv-admin */ +
                "com.sun.enterprise.deployment.client.DeploymentClientUtils," /* appserv-deployment-client */ +
                "javax.ejb.EJB," /* javaee */ +
                "javax.security.auth.message.module.ServerAuthModule," /* jmac-api */ +
                "com.sun.appserv.management.ext.logging.LogAnalyzer," /* appserv-ext */ + 
                "com.sun.mail.iap.Argument," /* mail */ +
                "com.sun.activation.viewers.ImageViewer," /* activation */ +
                "com.sun.xml.ws.api.server.WSEndpoint," /* webservices-rt */ +
                "com.sun.tools.ws.wsdl.parser.W3CAddressingExtensionHandler," /* webservices-tools */ +
                "com.sun.jms.spi.xa.JMSXAConnection," /* imqjmsra */ +
                "com.sun.jndi.fscontext.FSContext" /* fscontext */
                );

        return locateJARs(probeClassNames);
    }        
    
    public URL[] locateJARs(String classNamesString) throws 
            IllegalAccessException, InvocationTargetException, 
            MalformedURLException, URISyntaxException, ClassNotFoundException {
        
        String [] classNames = classNamesString.split(",");

        /*
         *For each class name, find the jar that contains it by getting a URL
         *to the class and then using that URL to find the jar.
         */
        URL [] urls = new URL[classNames.length];
        int nextURL = 0;

        for (String className : classNames) {
            URI jarFileURI = locateClass(className);
            URL url = jarFileURI.toURL();
            urls[nextURL++] = url;
        }
        return urls;
    }
    
    public URL[] locatePersistenceJARs() throws 
            IllegalAccessException, InvocationTargetException, 
            MalformedURLException, URISyntaxException, ClassNotFoundException {
        return locateJARs(PERSISTENCE_JAR_CLASSES);
    }
}