Quadcap Embeddable Server

com/quadcap/http/server22/WebClassLoader.java

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package com.quadcap.http.server22;

/* Copyright 1999 - 2003 Quadcap Software.  All rights reserved.
 *
 * This software is distributed under the Quadcap Free Software License.
 * This software may be used or modified for any purpose, personal or
 * commercial.  Open Source redistributions are permitted.  Commercial
 * redistribution of larger works derived from, or works which bundle
 * this software requires a "Commercial Redistribution License"; see
 * http://www.quadcap.com/purchase.
 *
 * Redistributions qualify as "Open Source" under  one of the following terms:
 *   
 *    Redistributions are made at no charge beyond the reasonable cost of
 *    materials and delivery.
 *
 *    Redistributions are accompanied by a copy of the Source Code or by an
 *    irrevocable offer to provide a copy of the Source Code for up to three
 *    years at the cost of materials and delivery.  Such redistributions
 *    must allow further use, modification, and redistribution of the Source
 *    Code under substantially the same terms as this license.
 *
 * Redistributions of source code must retain the copyright notices as they
 * appear in each source code file, these license terms, and the
 * disclaimer/limitation of liability set forth as paragraph 6 below.
 *
 * Redistributions in binary form must reproduce this Copyright Notice,
 * these license terms, and the disclaimer/limitation of liability set
 * forth as paragraph 6 below, in the documentation and/or other materials
 * provided with the distribution.
 *
 * The Software is provided on an "AS IS" basis.  No warranty is
 * provided that the Software is free of defects, or fit for a
 * particular purpose.  
 *
 * Limitation of Liability. Quadcap Software shall not be liable
 * for any damages suffered by the Licensee or any third party resulting
 * from use of the Software.
 */

import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Vector;

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.IOException;

import java.net.URL;

import com.quadcap.io.dir.Directory;
import com.quadcap.io.dir.Entry;

import com.quadcap.io.IO;

import com.quadcap.util.Debug;


/**
 * This class implements a JSP class loader
 *
 * @author Stan Bailes
 */
public class WebClassLoader extends ClassLoader {
    File                                tmpDir;
    Directory                           root;
    Vector                              jars    = new Vector();

    public WebClassLoader(Directory root, File tmpDir) {
        super();
        this.tmpDir = tmpDir;
        this.root = root;
    }

    public Class loadClass(String name) throws ClassNotFoundException {
        return loadClass(name, true);
    }

//-    //#ifdef JDK11
//-    Hashtable                        cache = new Hashtable();
//-
//-    public Class loadClass(String name, boolean resolve) 
//-     throws ClassNotFoundException 
//-    {
//-     Class c = (Class)cache.get(name);
//-     if (c == null) {
//-         c = findClass(name);
//-         cache.put(name, c);
//-     }
//-     if (resolve)
//-         resolveClass(c);
//-     return c;
//-    }
//-
    //#endif

    public Class findClass(String name) throws ClassNotFoundException {
        //#ifdef DEBUG
        if (Trace.level() > 1) {
            Debug.println("WebClassLoader[" + root +
                          "].findClass(" + name + ")");
        }
        //#endif
        byte[] b = loadClassData(name);
        return defineClass(name, b, 0, b.length,
                           this.getClass().getProtectionDomain());
    }

    public URL findResource(String name) {
        URL url = null;
        try {
            String fileName = "WEB-INF/classes" + name;
            url = root.getURL(fileName);
            if (url == null) {
                for (int i = 0; url == null && i < jars.size(); i++) {
                    Directory d = (Directory)jars.elementAt(i);
                    url = d.getURL(name);
                }
            }
        } catch (Throwable t) {
            url = null;
        }
        return url;
    }

    private byte[] loadClassData(String name) throws ClassNotFoundException {
        try {
            Entry classFile = locateClassFile(name);
            byte[] b = new byte[(int)(classFile.getSize())];
            InputStream f = classFile.getInputStream();
            IO.readFully(f, b);
            f.close();
            return b;
        } catch (IOException e) {
            throw new ClassNotFoundException("error loading class: " + 
                                             e.toString());
        }
    }

    final Entry locateClassFile(String name) throws ClassNotFoundException {
        String className = name.replace('.', '/') + ".class";
        String fileName = "WEB-INF/classes/" + className;
        Entry classFile = root.getEntry(fileName);
        if (classFile == null) {
            for (int i = 0; classFile == null && i < jars.size(); i++) {
                Directory d = (Directory)jars.elementAt(i);
                classFile = d.getEntry(className);
            }
        }
        if (classFile == null) {
            throw new ClassNotFoundException("not found: " + name);
        }
        return classFile;
    }

    static int tmpCount                 = 0;

    public String getClassPath() {
        StringBuffer sb = new StringBuffer();
        String delim = System.getProperty("path.separator");
        for (int i = 0; i < jars.size(); i++) {
            Directory d = (Directory)jars.elementAt(i);
            if (i > 0) sb.append(delim);
            sb.append(d.getRootPath());
        }
        return sb.toString();
    }
    
    final void init() throws IOException {
        Enumeration e = root.entries();
        Directory classes = null;
        File tmpClasses = null;
        while (e.hasMoreElements()) {
            String path = e.nextElement().toString();
            if (path.startsWith("WEB-INF/lib/") && path.endsWith(".jar")) {
                Directory d = null;
                String realPath = root.getRealPath(path);
                if (realPath == null) {
                    Entry entry = root.getEntry(path);
                    InputStream is = entry.getInputStream();
                    File out;
                    try {
                        out = new File(tmpDir,
                                       "tmp" + (tmpCount++) + ".jar");
                        FileOutputStream os = new FileOutputStream(out);
                        try {
                            IO.copyStream(is, os);
                        } finally {
                            os.close();
                        }
                    } finally {
                        is.close();
                    }
                    d = Directory.getDirectory(out);
                } else {
                    d = Directory.getDirectory(new File(realPath));
                }
                jars.addElement(d);
            } else if (path.startsWith("WEB-INF/classes")) {
                if (classes == null) {
                    String realPath = root.getRealPath("WEB-INF/classes");
                    if (realPath == null) {
                        tmpClasses = new File(tmpDir, "classes");
                        tmpClasses.mkdirs();
                        classes = Directory.getDirectory(tmpClasses);
                    } else {
                        classes = Directory.getDirectory(new File(realPath));
                    }
                    jars.addElement(classes);
                }
                if (tmpClasses != null) {
                    String subPath =
                        path.substring("WEB-INF/classes/".length());
                    if (subPath.length() > 0) {
                        subPath = subPath.replace('/', File.separatorChar);
                        Entry entry = root.getEntry(path);
                        File out = new File(tmpClasses, subPath);
                        if (entry.isDirectory()) {
                            out.mkdir();
                        } else {
                            InputStream is = entry.getInputStream();
                            try {
                                FileOutputStream os =
                                    new FileOutputStream(out);
                                try {
                                    IO.copyStream(is, os);
                                } finally {
                                    os.close();
                                }
                            } finally {
                                is.close();
                            }
                        }
                    }
                }
            }
        }
    }
}