/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 *
 * http://www.gnu.org/copyleft/gpl.html
 */

package com.l2dot.gameserver.util;

import java.io.DataInputStream;
import java.io.File;
import java.io.IOException;
import java.util.HashSet;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

/**
 * This is a class loader for the dynamic extensions used by DynamicExtension class.
 *
 * @version $Revision: $ $Date: $
 * @author  galun
 */
public class JarClassLoader extends ClassLoader {
    private static Logger _log = Logger.getLogger(JarClassLoader.class.getCanonicalName());
    HashSet<String> _jars = new HashSet<String>();

    public void addJarFile(String filename) {
    	_jars.add(filename);
    }

    @Override
	public Class<?> findClass(String name) throws ClassNotFoundException {
    	try {
    		byte[] b = loadClassData(name);
    		return defineClass(name, b, 0, b.length);
    	} catch (Exception e) {
    		throw new ClassNotFoundException(name);
    	}
    }

    private byte[] loadClassData(String name) throws IOException {
    	byte[] classData = null;
    	for (String jarFile : _jars) {
    		try {
    			File file = new File(jarFile);
    			ZipFile zipFile = new ZipFile(file);
    			String fileName = name.replace('.', '/') + ".class";
    			ZipEntry entry = zipFile.getEntry(fileName);
    			if (entry == null)
    				continue;
    			classData = new byte[(int)entry.getSize()];
    			DataInputStream zipStream = new DataInputStream(zipFile.getInputStream(entry));
    			zipStream.readFully(classData, 0, (int) entry.getSize());
    			break;
    		} catch (IOException e) {
    			_log.log(Level.WARNING, jarFile + ":" + e.toString(), e);
    			continue;
    		}
    	}
    	if (classData == null)
    		throw new IOException("class not found in " + _jars);
    	return classData;
    }
}

