servermet.java

JMule是一个基于Java开发

/*
 *  JMule - Java file sharing client
 *  Copyright (C) 2007-2008 JMule team ( [e-mail] / http://jmule.org )
 *
 *  Any parts of this program derived from other projects, or contributed
 *  by third-party developers are copyrighted by their respective authors.
 *
 *  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
 *  of the License, 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 */
package org.jmule.core.edonkey.metfile;

import static org.jmule.core.edonkey.E2DKConstants.SERVERLIST_VERSION;

import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import org.jmule.core.edonkey.impl.Server;
import org.jmule.core.edonkey.packet.tag.Tag;
import org.jmule.core.edonkey.packet.tag.TagList;
import org.jmule.core.edonkey.packet.tag.TagReader;
import org.jmule.util.Convert;
import org.jmule.util.Misc;


/**
 * <table cellpadding="0" border="1" cellspacing="0" width="70%">
 * <tbody>
 *   <tr>
 *     <td>Name</td>
 *     <td>Size in bytes</td>
 *     <td>Default value</td>
 *   </tr>
 *   <tr>
 *     <td>File header</td>
 *     <td>1</td>
 *     <td>0xE0</td>
 *   </tr>
 *   <tr>
 *     <td>Server count</td>
 *     <td>4</td>
 *     <td></td>
 *   </tr>
 *   <tr>
 *     <td>Servers</td>
 *     <td>Varies</td>
 *     <td></td>
 *   </tr>
 * </tbody>
 * </table>
 * <br>
 * Server Data Block :
 *  
 * <table cellpadding="0" border="1" cellspacing="0" width="70%">
 * <tbody>
 *   <tr>
 *     <td>Name</td>
 *     <td>Size in bytes</td>
 *   </tr>
 *   <tr>
 *     <td>Server IP</td>
 *     <td>4</td>
 *   </tr>
 *   <tr>
 *     <td>Server Port</td>
 *     <td>2</td>
 *   </tr>
 *   <tr>
 *     <td>Tag count</td>
 *     <td>4</td>
 *   </tr>
 *   <tr>
 *     <td>Tag list</td>
 *     <td>variable</td>
 *   </tr>
 * </tbody>
 * </table>
 *
 * @author binary256
 * @version $$Revision: 1.6 $$
 * Last changed by $$Author: binary256_ $$ on $$Date: 2008/09/27 13:05:11 $$
 */
public class ServerMet extends MetFile {
	
	private List<Server> serverList;

	
	public ServerMet(String fileName) throws ServerMetException  {
		super(fileName);
		if (fileChannel==null) throw new ServerMetException("Can't open server.met file");
	}
	
	public void load() throws ServerMetException {
		try {
			fileChannel.position(0);
		} catch (IOException e) {
			throw new ServerMetException("Failed to move at position 0 in server.met");
		}
		
		byte serverListFormat;
		serverList = new LinkedList<Server>();
		ByteBuffer data;
		
		data = Misc.getByteBuffer(1);
			
		try {
				
			fileChannel.read(data); 
			
			serverListFormat = data.get(0);

			//if (serverListFormat != SERVERLIST_VERSION)
			//	throw new ServerMetException("Unsupported server met file");
	
			data = Misc.getByteBuffer(4);
			fileChannel.read(data);
			long serverCount = Convert.intToLong(data.getInt(0));
			
			for(long i = 0; i < serverCount; i++) {
				Server server = readServer();
				serverList.add(server);
			}
			
		 } catch(Throwable exception) {
			 
			 throw new ServerMetException("Unknown file format");
			 
		 }
	}
	
	public void store() throws ServerMetException {
		try {
			fileChannel.close();
			file.delete();
			fileChannel = new RandomAccessFile(file,"rws").getChannel();
			fileChannel.position(0);
			ByteBuffer data;
		
			data = Misc.getByteBuffer(1);
			data.put(SERVERLIST_VERSION);
			data.position(0);
			fileChannel.write(data);
				
			long count = 0;
			
			for(Server server : serverList) 
				if (server.isStatic()) count++;
			
			setServersCount(count);
		
			for(Server server : serverList) 
				if (server.isStatic())
					writeServer(server);
		
		}
	
		catch(IOException ioe) {
		  
		  throw new ServerMetException("IOException : " + ioe);
		}
		
	}
	
	public void appendFile(Server appendServer) throws IOException {
		fileChannel.position(0);
		long fileCount = getServersCount();
		fileCount++;
		setServersCount(fileCount);
		
		fileChannel.position(fileChannel.size());
		writeServer(appendServer);
	}
	
	/**
	 * Obtain server count from fileChannel.
	 * @param fileChannel
	 * @return
	 * @throws IOException
	 */
	private long getServersCount() throws IOException {
		ByteBuffer data;
		data = Misc.getByteBuffer(4);
		fileChannel.position(1);
		fileChannel.read(data);
		return Convert.intToLong(data.getInt(0));
	}
	
	/**
	 * Set server count in fileChannel.
	 * @param fileChannel
	 * @param serverCount
	 * @throws IOException
	 */
	private void setServersCount(long serverCount) throws IOException {
		ByteBuffer data = Misc.getByteBuffer(4);
		data.putInt(Convert.longToInt(serverCount));
		data.position(0);
		fileChannel.position(1);
		fileChannel.write(data);
	}
	
	private Server readServer() throws IOException {
		ByteBuffer data;
		
		TagList tagList = new TagList();
		//Read server IP
		data = Misc.getByteBuffer(4);
		fileChannel.read(data);
		
		String remonteAddress = Convert.IPtoString(data.array());
		
		//Read server port 
		data = Misc.getByteBuffer(2);
		fileChannel.read(data);
		
		int remontePort = (Convert.shortToInt(data.getShort(0)));
		
		//Read TagList count
		data = Misc.getByteBuffer(4);
		fileChannel.read(data);
		
		int tagCount = data.getInt(0);
						
		//Load tags....
		for(int j = 0; j<tagCount; j++) {
			Tag tag = TagReader.readTag(fileChannel);
			if (tag != null)
				tagList.addTag(tag);
		}
		
		Server server = new Server(remonteAddress,remontePort,tagList);
		server.setStatic(true);
		return server;
		
	}
	
	/**
	 * Write one Server object in fileChannel at current position.
	 * @param fileChannel
	 * @param server
	 * @throws IOException
	 */
	private void writeServer(Server server) throws IOException {
		ByteBuffer data;
		data = Misc.getByteBuffer(4);
		
		data.put(Convert.stringIPToArray(server.getAddress()));
		data.position(0);
		fileChannel.write(data);
		
		data = Misc.getByteBuffer(2);
		data.putShort((short) server.getPort());
		data.position(0);
		fileChannel.write(data);
		
		data = Misc.getByteBuffer(4);
		data.putInt(server.getTagList().getTagCount());
		data.position(0);
		fileChannel.write(data);
		
		Collection<Tag> tagList = server.getTagList().getTags();
		
		for(Tag tag : tagList) {
			data = Misc.getByteBuffer(tag.getData().length);
			data.put(tag.getData());
			data.position(0);
			fileChannel.write(data);
		}
		
	  }

	public List<Server> getServerList() {
		
		return serverList;
	}

	public void setServerList(List<Server> serverList) {
		
		this.serverList = serverList;
	}


}