movinopacket.java

一个不错的多媒体传输程序

/*
 * Movino J2ME Client
 * Copyright (C) 2007  Johannes Berg
 * 
 * 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.movino.connection;

import java.io.ByteArrayOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;

public class MovinoPacket {

	//these are used for outgoing traffic
	public static final int MOVINO_DATA_GARBAGE = 0;
	public static final int MOVINO_DATA_YUV_FRAME = 1;
	public static final int MOVINO_DATA_PCM_AUDIO = 2;
	public static final int MOVINO_DATA_JPEG_HEADER = 3;
	public static final int MOVINO_DATA_JPEG_DATA = 4;
	public static final int MOVINO_DATA_MULAW_AUDIO = 5;
	public static final int MOVINO_DATA_AMR_AUDIO = 6;
	public static final int MOVINO_DATA_START_MTU_MEASUREMENT = 7;
	public static final int MOVINO_DATA_STOP_MTU_MEASUREMENT = 8;
	public static final int MOVINO_DATA_VIDEO_FILE = 9;
	public static final int MOVINO_DATA_MPEG_FRAME = 10;
	public static final int MOVINO_DATA_VIDEO_CHUNK = 11;
	public static final int MOVINO_DATA_THEORA_HEADER = 12;
	public static final int MOVINO_DATA_THEORA_FRAME = 13;
	public static final int MOVINO_DATA_HANDSHAKE = 14;
	public static final int MOVINO_DATA_STREAM_INFO = 15;
	public static final int MOVINO_DATA_STREAM_CLOSED = 16;

	//these are used for incoming traffic
	public static final int MOVINO_REPLY_MTU_SIZE = 1;
	public static final int MOVINO_REPLY_HANDSHAKE = 2;
	public static final int MOVINO_REPLY_PING = 3;

	
	private int packetType;
	
	public MovinoPacket(int type){
		packetType = type;
	}
	
	public int getType(){
		return packetType;
	}
	
	public final void writePacket(DataOutputStream out) throws IOException{
		ByteArrayOutputStream bout = new ByteArrayOutputStream();
		DataOutputStream buffer_stream = new DataOutputStream(bout);
		buffer_stream.writeByte(packetType);
		buffer_stream.writeInt(0);
		
		writePacketData(buffer_stream);
		byte[] data = bout.toByteArray();
		
		int len = data.length-5;
		data[1] = (byte)((len>>24)&0xff);
		data[2] = (byte)((len>>16)&0xff);
		data[3] = (byte)((len>>8)&0xff);
		data[4] = (byte)(len&0xff);
		out.write(data);
		
		//out.writeByte(packetType);
		//out.writeInt(getPacketLength());
		//writePacketData(out);
	}
	
	public void writePacketData(DataOutputStream out) throws IOException{
	}
	/*public int getPacketLength(){
		return 0;
	}*/
	
	public static MovinoPacket readPacket(DataInputStream in) throws IOException{
		int type = in.readByte();
		int len = in.readInt();
		
		MovinoPacket packet = null;
		
		switch(type){
			case MOVINO_REPLY_HANDSHAKE:
				packet = new HandShakePacket(in,len);
				break;
			case MOVINO_REPLY_PING:
				packet = new PingPacket(in,len);
				break;
			default:
				int skip_len = len;
				while(skip_len>0) skip_len -= in.skip(skip_len);
				packet = new MovinoPacket(type);
				break;
		}
		
		return packet;
	}
}