public byte[] toByteArray(){
		ByteArrayOutputStream bos = new ByteArrayOutputStream();
		ObjectOutput out = null;
		try {
			out = new ObjectOutputStream(bos);   
			out.writeObject(this);
			return bos.toByteArray();
		}catch(Exception e){e.printStackTrace(); return null;} 
		finally {
			try {if (out != null) {out.close();}} catch (IOException ex) {}
			try {bos.close();} catch (IOException ex) {}
		}
	}