ByteArrayOutputStream baos=new ByteArrayOutputStream();
DataOutputStream dos=new DataOutputStream(baos);
try {
dos.writeByte(1);
dos.writeShort(1);
dos.writeInt(1);
dos.writeUTF("aaa");
byte[] info=baos.toByteArray();
socket.writeUtf(info);
dos.close();
baos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}