Unsigned Chars Over UDP Socket

I can have up to 100,000 simultaneous connections to a udp socket, which needs to be handled by separate threads. Each of the connections talk to a c program on an embedded device that sends and responds with an array of unsigned chars. Now Java does not have an unsigned char type. The closest you can use is a short. But DatagramPacket requires a byte argument:

public class Socket {
public Socket(int port) throws IOException {
new SocketThread().start();
} }
public class SocketThread extends Thread {
protected DatagramSocket socket = null;

[Code] .....

So how can I go about reading and writing unsigned chars over a udp socket?