/* Angelehnt an Kurose/Ross Computernetzwerke (bis 5e Java, ab 6e Python) */

package socket;

import java.net.*;

class Server1 {
	public static void main(String args[]) throws Exception {
		int port = 36037;

		DatagramSocket serverSocket = new DatagramSocket(port);

		byte[] receiveData = new byte[1024];
		byte[] sendData = new byte[1024];
		String message;
		String modifiedMessage;

		System.out.println("Server1 gestartet. Warte auf eingehende Requests...");
		
		while (true) {
			DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
			serverSocket.receive(receivePacket);
			message = new String(receivePacket.getData(), 0, receivePacket.getLength());

			InetAddress clientAddress = receivePacket.getAddress();
			int clientSrcPort = receivePacket.getPort();

			System.out.println("Request von Client1 " + clientAddress + ":" + clientSrcPort + " empfangen. Erzeuge und sende Antwort...");
			
			if (message.equals("exit"))
			{
				break;
			}
			
			modifiedMessage = message.toUpperCase();
			sendData = modifiedMessage.getBytes();
			DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, clientAddress, clientSrcPort);
			serverSocket.send(sendPacket);
		}
		serverSocket.close();
	}
}