sysdis-project/command-terminal/CommandTerminal/src/commandterminal/CommandTerminal.java

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package commandterminal;

import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.nio.ByteBuffer;

/**
 *
 * @author lmascaro
 */
public class CommandTerminal {
    
    private final static int SGCA_MULTICAST_PORT = 4446;
    private final static String SCGA_MULTICAST_ADDRESS = "224.0.0.3";

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args){
        
    	/*
    	 * Handshake
    	 */
    	
    	try {
			DatagramSocket socket = new DatagramSocket();
			ByteBuffer buf = ByteBuffer.allocate(21);
			buf.clear();
			buf.put((byte)(0x01|0x02));
			
			DatagramPacket payload = new DatagramPacket(buf.array(),buf.array().length,InetAddress.getByName(SCGA_MULTICAST_ADDRESS),SGCA_MULTICAST_PORT);
			socket.send(payload);
			
			socket.receive(payload);
			
			buf = ByteBuffer.wrap(payload.getData());
			
			if(buf.get() == 3){
				System.out.println("--Connection request successful");
				byte address[] = new byte[15];
				buf = buf.get(address,0,15);
				String addressString = new String(address);
				InetAddress sgcaAddress = InetAddress.getByName(addressString);
				//emulate an unsigned short
				char cast = buf.getChar();
				int port = (int) cast;
				System.out.println("----Address : "+sgcaAddress.getHostAddress());
				System.out.println("----Port : "+port);
			}
			
    	} catch ( IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
        
        
    }
    
}