server/XMLReader/UDPReader.java

import java.io.*;
import java.net.*;
import java.util.*;

// This class contains the main method to be run by
// the filter children.  It harvests UDP traffic
//
//
public class UDPReader {

    public static void main(String[] args) throws IOException {

        // default UDP listening port.
        int port = 4589;
        final int packetSizeLimit = 8192;

        // Allow the user to choose their own port number.
        if (args.length == 1){
            try {
                port = new Integer(args[0]).intValue();
            }
            catch (Exception e){
                // If something went wrong, use the default again.
                port = 4589;
            }
        }

        DatagramSocket socket = null;
        try {
            socket = new DatagramSocket(port);
        }
        catch (BindException e){
            System.out.println("Some other process is already listening on port "+port+".");
            System.out.println("Please specify another port number on the command line.");
            System.exit(0);
        }
        
        System.out.println("UDPReader ready and listening for UDP packets on port "+port);

        boolean running = true;
        while (running){
            try {
                byte[] buf = new byte[packetSizeLimit];
                // receive request
                DatagramPacket packet = new DatagramPacket(buf, buf.length);
                socket.receive(packet);
                UDPReaderThread thread = new UDPReaderThread(packet);
                thread.run();
            }
            catch (IOException e) {
                System.out.println("An exception occured in the UDPReader!");
                e.printStackTrace();
            }
        }
        socket.close();
    }
}
Revision:	1.3
Committed:	Fri Nov 17 15:25:48 2000 UTC (24 years ago) by pjm2
Branch:	MAIN
Changes since 1.2:	+10 -1 lines
Log Message:	Wrapped the DatagramSocket part in a try { } so that a warning is given when some other process is already listening on the same port.
#	User	Rev	Content
1	pjm2	1.1	import java.io.*;
2			import java.net.*;
3			import java.util.*;
4
5			// This class contains the main method to be run by
6			// the filter children. It harvests UDP traffic
7			//
8			//
9			public class UDPReader {
10
11			public static void main(String[] args) throws IOException {
12
13	pjm2	1.2	// default UDP listening port.
14			int port = 4589;
15			final int packetSizeLimit = 8192;
16	pjm2	1.1
17	pjm2	1.2	// Allow the user to choose their own port number.
18			if (args.length == 1){
19			try {
20			port = new Integer(args[0]).intValue();
21			}
22			catch (Exception e){
23			// If something went wrong, use the default again.
24			port = 4589;
25			}
26			}
27
28	pjm2	1.3	DatagramSocket socket = null;
29			try {
30			socket = new DatagramSocket(port);
31			}
32			catch (BindException e){
33			System.out.println("Some other process is already listening on port "+port+".");
34			System.out.println("Please specify another port number on the command line.");
35			System.exit(0);
36			}
37
38	pjm2	1.2	System.out.println("UDPReader ready and listening for UDP packets on port "+port);
39
40			boolean running = true;
41			while (running){
42			try {
43			byte[] buf = new byte[packetSizeLimit];
44	pjm2	1.1	// receive request
45	pjm2	1.2	DatagramPacket packet = new DatagramPacket(buf, buf.length);
46			socket.receive(packet);
47			UDPReaderThread thread = new UDPReaderThread(packet);
48			thread.run();
49			}
50			catch (IOException e) {
51			System.out.println("An exception occured in the UDPReader!");
52			e.printStackTrace();
53			}
54	pjm2	1.1	}
55			socket.close();
56			}
57			}