| 3 |
|
import java.util.*; |
| 4 |
|
|
| 5 |
|
// This class contains the main method to be run by |
| 6 |
< |
// the filter children. It harvests UDP traffic |
| 6 |
> |
// the filter children. It harvests UDP traffic. |
| 7 |
|
// |
| 8 |
|
// |
| 9 |
< |
public class UDPReader { |
| 9 |
> |
public class UDPReader extends Thread{ |
| 10 |
|
|
| 11 |
< |
public static void main(String[] args) throws IOException { |
| 11 |
> |
// It is normal to use this constructor in preference |
| 12 |
> |
// to any other in this class. |
| 13 |
> |
public UDPReader(int port, Logger logger){ |
| 14 |
> |
this.logger = logger; |
| 15 |
> |
this.port = port; |
| 16 |
> |
} |
| 17 |
> |
|
| 18 |
> |
public UDPReader(Logger logger){ |
| 19 |
> |
this(4589, logger); |
| 20 |
> |
} |
| 21 |
|
|
| 22 |
< |
// default UDP listening port. |
| 14 |
< |
int port = 4589; |
| 15 |
< |
final int packetSizeLimit = 8192; |
| 22 |
> |
public void run() { |
| 23 |
|
|
| 24 |
< |
// Allow the user to choose their own port number. |
| 25 |
< |
if (args.length == 1){ |
| 26 |
< |
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 |
< |
} |
| 24 |
> |
DatagramSocket socket = null; |
| 25 |
> |
try { |
| 26 |
> |
socket = new DatagramSocket(port); |
| 27 |
|
} |
| 28 |
+ |
catch (BindException e){ |
| 29 |
+ |
logger.write(this.toString(), Logger.SYSMSG, "Could not start the UDPReader thread on port "+port+" as this port was already in use."); |
| 30 |
+ |
return; |
| 31 |
+ |
} |
| 32 |
+ |
catch (Exception e){ |
| 33 |
+ |
logger.write(this.toString(), Logger.SYSMSG, "Could not start the UDPReader thread on port "+port+"."); |
| 34 |
+ |
return; |
| 35 |
+ |
} |
| 36 |
+ |
|
| 37 |
+ |
logger.write(this.toString(), Logger.SYSMSG, "UDPReader thread ready and listening for UDP packets on port "+port); |
| 38 |
|
|
| 39 |
< |
DatagramSocket socket = new DatagramSocket(port); |
| 40 |
< |
System.out.println("UDPReader ready and listening for UDP packets on port "+port); |
| 30 |
< |
|
| 39 |
> |
byte[] buf; |
| 40 |
> |
|
| 41 |
|
boolean running = true; |
| 42 |
|
while (running){ |
| 43 |
|
try { |
| 44 |
< |
byte[] buf = new byte[packetSizeLimit]; |
| 44 |
> |
buf = new byte[packetSizeLimit]; |
| 45 |
|
// receive request |
| 46 |
|
DatagramPacket packet = new DatagramPacket(buf, buf.length); |
| 47 |
|
socket.receive(packet); |
| 48 |
< |
UDPReaderThread thread = new UDPReaderThread(packet); |
| 49 |
< |
thread.run(); |
| 48 |
> |
UDPReaderThread t = new UDPReaderThread(); |
| 49 |
> |
t.run(packet); |
| 50 |
|
} |
| 51 |
|
catch (IOException e) { |
| 52 |
< |
System.out.println("An exception occured in the UDPReader!"); |
| 53 |
< |
e.printStackTrace(); |
| 52 |
> |
logger.write(this.toString(), Logger.SYSMSG, "The UDPReader thread has been shut down as an exception occured: "+e); |
| 53 |
> |
return; |
| 54 |
|
} |
| 55 |
|
} |
| 56 |
|
socket.close(); |
| 57 |
|
} |
| 58 |
+ |
|
| 59 |
+ |
|
| 60 |
+ |
Logger logger; |
| 61 |
+ |
int port; |
| 62 |
+ |
|
| 63 |
+ |
final int packetSizeLimit = 8192; |
| 64 |
+ |
|
| 65 |
|
} |
