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import java.io.*; |
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import java.net.*; |
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import java.util.*; |
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import uk.ac.ukc.iscream.core.*; |
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import uk.ac.ukc.iscream.filter.*; |
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|
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// This class contains the main method to be run by |
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// the filter children. It harvests UDP traffic. |
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// |
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// |
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public class UDPReader extends Thread{ |
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|
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// It is normal to use this constructor in preference |
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// to any other in this class. |
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public UDPReader(int port, Filter parent, Logger logger){ |
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this.logger = logger; |
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this.port = port; |
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this.parent = parent; |
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} |
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|
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public UDPReader(Filter parent, Logger logger){ |
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this(4589, parent, logger); |
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} |
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|
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public void run() { |
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|
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DatagramSocket socket = null; |
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try { |
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socket = new DatagramSocket(port); |
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} |
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catch (BindException e){ |
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logger.write(this.toString(), Logger.SYSMSG, "Could not start the UDPReader thread on port "+port+" as this port was already in use."); |
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return; |
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} |
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catch (Exception e){ |
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logger.write(this.toString(), Logger.SYSMSG, "Could not start the UDPReader thread on port "+port+"."); |
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return; |
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} |
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|
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logger.write(this.toString(), Logger.SYSMSG, "UDPReader thread ready and listening for UDP packets on port "+port); |
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|
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byte[] buf; |
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|
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boolean running = true; |
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while (running){ |
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try { |
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buf = new byte[packetSizeLimit]; |
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// receive request |
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DatagramPacket packet = new DatagramPacket(buf, buf.length); |
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socket.receive(packet); |
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FilterThread t = new FilterThread(parent); |
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t.run(packet); |
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} |
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catch (IOException e) { |
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logger.write(this.toString(), Logger.SYSMSG, "The UDPReader thread has been shut down as an exception occured: "+e); |
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return; |
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} |
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} |
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socket.close(); |
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} |
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|
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|
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Logger logger; |
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int port; |
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Filter parent; |
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|
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final int packetSizeLimit = 8192; |
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|
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} |
