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//---PACKAGE DECLARATION--- |
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package uk.ac.ukc.iscream.filtermanager; |
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|
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//---IMPORTS--- |
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import uk.ac.ukc.iscream.core.*; |
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import uk.ac.ukc.iscream.componentmanager.*; |
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import uk.ac.ukc.iscream.filter.*; |
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import uk.ac.ukc.iscream.util.*; |
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import java.net.*; |
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import java.io.*; |
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|
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/** |
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* A socket listener to listen for new hosts registering with the system. |
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* When a host makes a connection, the connecton is past to an instance |
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* of the HostInit class, which handles further communication. |
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* |
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* @author $Author: tdb1 $ |
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* @version $Id: HostListener.java,v 1.5 2001/01/18 23:17:54 tdb1 Exp $ |
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*/ |
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class HostListener extends Thread { |
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|
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//---FINAL ATTRIBUTES--- |
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|
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/** |
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* The current CVS revision of this class |
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*/ |
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public final String REVISION = "$Revision: 1.5 $"; |
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|
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//---STATIC METHODS--- |
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|
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//---CONSTRUCTORS--- |
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|
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/** |
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* Constructs a new listener |
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* |
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* @param listenPort The port that the server will listen on. |
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*/ |
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public HostListener(int listenPort) { |
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// set the Thread name |
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setName("filtermanager.HostListener"); |
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|
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_listenPort = listenPort; |
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_logger.write(toString(), Logger.SYSINIT, "started"); |
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} |
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|
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|
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|
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//---PUBLIC METHODS--- |
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|
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/** |
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* The run() method is the main loop for this thread, and we |
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* will remain in here until such a point as something goes |
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* wrong with the listening. After initially setting up the |
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* ServerSocket we go round a while loop receiving connections |
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* and then passing them off to other processes to deal with. |
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*/ |
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public void run(){ |
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ServerSocket listenSocket=null; |
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// We use this boolean so we can break out of the while loop if we want |
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boolean run = true; |
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try{ |
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// Setup the ServerSocket so that clients can connect |
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listenSocket = new ServerSocket(_listenPort); |
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} |
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catch(IOException e){ |
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} |
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// Log what machine/port we're listening on |
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try{ |
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_logger.write(toString(), Logger.SYSMSG, "Server listening on " |
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+InetAddress.getLocalHost().getHostName() |
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+"/"+InetAddress.getLocalHost().getHostAddress() |
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+" port "+listenSocket.getLocalPort()); |
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} |
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catch(UnknownHostException e){ |
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_logger.write(toString(), Logger.SYSMSG, "Server listening on UnknownHost " |
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+"port "+listenSocket.getLocalPort()); |
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} |
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// Loop round constantly until we decide to stop |
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while(run){ |
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Socket hostSocket=null; |
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try{ |
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_logger.write(toString(), Logger.SYSMSG, "Waiting for Connection"); |
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// This will block until a host connects - at which point we get a Socket |
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hostSocket = listenSocket.accept(); |
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_logger.write(toString(), Logger.SYSMSG, "Connection accepted from: " + hostSocket.toString()); |
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} |
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catch(IOException e){ |
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// Something went wrong with the ServerSocket, so we'll stop listening |
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run=false; |
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} |
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// If we've stopped on the line above we won't want to try this ! |
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if(run){ |
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try { |
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// Setup the HostInit so it can carry on communications with the host |
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HostInit init = new HostInit(hostSocket); |
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// and start it |
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init.start(); |
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} catch (IOException e) { |
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_logger.write(toString(), Logger.ERROR, e.toString()); |
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} |
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} |
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} |
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// Best log the fact that we're stopping |
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_logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending"); |
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} |
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|
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/** |
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* Overrides the {@link java.lang.Object#toString() Object.toString()} |
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* method to provide clean logging (every class should have this). |
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* |
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* This uses the uk.ac.ukc.iscream.util.NameFormat class |
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* to format the toString() |
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* |
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* @return the name of this class and its CVS revision |
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*/ |
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public String toString() { |
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return FormatName.getName( |
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_name, |
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this.getClass().getName(), |
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REVISION); |
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} |
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|
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//---PRIVATE METHODS--- |
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|
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//---ACCESSOR/MUTATOR METHODS--- |
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|
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//---ATTRIBUTES--- |
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|
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/** |
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* This holds a reference to the |
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* system logger that is being used. |
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*/ |
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private Logger _logger = ReferenceManager.getInstance().getLogger(); |
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|
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/** |
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* This is the friendly identifier of the |
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* component this class is running in. |
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* eg, a Filter may be called "filter1", |
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* If this class does not have an owning |
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* component, a name from the configuration |
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* can be placed here. This name could also |
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* be changed to null for utility classes. |
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*/ |
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private String _name = FilterManager.NAME; |
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|
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/** |
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* The port on which the server should listen. |
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*/ |
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private int _listenPort; |
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|
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//---STATIC ATTRIBUTES--- |
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|
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} |
