server/filtermanager/HostListener.java

//---PACKAGE DECLARATION---
package uk.ac.ukc.iscream.filtermanager;

//---IMPORTS---
import uk.ac.ukc.iscream.core.*;
import uk.ac.ukc.iscream.filter.*;
import uk.ac.ukc.iscream.util.*;
import java.net.*;
import java.io.*;

/**
 * A socket listener to listen for new hosts registering with the system.
 * When a host makes a connection, the connecton is past to an instance
 * of the HostInit class, which handles further communication.
 *
 * @author  $Author: tdb1 $
 * @version $Id: HostListener.java,v 1.2 2000/11/29 19:19:12 tdb1 Exp $
 */
class HostListener extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.2 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

        /**
     * Constructs a new listener
     *
         * @param listenPort The port that the server will listen on.
         */
    public HostListener(int listenPort) {
        _listenPort = listenPort;
        _logger.write(toString(), Logger.SYSINIT, "started");
    }

    

//---PUBLIC METHODS---

        /**
         * The run() method is the main loop for this thread, and we
         * will remain in here until such a point as something goes
         * wrong with the listening. After initially setting up the
         * ServerSocket we go round a while loop receiving connections
         * and then passing them off to other processes to deal with.
         */
    public void run(){
        ServerSocket listenSocket=null;
                // We use this boolean so we can break out of the while loop if we want
        boolean run = true;
        try{
                        // Setup the ServerSocket so that clients can connect
            listenSocket = new ServerSocket(_listenPort);
        }
        catch(IOException e){
        }
                // Log what machine/port we're listening on
                try{
                        _logger.write(toString(), Logger.SYSMSG, "Server listening on "
                                                                                +InetAddress.getLocalHost().getHostName()
                                                                                +"/"+InetAddress.getLocalHost().getHostAddress()
                                                                                +" port "+listenSocket.getLocalPort());
                }
                catch(UnknownHostException e){
                        _logger.write(toString(), Logger.SYSMSG, "Server listening on UnknownHost "
                                                                                +"port "+listenSocket.getLocalPort());
                }
                // Loop round constantly until we decide to stop
        while(run){
            Socket hostSocket=null;
            try{
                _logger.write(toString(), Logger.SYSMSG, "Waiting for Connection");
                                // This will block until a host connects - at which point we get a Socket
                hostSocket = listenSocket.accept();
                _logger.write(toString(), Logger.SYSMSG, "Connection accepted from: " + hostSocket.toString());
            }
            catch(IOException e){
                                // Something went wrong with the ServerSocket, so we'll stop listening
                run=false;
            }
                        // If we've stopped on the line above we won't want to try this !
            if(run){
                                try {
                                    // Setup the HostInit so it can carry on communications with the host
                    HostInit init = new HostInit(hostSocket);
                                    // and start it
                    init.start();
                } catch (IOException e) {
                    _logger.write(toString(), Logger.ERROR, e.toString());
                }
            }
        }
                // Best log the fact that we're stopping
        _logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
    }

    /**
     * Overrides the {@link java.lang.Object#toString() Object.toString()}
     * method to provide clean logging (every class should have this).
     *
     * @return the name of this class and its CVS revision
     */
    public String toString() {
        return this.getClass().getName() + "(" + REVISION.substring(11, REVISION.length() - 2) + ")";
    }

//---PRIVATE METHODS---

//---ACCESSOR/MUTATOR METHODS---

//---ATTRIBUTES---
    
    /**
     * A reference to the logger the system is using
     */
    Logger _logger = ReferenceManager.getInstance().getLogger();
    
    /**
         * The port on which the server should listen.
         */
    private int _listenPort;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.3
Committed:	Thu Dec 7 00:02:17 2000 UTC (23 years, 5 months ago) by tdb
Branch:	MAIN
Branch point for:	SERVER_PACKAGEBUILD
Changes since 1.2:	+16 -33 lines
Log Message:	Had a tidy up. The Filter Manager now makes use of the Reference Manager, which ensures that we don't have lots of messy reference passing.
#	User	Rev	Content
1	tdb	1.1	//---PACKAGE DECLARATION---
2	tdb	1.2	package uk.ac.ukc.iscream.filtermanager;
3	tdb	1.1
4			//---IMPORTS---
5			import uk.ac.ukc.iscream.core.*;
6			import uk.ac.ukc.iscream.filter.*;
7	tdb	1.3	import uk.ac.ukc.iscream.util.*;
8			import java.net.*;
9			import java.io.*;
10	tdb	1.1
11			/**
12			* A socket listener to listen for new hosts registering with the system.
13			* When a host makes a connection, the connecton is past to an instance
14			* of the HostInit class, which handles further communication.
15			*
16			* @author $Author: tdb1 $
17	tdb	1.3	* @version $Id: HostListener.java,v 1.2 2000/11/29 19:19:12 tdb1 Exp $
18	tdb	1.1	*/
19			class HostListener extends Thread {
20
21			//---FINAL ATTRIBUTES---
22
23			/**
24			* The current CVS revision of this class
25			*/
26	tdb	1.3	public final String REVISION = "$Revision: 1.2 $";
27	tdb	1.1
28			//---STATIC METHODS---
29
30			//---CONSTRUCTORS---
31
32			/**
33			* Constructs a new listener
34			*
35	tdb	1.3	* @param listenPort The port that the server will listen on.
36	tdb	1.1	*/
37	tdb	1.3	public HostListener(int listenPort) {
38			_listenPort = listenPort;
39	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "started");
40			}
41
42
43
44			//---PUBLIC METHODS---
45
46			/**
47			* The run() method is the main loop for this thread, and we
48			* will remain in here until such a point as something goes
49			* wrong with the listening. After initially setting up the
50			* ServerSocket we go round a while loop receiving connections
51			* and then passing them off to other processes to deal with.
52			*/
53			public void run(){
54	tdb	1.3	ServerSocket listenSocket=null;
55	tdb	1.1	// We use this boolean so we can break out of the while loop if we want
56			boolean run = true;
57			try{
58			// Setup the ServerSocket so that clients can connect
59	tdb	1.3	listenSocket = new ServerSocket(_listenPort);
60	tdb	1.1	}
61			catch(IOException e){
62			}
63			// Log what machine/port we're listening on
64			try{
65			_logger.write(toString(), Logger.SYSMSG, "Server listening on "
66			+InetAddress.getLocalHost().getHostName()
67			+"/"+InetAddress.getLocalHost().getHostAddress()
68	tdb	1.3	+" port "+listenSocket.getLocalPort());
69	tdb	1.1	}
70			catch(UnknownHostException e){
71			_logger.write(toString(), Logger.SYSMSG, "Server listening on UnknownHost "
72	tdb	1.3	+"port "+listenSocket.getLocalPort());
73	tdb	1.1	}
74			// Loop round constantly until we decide to stop
75			while(run){
76			Socket hostSocket=null;
77			try{
78			_logger.write(toString(), Logger.SYSMSG, "Waiting for Connection");
79			// This will block until a host connects - at which point we get a Socket
80	tdb	1.3	hostSocket = listenSocket.accept();
81	tdb	1.1	_logger.write(toString(), Logger.SYSMSG, "Connection accepted from: " + hostSocket.toString());
82			}
83			catch(IOException e){
84			// Something went wrong with the ServerSocket, so we'll stop listening
85			run=false;
86			}
87			// If we've stopped on the line above we won't want to try this !
88			if(run){
89			try {
90			// Setup the HostInit so it can carry on communications with the host
91	tdb	1.3	HostInit init = new HostInit(hostSocket);
92	tdb	1.1	// and start it
93			init.start();
94			} catch (IOException e) {
95			_logger.write(toString(), Logger.ERROR, e.toString());
96			}
97			}
98			}
99			// Best log the fact that we're stopping
100			_logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
101			}
102
103			/**
104			* Overrides the {@link java.lang.Object#toString() Object.toString()}
105			* method to provide clean logging (every class should have this).
106			*
107			* @return the name of this class and its CVS revision
108			*/
109			public String toString() {
110			return this.getClass().getName() + "(" + REVISION.substring(11, REVISION.length() - 2) + ")";
111			}
112
113			//---PRIVATE METHODS---
114
115			//---ACCESSOR/MUTATOR METHODS---
116
117			//---ATTRIBUTES---
118
119			/**
120			* A reference to the logger the system is using
121			*/
122	tdb	1.3	Logger _logger = ReferenceManager.getInstance().getLogger();
123	tdb	1.1
124			/**
125			* The port on which the server should listen.
126			*/
127	tdb	1.3	private int _listenPort;
128	tdb	1.1
129			//---STATIC ATTRIBUTES---
130
131			}