server/clientinterface/TCPClientListener.java

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

//---IMPORTS---
import uk.ac.ukc.iscream.util.*;
import uk.ac.ukc.iscream.core.*;
import uk.ac.ukc.iscream.componentmanager.*;
import java.io.IOException;
import java.net.Socket;
import java.net.ServerSocket;
import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * Listener for incoming clients.
 * Creates a local implementation of the ClientHandler interface
 * and registers this with the ClientInterfaceServant. It then
 * returns a "reference" to this ClientHandler back to the client.
 *
 * @author  $Author: ajm4 $
 * @version $Id: ClientListener.java,v 1.2 2000/12/13 12:57:38 ajm4 Exp $
 */
class ClientListener extends Thread {

//---FINAL ATTRIBUTES---

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

//---CONSTRUCTORS---

        /**
     * Constructs a new ClientListener
     *
         * @param port The port that the server will listen on.
         * @param clit A reference to the ClientInterfaceServant.
         */
    public ClientListener(int port, ClientInterfaceServant cli) {
        _port = port;
        _cli = cli;
        _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 listenPort=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
            listenPort = new ServerSocket(_port);
        }
        catch(IOException e){
        }
                // Log what machine/port we're listening on
                try{
                        _logger.write(toString(), Logger.SYSMSG, "ClientListener listening on "
                                                                                +InetAddress.getLocalHost().getHostName()
                                                                                +"/"+InetAddress.getLocalHost().getHostAddress()
                                                                                +" port "+listenPort.getLocalPort());
                }
                catch(UnknownHostException e){
                        _logger.write(toString(), Logger.SYSMSG, "ClientListener listening on UnknownHost "
                                                                                +"port "+listenPort.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 = listenPort.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
                                    ClientHandler handler = new TCPClientHandler(hostSocket, _cli);
                                    // register it
                                    _cli.register(handler);
                                    // then we can leave here.... I trust handler won't go out of scope !
                } 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).
     *
     * This uses the uk.ac.ukc.iscream.util.NameFormat class
     * to format the toString()
     *
     * @return the name of this class and its CVS revision
     */
    public String toString() {
        return FormatName.getName(
            _name,
            getClass().getName(),
            REVISION);
    }

//---PRIVATE METHODS---

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

//---ATTRIBUTES---

    /**
     * This is the friendly identifier of the
     * component this class is running in.
     * eg, a Filter may be called "filter1",
     * If this class does not have an owning
     * component,  a name from the configuration
     * can be placed here.  This name could also
     * be changed to null for utility classes.
     */
    private String _name = ClientInterfaceMain.NAME;

    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    private Logger _logger = ReferenceManager.getInstance().getLogger();

    /**
         * The port on which the server should listen.
         */
    private int _port;
    
    /**
         * A reference to the ClientInterfaceServant.
         */
    private ClientInterfaceServant _cli;

//---STATIC ATTRIBUTES---

}
Revision:	1.3
Committed:	Thu Jan 18 23:08:42 2001 UTC (23 years, 4 months ago) by tdb
Branch:	MAIN
Changes since 1.2:	+4 -3 lines
Log Message:	Changes to reflect move of Component, ComponentStartException, and the ReferenceManager from util to componentmanager.
#	User	Rev	Content
1	ajm	1.2	//---PACKAGE DECLARATION---
2			package uk.ac.ukc.iscream.clientinterface;
3
4			//---IMPORTS---
5			import uk.ac.ukc.iscream.util.*;
6			import uk.ac.ukc.iscream.core.*;
7	tdb	1.3	import uk.ac.ukc.iscream.componentmanager.*;
8	ajm	1.2	import java.io.IOException;
9			import java.net.Socket;
10			import java.net.ServerSocket;
11			import java.net.InetAddress;
12			import java.net.UnknownHostException;
13
14			/**
15			* Listener for incoming clients.
16			* Creates a local implementation of the ClientHandler interface
17			* and registers this with the ClientInterfaceServant. It then
18			* returns a "reference" to this ClientHandler back to the client.
19			*
20	tdb	1.3	* @author $Author: ajm4 $
21			* @version $Id: ClientListener.java,v 1.2 2000/12/13 12:57:38 ajm4 Exp $
22	ajm	1.2	*/
23			class ClientListener extends Thread {
24
25			//---FINAL ATTRIBUTES---
26
27			/**
28			* The current CVS revision of this class
29			*/
30	tdb	1.3	public final String REVISION = "$Revision: 1.2 $";
31	ajm	1.2
32			//---STATIC METHODS---
33
34			//---CONSTRUCTORS---
35
36			/**
37			* Constructs a new ClientListener
38			*
39			* @param port The port that the server will listen on.
40			* @param clit A reference to the ClientInterfaceServant.
41			*/
42			public ClientListener(int port, ClientInterfaceServant cli) {
43			_port = port;
44			_cli = cli;
45			_logger.write(toString(), Logger.SYSINIT, "started");
46			}
47
48			//---PUBLIC METHODS---
49
50			/**
51			* The run() method is the main loop for this thread, and we
52			* will remain in here until such a point as something goes
53			* wrong with the listening. After initially setting up the
54			* ServerSocket we go round a while loop receiving connections
55			* and then passing them off to other processes to deal with.
56			*/
57			public void run(){
58			ServerSocket listenPort=null;
59			// We use this boolean so we can break out of the while loop if we want
60			boolean run = true;
61			try{
62			// Setup the ServerSocket so that clients can connect
63			listenPort = new ServerSocket(_port);
64			}
65			catch(IOException e){
66			}
67			// Log what machine/port we're listening on
68			try{
69			_logger.write(toString(), Logger.SYSMSG, "ClientListener listening on "
70			+InetAddress.getLocalHost().getHostName()
71			+"/"+InetAddress.getLocalHost().getHostAddress()
72			+" port "+listenPort.getLocalPort());
73			}
74			catch(UnknownHostException e){
75			_logger.write(toString(), Logger.SYSMSG, "ClientListener listening on UnknownHost "
76			+"port "+listenPort.getLocalPort());
77			}
78			// Loop round constantly until we decide to stop
79			while(run){
80			Socket hostSocket=null;
81			try{
82			_logger.write(toString(), Logger.SYSMSG, "Waiting for Connection");
83			// This will block until a host connects - at which point we get a Socket
84			hostSocket = listenPort.accept();
85			_logger.write(toString(), Logger.SYSMSG, "Connection accepted from: " + hostSocket.toString());
86			}
87			catch(IOException e){
88			// Something went wrong with the ServerSocket, so we'll stop listening
89			run=false;
90			}
91			// If we've stopped on the line above we won't want to try this !
92			if(run){
93			try {
94			// Setup the HostInit so it can carry on communications with the host
95			ClientHandler handler = new TCPClientHandler(hostSocket, _cli);
96			// register it
97			_cli.register(handler);
98			// then we can leave here.... I trust handler won't go out of scope !
99			} catch (IOException e) {
100			_logger.write(toString(), Logger.ERROR, e.toString());
101			}
102			}
103			}
104			// Best log the fact that we're stopping
105			_logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
106			}
107
108			/**
109			* Overrides the {@link java.lang.Object#toString() Object.toString()}
110			* method to provide clean logging (every class should have this).
111			*
112			* This uses the uk.ac.ukc.iscream.util.NameFormat class
113			* to format the toString()
114			*
115			* @return the name of this class and its CVS revision
116			*/
117			public String toString() {
118			return FormatName.getName(
119			_name,
120			getClass().getName(),
121			REVISION);
122			}
123
124			//---PRIVATE METHODS---
125
126			//---ACCESSOR/MUTATOR METHODS---
127
128			//---ATTRIBUTES---
129
130			/**
131			* This is the friendly identifier of the
132			* component this class is running in.
133			* eg, a Filter may be called "filter1",
134			* If this class does not have an owning
135			* component, a name from the configuration
136			* can be placed here. This name could also
137			* be changed to null for utility classes.
138			*/
139			private String _name = ClientInterfaceMain.NAME;
140
141			/**
142			* This holds a reference to the
143			* system logger that is being used.
144			*/
145			private Logger _logger = ReferenceManager.getInstance().getLogger();
146
147			/**
148			* The port on which the server should listen.
149			*/
150			private int _port;
151
152			/**
153			* A reference to the ClientInterfaceServant.
154			*/
155			private ClientInterfaceServant _cli;
156
157			//---STATIC ATTRIBUTES---
158
159			}