server/clientinterface/TCPControlHandler.java

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

//---IMPORTS---
import uk.ac.ukc.iscream.util.*;
import uk.ac.ukc.iscream.componentmanager.*;
import uk.ac.ukc.iscream.core.*;
import java.net.Socket;
import java.net.ServerSocket;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.PrintWriter;
import java.io.InputStreamReader;


/**
 * Acts as a Control Handler to a TCP based client.
 *
 * @author  $Author: tdb1 $
 * @version $Id: TCPControlHandler.java,v 1.7 2001/01/24 00:43:19 tdb1 Exp $
 */
class TCPControlHandler extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.7 $";
    
    public static final String PROTOVER = "PROTOCOL 1.1";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    public TCPControlHandler(Socket socket, PacketSorter ps) throws IOException {
        _socket = socket;
        _ps = ps;
        _socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
        _socketOut = new PrintWriter(_socket.getOutputStream());
        _hostList = "";
        _logger.write(toString(), Logger.SYSINIT, "created");
    }
    
//---PUBLIC METHODS---

    public void run() {
        boolean run = true;
        // lets init some communications with the client
        try {
            _socketOut.println(PROTOVER);
            _socketOut.flush();
            _clientName = _socketIn.readLine();
            _socketOut.println("OK");
            _socketOut.flush();
        }
        catch(IOException e) {
            _logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
            run=false;
        }
        
        _logger.write(toString(), Logger.SYSMSG, "Client has connected: "+_clientName);
        
        while(run) {
            try {
                String cmd = _socketIn.readLine();
                if(cmd.equals("STARTCONFIG")) {
                    Configuration myConfig = _configManager.getConfiguration("Client."+_clientName);
                    _socketOut.println("OK");
                    _socketOut.flush();
                    // get properties
                    cmd = _socketIn.readLine();
                    while(!cmd.equals("ENDCONFIG")) {
                        // get the property
                        if(cmd.startsWith("Client.") || cmd.startsWith("Host.")) {
                            try {
                                String returnedProperty = myConfig.getProperty(cmd);    
                                _socketOut.println(returnedProperty);
                                _socketOut.flush();
                            }
                            catch (org.omg.CORBA.MARSHAL e) {
                                _socketOut.println("ERROR");
                                _socketOut.flush();
                            }
                        }
                        else {
                            _socketOut.println("ERROR");
                            _socketOut.flush();
                        }
                        cmd = _socketIn.readLine();
                    }
                    _socketOut.println("OK");
                    _socketOut.flush();
                    _logger.write(toString(), Logger.SYSMSG, "Client has been configured");
                    
                }
                else if(cmd.equals("STARTDATA")) {
                    if(_dataHandler == null) {
                        // create a serversocket
                        ServerSocket ss = new ServerSocket(0);
                        // get the port
                        int port = ss.getLocalPort();
                        // tell the client
                        _socketOut.println(port);
                        _socketOut.flush();
                        // call accept()
                        Socket s = ss.accept();
                        // when we get the Socket back, give it to the data thread
                        TCPDataHandler dh = new TCPDataHandler(s);
                        // register it !
                        _ps.register(dh.getQueue(), _hostList);
                        // start it up
                        dh.start();
                        // HOLD a ref to that data thread
                        _dataHandler = dh;
                        _socketOut.println("OK");
                        _socketOut.flush();
                        _logger.write(toString(), Logger.SYSMSG, "Data stream started at Clients Request on port: "+port);
                    }
                    else {
                        _socketOut.println("ERROR");
                        _socketOut.flush();
                    }
                }
                else if(cmd.equals("STOPDATA")) {
                    if(_dataHandler != null) {
                        // Deregister
                        _ps.deregister(_dataHandler.getQueue(), _hostList);
                        // Shut down the data handler
                        _dataHandler.shutdown();
                        // destroy the reference to it ?
                        _dataHandler = null;
                        _socketOut.println("OK");
                        _socketOut.flush();
                        _logger.write(toString(), Logger.SYSMSG, "Data stream stopped at Clients Request");
                    }
                    else {
                        _socketOut.println("ERROR");
                        _socketOut.flush();
                    }
                }
                else if(cmd.equals("SETHOSTLIST")) {
                    if(_dataHandler == null) {
                        _socketOut.println("OK");
                        _socketOut.flush();
                        cmd = _socketIn.readLine();
                        _hostList = cmd;
                        _socketOut.println("OK");
                        _socketOut.flush();
                    }
                    else {
                        _socketOut.println("ERROR");
                        _socketOut.flush();
                    }
                }
                else if(cmd.equals("DISCONNECT")) {
                    run=false;
                    if(_dataHandler != null) {
                        // Deregister
                        _ps.deregister(_dataHandler.getQueue(), _hostList);
                        // Shut down the data handler
                        _dataHandler.shutdown();
                        // destroy the reference to it ?
                        _dataHandler = null;
                        _socketOut.println("OK");
                        _socketOut.flush();
                        _logger.write(toString(), Logger.SYSMSG, "Data stream stopped at Clients Request");
                    }
                    _socketOut.println("OK");
                    _socketOut.flush();
                    _socketIn.close();
                    _socketOut.close();
                    _socket.close();
                    _logger.write(toString(), Logger.SYSMSG, "Closing at Clients Request");
                }
                else {
                    _socketOut.println("ERROR");
                    _socketOut.flush();
                }
            }
            catch(IOException e) {
                run=false;
                _logger.write(toString(), Logger.FATAL, "Fatal communication error, shutdown pending");
            }
        }
        _logger.write(toString(), Logger.SYSMSG, "Shutting down Control Handler, client has gone.");
    }
  
    /**
     * 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();
    
    /**
     * A reference to the Configuration Manager the system is using
     */
    private ConfigurationManager _configManager = ReferenceManager.getInstance().getCM();
    

    /**
     * The socket we are talking on
     */
    private Socket _socket;

    /**
     * A hook to the inbound data from the socket
     */
    private BufferedReader _socketIn;

    /**
     * A hook to the outbound stream for the socket
     */
    private PrintWriter _socketOut;
    
    /**
         * A reference to the PacketSorter.
         */
    private PacketSorter _ps;
    
    private TCPDataHandler _dataHandler;
    
    private String _clientName;
    private String _hostList;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.8
Committed:	Wed Jan 24 00:55:33 2001 UTC (23 years, 4 months ago) by tdb
Branch:	MAIN
Changes since 1.7:	+9 -3 lines
Log Message:	A bit of tightening up. I think this will have caught the NullPointer exception that was been thrown when clients "uncleanly" disconnected.
#	User	Rev	Content
1	tdb	1.1	//---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.componentmanager.*;
7			import uk.ac.ukc.iscream.core.*;
8			import java.net.Socket;
9			import java.net.ServerSocket;
10			import java.io.InputStream;
11			import java.io.OutputStream;
12			import java.io.IOException;
13			import java.io.BufferedReader;
14			import java.io.PrintWriter;
15			import java.io.InputStreamReader;
16
17
18			/**
19			* Acts as a Control Handler to a TCP based client.
20			*
21	tdb	1.2	* @author $Author: tdb1 $
22	tdb	1.8	* @version $Id: TCPControlHandler.java,v 1.7 2001/01/24 00:43:19 tdb1 Exp $
23	tdb	1.1	*/
24			class TCPControlHandler extends Thread {
25
26			//---FINAL ATTRIBUTES---
27
28			/**
29			* The current CVS revision of this class
30			*/
31	tdb	1.8	public final String REVISION = "$Revision: 1.7 $";
32	tdb	1.1
33	tdb	1.4	public static final String PROTOVER = "PROTOCOL 1.1";
34	tdb	1.1
35			//---STATIC METHODS---
36
37			//---CONSTRUCTORS---
38
39	tdb	1.4	public TCPControlHandler(Socket socket, PacketSorter ps) throws IOException {
40	tdb	1.1	_socket = socket;
41	tdb	1.4	_ps = ps;
42	tdb	1.1	_socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
43			_socketOut = new PrintWriter(_socket.getOutputStream());
44	tdb	1.4	_hostList = "";
45	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "created");
46			}
47
48			//---PUBLIC METHODS---
49
50			public void run() {
51			boolean run = true;
52			// lets init some communications with the client
53			try {
54			_socketOut.println(PROTOVER);
55			_socketOut.flush();
56			_clientName = _socketIn.readLine();
57			_socketOut.println("OK");
58			_socketOut.flush();
59			}
60			catch(IOException e) {
61			_logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
62			run=false;
63			}
64
65			_logger.write(toString(), Logger.SYSMSG, "Client has connected: "+_clientName);
66
67			while(run) {
68			try {
69			String cmd = _socketIn.readLine();
70			if(cmd.equals("STARTCONFIG")) {
71			Configuration myConfig = _configManager.getConfiguration("Client."+_clientName);
72			_socketOut.println("OK");
73			_socketOut.flush();
74			// get properties
75			cmd = _socketIn.readLine();
76			while(!cmd.equals("ENDCONFIG")) {
77			// get the property
78	tdb	1.7	if(cmd.startsWith("Client.") \|\| cmd.startsWith("Host.")) {
79			try {
80			String returnedProperty = myConfig.getProperty(cmd);
81			_socketOut.println(returnedProperty);
82			_socketOut.flush();
83			}
84			catch (org.omg.CORBA.MARSHAL e) {
85			_socketOut.println("ERROR");
86			_socketOut.flush();
87			}
88			}
89			else {
90	tdb	1.1	_socketOut.println("ERROR");
91			_socketOut.flush();
92			}
93			cmd = _socketIn.readLine();
94			}
95			_socketOut.println("OK");
96			_socketOut.flush();
97			_logger.write(toString(), Logger.SYSMSG, "Client has been configured");
98
99			}
100			else if(cmd.equals("STARTDATA")) {
101			if(_dataHandler == null) {
102			// create a serversocket
103			ServerSocket ss = new ServerSocket(0);
104			// get the port
105			int port = ss.getLocalPort();
106			// tell the client
107			_socketOut.println(port);
108			_socketOut.flush();
109			// call accept()
110			Socket s = ss.accept();
111			// when we get the Socket back, give it to the data thread
112	tdb	1.4	TCPDataHandler dh = new TCPDataHandler(s);
113			// register it !
114			_ps.register(dh.getQueue(), _hostList);
115	tdb	1.2	// start it up
116			dh.start();
117	tdb	1.1	// HOLD a ref to that data thread
118			_dataHandler = dh;
119			_socketOut.println("OK");
120			_socketOut.flush();
121			_logger.write(toString(), Logger.SYSMSG, "Data stream started at Clients Request on port: "+port);
122			}
123			else {
124			_socketOut.println("ERROR");
125			_socketOut.flush();
126			}
127			}
128			else if(cmd.equals("STOPDATA")) {
129			if(_dataHandler != null) {
130	tdb	1.6	// Deregister
131			_ps.deregister(_dataHandler.getQueue(), _hostList);
132	tdb	1.2	// Shut down the data handler
133	tdb	1.1	_dataHandler.shutdown();
134			// destroy the reference to it ?
135			_dataHandler = null;
136			_socketOut.println("OK");
137			_socketOut.flush();
138			_logger.write(toString(), Logger.SYSMSG, "Data stream stopped at Clients Request");
139			}
140			else {
141			_socketOut.println("ERROR");
142			_socketOut.flush();
143			}
144			}
145	tdb	1.4	else if(cmd.equals("SETHOSTLIST")) {
146	tdb	1.5	if(_dataHandler == null) {
147			_socketOut.println("OK");
148			_socketOut.flush();
149			cmd = _socketIn.readLine();
150			_hostList = cmd;
151			_socketOut.println("OK");
152			_socketOut.flush();
153			}
154			else {
155			_socketOut.println("ERROR");
156			_socketOut.flush();
157			}
158	tdb	1.4	}
159	tdb	1.2	else if(cmd.equals("DISCONNECT")) {
160	tdb	1.1	run=false;
161	tdb	1.3	if(_dataHandler != null) {
162	tdb	1.8	// Deregister
163			_ps.deregister(_dataHandler.getQueue(), _hostList);
164	tdb	1.3	// Shut down the data handler
165			_dataHandler.shutdown();
166			// destroy the reference to it ?
167			_dataHandler = null;
168	tdb	1.8	_socketOut.println("OK");
169			_socketOut.flush();
170	tdb	1.3	_logger.write(toString(), Logger.SYSMSG, "Data stream stopped at Clients Request");
171			}
172	tdb	1.1	_socketOut.println("OK");
173			_socketOut.flush();
174			_socketIn.close();
175			_socketOut.close();
176			_socket.close();
177			_logger.write(toString(), Logger.SYSMSG, "Closing at Clients Request");
178			}
179			else {
180			_socketOut.println("ERROR");
181			_socketOut.flush();
182			}
183			}
184			catch(IOException e) {
185	tdb	1.8	run=false;
186			_logger.write(toString(), Logger.FATAL, "Fatal communication error, shutdown pending");
187	tdb	1.1	}
188			}
189	tdb	1.8	_logger.write(toString(), Logger.SYSMSG, "Shutting down Control Handler, client has gone.");
190	tdb	1.1	}
191
192			/**
193			* Overrides the {@link java.lang.Object#toString() Object.toString()}
194			* method to provide clean logging (every class should have this).
195			*
196			* This uses the uk.ac.ukc.iscream.util.NameFormat class
197			* to format the toString()
198			*
199			* @return the name of this class and its CVS revision
200			*/
201			public String toString() {
202			return FormatName.getName(
203			_name,
204			getClass().getName(),
205			REVISION);
206			}
207
208			//---PRIVATE METHODS---
209
210			//---ACCESSOR/MUTATOR METHODS---
211
212			//---ATTRIBUTES---
213
214			/**
215			* This is the friendly identifier of the
216			* component this class is running in.
217			* eg, a Filter may be called "filter1",
218			* If this class does not have an owning
219			* component, a name from the configuration
220			* can be placed here. This name could also
221			* be changed to null for utility classes.
222			*/
223			private String _name = ClientInterfaceMain.NAME;
224
225			/**
226			* This holds a reference to the
227			* system logger that is being used.
228			*/
229			private Logger _logger = ReferenceManager.getInstance().getLogger();
230
231			/**
232			* A reference to the Configuration Manager the system is using
233			*/
234			private ConfigurationManager _configManager = ReferenceManager.getInstance().getCM();
235
236
237			/**
238			* The socket we are talking on
239			*/
240			private Socket _socket;
241
242			/**
243			* A hook to the inbound data from the socket
244			*/
245			private BufferedReader _socketIn;
246
247			/**
248			* A hook to the outbound stream for the socket
249			*/
250			private PrintWriter _socketOut;
251	tdb	1.4
252	tdb	1.1	/**
253	tdb	1.4	* A reference to the PacketSorter.
254			*/
255			private PacketSorter _ps;
256	tdb	1.1
257			private TCPDataHandler _dataHandler;
258
259			private String _clientName;
260	tdb	1.4	private String _hostList;
261	tdb	1.1
262			//---STATIC ATTRIBUTES---
263
264			}