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 1.8 2001/01/24 00:55:33 tdb1 Exp $
 */
class TCPControlHandler extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.8 $";
    
    /**
     * This is our protocol version. It is hardcoded to ensure
     * that it doesn't get accidently changed. A change to the
     * protocol would also require changing this classes code !
     */
    public static final String PROTOVER = "PROTOCOL 1.1";
    
//---STATIC METHODS---

//---CONSTRUCTORS---
    
    /**
     * Construct a new TCPControlHandler, and setup the reader
     * and writer for the new Socket.
     *
     * @param socket The Socket connected to the new Client
     * @param packetSorter A reference to the PacketSorter in the component
     */
    public TCPControlHandler(Socket socket, PacketSorter packetSorter) throws IOException {
        _socket = socket;
        _packetSorter = packetSorter;
        // setup the reader & writer
        _socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
        _socketOut = new PrintWriter(_socket.getOutputStream());
        // set the default hostlist to "all host", for backward compatibility
        _hostList = "";
        _logger.write(toString(), Logger.SYSINIT, "created");
    }
    
//---PUBLIC METHODS---
    
    /**
     * This method initiates the thread, setting things up, and then
     * reading commands from the Client. It handles setting up of the
     * DataHandler, and clean shutting down.
     */
    public void run() {
        boolean run = true;
        // Tell the client our protocol, and ask it for it's name
        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);
        
        // loop until we decide to shutdown (run=false)
        while(run) {
            try {
                String cmd = _socketIn.readLine();
                // make a decision about what to do
                if(cmd.equals("STARTCONFIG")) {
                    // get the configuration for this client
                    Configuration myConfig = _configManager.getConfiguration("Client."+_clientName);
                    _socketOut.println("OK");
                    _socketOut.flush();
                    // get properties
                    cmd = _socketIn.readLine();
                    // provide all the requested properties
                    while(!cmd.equals("ENDCONFIG")) {
                        // client is restricted to this properties
                        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 we don't have a DataHandler, set one up
                    if(_dataHandler == null) {
                        // create a serversocket
                        ServerSocket ss = new ServerSocket(0);
                        // get the port
                        int port = ss.getLocalPort();
                        // tell the client the port
                        _socketOut.println(port);
                        _socketOut.flush();
                        // wait for the client to connect
                        Socket s = ss.accept();
                        // when we get the Socket back, give it to the data thread
                        TCPDataHandler dh = new TCPDataHandler(s);
                        // register the DataHandler's queue, giving the host list
                        _packetSorter.register(dh.getQueue(), _hostList);
                        // start up the DataHandler
                        dh.start();
                        // Hold a reference to the DataHandler, so we can stop it later
                        _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 we have a DataHandler, shut it down
                    if(_dataHandler != null) {
                        // Deregister the DataHandler, giving the host list
                        _packetSorter.deregister(_dataHandler.getQueue(), _hostList);
                        // Shut down the data handler
                        _dataHandler.shutdown();
                        // Destroy our reference, leaving it for the GC
                        _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")) {
                    // we can only set the host list when
                    // the DataHandler is not connected
                    if(_dataHandler == null) {
                        _socketOut.println("OK");
                        _socketOut.flush();
                        // read and set the host list
                        cmd = _socketIn.readLine();
                        _hostList = cmd;
                        _socketOut.println("OK");
                        _socketOut.flush();
                    }
                    else {
                        _socketOut.println("ERROR");
                        _socketOut.flush();
                    }
                }
                else if(cmd.equals("DISCONNECT")) {
                    // we going to disconnect, so lets stop this loop
                    run=false;
                    // if there is a DataHandler, we'd best shut it down
                    if(_dataHandler != null) {
                        // Deregister the DataHandler, giving the host list
                        _packetSorter.deregister(_dataHandler.getQueue(), _hostList);
                        // Shut down the data handler
                        _dataHandler.shutdown();
                        // Destroy our reference, leaving it for the GC
                        _dataHandler = null;
                        _socketOut.println("OK");
                        _socketOut.flush();
                        _logger.write(toString(), Logger.SYSMSG, "Data stream stopped at Clients Request");
                    }
                    _socketOut.println("OK");
                    _socketOut.flush();
                    // close the reader, writer and Socket
                    _socketIn.close();
                    _socketOut.close();
                    _socket.close();
                    _logger.write(toString(), Logger.SYSMSG, "Closing at Clients Request");
                }
                else {
                    _socketOut.println("ERROR");
                    _socketOut.flush();
                }
            }
            catch(IOException e) {
                // if we get an exception, the client has probably left, so we stop
                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 _packetSorter;
    
    /**
     * A reference to the DataHandler, if there is one
     */
    private TCPDataHandler _dataHandler;
    
    /**
     * The name of the Client we're connected to
     */
    private String _clientName;
    
    /**
     * The host list the Client has requested
     */
    private String _hostList;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.9
Committed:	Sat Jan 27 23:30:40 2001 UTC (23 years, 4 months ago) by tdb
Branch:	MAIN
Changes since 1.8:	+63 -22 lines
Log Message:	All of these classes have been javadoc'd and commented.
#	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	1.9	* @version $Id: TCPControlHandler.java,v 1.8 2001/01/24 00:55:33 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	1.9	public final String REVISION = "$Revision: 1.8 $";
32	tdb	1.1
33	tdb	1.9	/**
34			* This is our protocol version. It is hardcoded to ensure
35			* that it doesn't get accidently changed. A change to the
36			* protocol would also require changing this classes code !
37			*/
38	tdb	1.4	public static final String PROTOVER = "PROTOCOL 1.1";
39	tdb	1.1
40			//---STATIC METHODS---
41
42			//---CONSTRUCTORS---
43	tdb	1.9
44			/**
45			* Construct a new TCPControlHandler, and setup the reader
46			* and writer for the new Socket.
47			*
48			* @param socket The Socket connected to the new Client
49			* @param packetSorter A reference to the PacketSorter in the component
50			*/
51			public TCPControlHandler(Socket socket, PacketSorter packetSorter) throws IOException {
52	tdb	1.1	_socket = socket;
53	tdb	1.9	_packetSorter = packetSorter;
54			// setup the reader & writer
55	tdb	1.1	_socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
56			_socketOut = new PrintWriter(_socket.getOutputStream());
57	tdb	1.9	// set the default hostlist to "all host", for backward compatibility
58	tdb	1.4	_hostList = "";
59	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "created");
60			}
61
62			//---PUBLIC METHODS---
63	tdb	1.9
64			/**
65			* This method initiates the thread, setting things up, and then
66			* reading commands from the Client. It handles setting up of the
67			* DataHandler, and clean shutting down.
68			*/
69	tdb	1.1	public void run() {
70			boolean run = true;
71	tdb	1.9	// Tell the client our protocol, and ask it for it's name
72	tdb	1.1	try {
73			_socketOut.println(PROTOVER);
74			_socketOut.flush();
75			_clientName = _socketIn.readLine();
76			_socketOut.println("OK");
77			_socketOut.flush();
78			}
79			catch(IOException e) {
80			_logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
81			run=false;
82			}
83
84			_logger.write(toString(), Logger.SYSMSG, "Client has connected: "+_clientName);
85
86	tdb	1.9	// loop until we decide to shutdown (run=false)
87	tdb	1.1	while(run) {
88			try {
89			String cmd = _socketIn.readLine();
90	tdb	1.9	// make a decision about what to do
91	tdb	1.1	if(cmd.equals("STARTCONFIG")) {
92	tdb	1.9	// get the configuration for this client
93	tdb	1.1	Configuration myConfig = _configManager.getConfiguration("Client."+_clientName);
94			_socketOut.println("OK");
95			_socketOut.flush();
96			// get properties
97			cmd = _socketIn.readLine();
98	tdb	1.9	// provide all the requested properties
99	tdb	1.1	while(!cmd.equals("ENDCONFIG")) {
100	tdb	1.9	// client is restricted to this properties
101	tdb	1.7	if(cmd.startsWith("Client.") \|\| cmd.startsWith("Host.")) {
102			try {
103			String returnedProperty = myConfig.getProperty(cmd);
104			_socketOut.println(returnedProperty);
105			_socketOut.flush();
106			}
107			catch (org.omg.CORBA.MARSHAL e) {
108			_socketOut.println("ERROR");
109			_socketOut.flush();
110			}
111			}
112			else {
113	tdb	1.1	_socketOut.println("ERROR");
114			_socketOut.flush();
115			}
116			cmd = _socketIn.readLine();
117			}
118			_socketOut.println("OK");
119			_socketOut.flush();
120			_logger.write(toString(), Logger.SYSMSG, "Client has been configured");
121
122			}
123			else if(cmd.equals("STARTDATA")) {
124	tdb	1.9	// if we don't have a DataHandler, set one up
125	tdb	1.1	if(_dataHandler == null) {
126			// create a serversocket
127			ServerSocket ss = new ServerSocket(0);
128			// get the port
129			int port = ss.getLocalPort();
130	tdb	1.9	// tell the client the port
131	tdb	1.1	_socketOut.println(port);
132			_socketOut.flush();
133	tdb	1.9	// wait for the client to connect
134	tdb	1.1	Socket s = ss.accept();
135			// when we get the Socket back, give it to the data thread
136	tdb	1.4	TCPDataHandler dh = new TCPDataHandler(s);
137	tdb	1.9	// register the DataHandler's queue, giving the host list
138			_packetSorter.register(dh.getQueue(), _hostList);
139			// start up the DataHandler
140	tdb	1.2	dh.start();
141	tdb	1.9	// Hold a reference to the DataHandler, so we can stop it later
142	tdb	1.1	_dataHandler = dh;
143			_socketOut.println("OK");
144			_socketOut.flush();
145			_logger.write(toString(), Logger.SYSMSG, "Data stream started at Clients Request on port: "+port);
146			}
147			else {
148			_socketOut.println("ERROR");
149			_socketOut.flush();
150			}
151			}
152			else if(cmd.equals("STOPDATA")) {
153	tdb	1.9	// if we have a DataHandler, shut it down
154	tdb	1.1	if(_dataHandler != null) {
155	tdb	1.9	// Deregister the DataHandler, giving the host list
156			_packetSorter.deregister(_dataHandler.getQueue(), _hostList);
157	tdb	1.2	// Shut down the data handler
158	tdb	1.1	_dataHandler.shutdown();
159	tdb	1.9	// Destroy our reference, leaving it for the GC
160	tdb	1.1	_dataHandler = null;
161			_socketOut.println("OK");
162			_socketOut.flush();
163			_logger.write(toString(), Logger.SYSMSG, "Data stream stopped at Clients Request");
164			}
165			else {
166			_socketOut.println("ERROR");
167			_socketOut.flush();
168			}
169			}
170	tdb	1.4	else if(cmd.equals("SETHOSTLIST")) {
171	tdb	1.9	// we can only set the host list when
172			// the DataHandler is not connected
173	tdb	1.5	if(_dataHandler == null) {
174			_socketOut.println("OK");
175			_socketOut.flush();
176	tdb	1.9	// read and set the host list
177	tdb	1.5	cmd = _socketIn.readLine();
178			_hostList = cmd;
179			_socketOut.println("OK");
180			_socketOut.flush();
181			}
182			else {
183			_socketOut.println("ERROR");
184			_socketOut.flush();
185			}
186	tdb	1.4	}
187	tdb	1.2	else if(cmd.equals("DISCONNECT")) {
188	tdb	1.9	// we going to disconnect, so lets stop this loop
189	tdb	1.1	run=false;
190	tdb	1.9	// if there is a DataHandler, we'd best shut it down
191	tdb	1.3	if(_dataHandler != null) {
192	tdb	1.9	// Deregister the DataHandler, giving the host list
193			_packetSorter.deregister(_dataHandler.getQueue(), _hostList);
194	tdb	1.3	// Shut down the data handler
195			_dataHandler.shutdown();
196	tdb	1.9	// Destroy our reference, leaving it for the GC
197	tdb	1.3	_dataHandler = null;
198	tdb	1.8	_socketOut.println("OK");
199			_socketOut.flush();
200	tdb	1.3	_logger.write(toString(), Logger.SYSMSG, "Data stream stopped at Clients Request");
201			}
202	tdb	1.1	_socketOut.println("OK");
203			_socketOut.flush();
204	tdb	1.9	// close the reader, writer and Socket
205	tdb	1.1	_socketIn.close();
206			_socketOut.close();
207			_socket.close();
208			_logger.write(toString(), Logger.SYSMSG, "Closing at Clients Request");
209			}
210			else {
211			_socketOut.println("ERROR");
212			_socketOut.flush();
213			}
214			}
215			catch(IOException e) {
216	tdb	1.9	// if we get an exception, the client has probably left, so we stop
217	tdb	1.8	run=false;
218			_logger.write(toString(), Logger.FATAL, "Fatal communication error, shutdown pending");
219	tdb	1.1	}
220			}
221	tdb	1.8	_logger.write(toString(), Logger.SYSMSG, "Shutting down Control Handler, client has gone.");
222	tdb	1.1	}
223
224			/**
225			* Overrides the {@link java.lang.Object#toString() Object.toString()}
226			* method to provide clean logging (every class should have this).
227			*
228			* This uses the uk.ac.ukc.iscream.util.NameFormat class
229			* to format the toString()
230			*
231			* @return the name of this class and its CVS revision
232			*/
233			public String toString() {
234			return FormatName.getName(
235			_name,
236			getClass().getName(),
237			REVISION);
238			}
239
240			//---PRIVATE METHODS---
241
242			//---ACCESSOR/MUTATOR METHODS---
243
244			//---ATTRIBUTES---
245
246			/**
247			* This is the friendly identifier of the
248			* component this class is running in.
249			* eg, a Filter may be called "filter1",
250			* If this class does not have an owning
251			* component, a name from the configuration
252			* can be placed here. This name could also
253			* be changed to null for utility classes.
254			*/
255			private String _name = ClientInterfaceMain.NAME;
256
257			/**
258			* This holds a reference to the
259			* system logger that is being used.
260			*/
261			private Logger _logger = ReferenceManager.getInstance().getLogger();
262
263			/**
264			* A reference to the Configuration Manager the system is using
265			*/
266			private ConfigurationManager _configManager = ReferenceManager.getInstance().getCM();
267
268			/**
269			* The socket we are talking on
270			*/
271			private Socket _socket;
272
273			/**
274			* A hook to the inbound data from the socket
275			*/
276			private BufferedReader _socketIn;
277
278			/**
279			* A hook to the outbound stream for the socket
280			*/
281			private PrintWriter _socketOut;
282	tdb	1.4
283	tdb	1.1	/**
284	tdb	1.4	* A reference to the PacketSorter.
285			*/
286	tdb	1.9	private PacketSorter _packetSorter;
287	tdb	1.1
288	tdb	1.9	/**
289			* A reference to the DataHandler, if there is one
290			*/
291	tdb	1.1	private TCPDataHandler _dataHandler;
292
293	tdb	1.9	/**
294			* The name of the Client we're connected to
295			*/
296	tdb	1.1	private String _clientName;
297	tdb	1.9
298			/**
299			* The host list the Client has requested
300			*/
301	tdb	1.4	private String _hostList;
302	tdb	1.1
303			//---STATIC ATTRIBUTES---
304
305			}