server/clientinterface/TCPControlHandler.java

//---PACKAGE DECLARATION---
package uk.org.iscream.clientinterface;

//---IMPORTS---
import uk.org.iscream.util.*;
import uk.org.iscream.componentmanager.*;
import uk.org.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 1.19 2001/03/13 18:37:08 tdb1 Exp $
 */
class TCPControlHandler extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.19 $";
    
    /**
     * 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 {
        // set the Thread name
        setName("clientinterface.TCPControlHandler");
        
        _socket = socket;
        _packetSorter = packetSorter;
        // setup the reader & writer
        _socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
        _socketOut = new PrintWriter(_socket.getOutputStream(), true);
        // 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 {
            send(PROTOVER);
            _clientName = _socketIn.readLine();
            if(_clientName==null) {
                throw new IOException("Fatal error reading from client");
            }
            sendOK();
        }
        catch(IOException e) {
            _logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
            run=false;
        }
        
        _logger.write(toString(), Logger.DEBUG, "Client has connected: "+_clientName);
        
        // loop until we decide to shutdown (run=false)
        while(run) {
            try {
                String cmd = _socketIn.readLine();
                if(cmd==null) {
                    throw new IOException("Fatal error reading from client");
                }
                // make a decision about what to do
                if(cmd.equals("STARTCONFIG")) {
                    // get the configuration for this client
                    Configuration myConfig = _configManager.getConfiguration("Client."+_clientName);
                    sendOK();
                    // get properties
                    cmd = _socketIn.readLine();
                    if(cmd==null) {
                        throw new IOException("Fatal error reading from client");
                    }
                    // 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);    
                                send(returnedProperty);
                            }
                            catch (org.omg.CORBA.MARSHAL e) {
                                sendERROR();
                            }
                        }
                        else {
                            sendERROR();
                        }
                        cmd = _socketIn.readLine();
                        if(cmd==null) {
                            throw new IOException("Fatal error reading from client");
                        }
                    }
                    sendOK();
                    _logger.write(toString(), Logger.DEBUG, "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
                        String port = new Integer(ss.getLocalPort()).toString();
                        // tell the client the port
                        send(port);
                        // 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);
                        try {
                            // startup a monitor on the DataHandler's queue
                            ConfigurationProxy cp = ConfigurationProxy.getInstance();
                            int queueMonitorInterval = Integer.parseInt(cp.getProperty("ClientInterface", "Queue.MonitorInterval"));
                            String queueName = _name + " TCPHandler:"+_socket.getInetAddress().getHostName();
                            dh.getQueue().startMonitor(queueMonitorInterval*1000, _packetSorter.getQueue(), queueName);
                        } catch (PropertyNotFoundException e) {
                            _logger.write(toString(), Logger.WARNING, "failed to find queue monitor config, disabling. " + e);
                        }
                        // start up the DataHandler
                        dh.start();
                        // Hold a reference to the DataHandler, so we can stop it later
                        _dataHandler = dh;
                        sendOK();
                        _logger.write(toString(), Logger.DEBUG, "Data stream started at Clients Request on port: "+port);
                    }
                    else {
                        sendERROR();
                    }
                }
                else if(cmd.equals("STOPDATA")) {
                    // attempt to close the data channel
                    if(closeData()) {
                        sendOK();
                        _logger.write(toString(), Logger.DEBUG, "Data stream stopped at Clients Request");
                    }
                    else {
                        sendERROR();
                    }
                }
                else if(cmd.equals("SETHOSTLIST")) {
                    // we can only set the host list when
                    // the DataHandler is not connected
                    if(_dataHandler == null) {
                        sendOK();
                        // read and set the host list
                        cmd = _socketIn.readLine();
                        if(cmd==null) {
                            throw new IOException("Fatal error reading from client");
                        }
                        _hostList = cmd;
                        sendOK();
                    }
                    else {
                        sendERROR();
                    }
                }
                else if(cmd.equals("DISCONNECT")) {
                    // we going to disconnect, so lets stop the main loop
                    run=false;
                    // if there is a DataHandler, we'd best shut it down
                    if(closeData()) {
                        _logger.write(toString(), Logger.DEBUG, "Data stream stopped at Clients Request");
                    }
                    // say bye to the client
                    sendOK();
                    // close the reader, writer and Socket
                    _socketIn.close();
                    _socketOut.close();
                    _socket.close();
                    _logger.write(toString(), Logger.DEBUG, "Closing at Clients Request");
                }
                else {
                    sendERROR();
                }
            }
            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");
            }
        }
        // we'll close any DataHandlers here that shouldn't be open still
        if(closeData()) {
            _logger.write(toString(), Logger.DEBUG, "Data stream stopped due to fatal client error");
        }
        _logger.write(toString(), Logger.DEBUG, "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.org.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---

    /**
     * Attempt to close down the DataHandler. This will return
     * true if it managed to close it down, or false if there
     * wasn't a DataHandler to close.
     *
     * @return whether the channel could be closed
     */
    private boolean closeData() {
        // 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;
            return true;
        }
        else {
            return false;
        }
    }
    
    /**
     * Send an OK message to the outgoing Socket
     */
    private void sendOK() {
        send("OK");
    }
    
    /**
     * Send an ERROR message to the outgoing Socket.
     */
    private void sendERROR() {
        send("ERROR");
    }
    
    /**
     * Send any String message to the outgoing Socket.
     *
     * @param message The message/command to send.
     */
    private void send(String message) {
        _socketOut.println(message);
    }

//---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:	1.20
Committed:	Wed Mar 14 23:25:29 2001 UTC (24 years, 8 months ago) by tdb
Branch:	MAIN
Changes since 1.19:	+7 -7 lines
Log Message:	The whole server package structure has been changed. Old Package: uk.ac.ukc.iscream.* New Package: uk.org.iscream.*
#	Content
1	//---PACKAGE DECLARATION---
2	package uk.org.iscream.clientinterface;
3
4	//---IMPORTS---
5	import uk.org.iscream.util.*;
6	import uk.org.iscream.componentmanager.*;
7	import uk.org.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	* @author $Author: tdb1 $
22	* @version $Id: TCPControlHandler.java,v 1.19 2001/03/13 18:37:08 tdb1 Exp $
23	*/
24	class TCPControlHandler extends Thread {
25
26	//---FINAL ATTRIBUTES---
27
28	/**
29	* The current CVS revision of this class
30	*/
31	public final String REVISION = "$Revision: 1.19 $";
32
33	/**
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	public static final String PROTOVER = "PROTOCOL 1.1";
39
40	//---STATIC METHODS---
41
42	//---CONSTRUCTORS---
43
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	// set the Thread name
53	setName("clientinterface.TCPControlHandler");
54
55	_socket = socket;
56	_packetSorter = packetSorter;
57	// setup the reader & writer
58	_socketIn = new BufferedReader(new InputStreamReader(_socket.getInputStream()));
59	_socketOut = new PrintWriter(_socket.getOutputStream(), true);
60	// set the default hostlist to "all host", for backward compatibility
61	_hostList = "";
62	_logger.write(toString(), Logger.SYSINIT, "created");
63	}
64
65	//---PUBLIC METHODS---
66
67	/**
68	* This method initiates the thread, setting things up, and then
69	* reading commands from the Client. It handles setting up of the
70	* DataHandler, and clean shutting down.
71	*/
72	public void run() {
73	boolean run = true;
74	// Tell the client our protocol, and ask it for it's name
75	try {
76	send(PROTOVER);
77	_clientName = _socketIn.readLine();
78	if(_clientName==null) {
79	throw new IOException("Fatal error reading from client");
80	}
81	sendOK();
82	}
83	catch(IOException e) {
84	_logger.write(toString(), Logger.FATAL, "Fatal error, shutdown pending");
85	run=false;
86	}
87
88	_logger.write(toString(), Logger.DEBUG, "Client has connected: "+_clientName);
89
90	// loop until we decide to shutdown (run=false)
91	while(run) {
92	try {
93	String cmd = _socketIn.readLine();
94	if(cmd==null) {
95	throw new IOException("Fatal error reading from client");
96	}
97	// make a decision about what to do
98	if(cmd.equals("STARTCONFIG")) {
99	// get the configuration for this client
100	Configuration myConfig = _configManager.getConfiguration("Client."+_clientName);
101	sendOK();
102	// get properties
103	cmd = _socketIn.readLine();
104	if(cmd==null) {
105	throw new IOException("Fatal error reading from client");
106	}
107	// provide all the requested properties
108	while(!cmd.equals("ENDCONFIG")) {
109	// client is restricted to this properties
110	if(cmd.startsWith("Client.") \|\| cmd.startsWith("Host.")) {
111	try {
112	String returnedProperty = myConfig.getProperty(cmd);
113	send(returnedProperty);
114	}
115	catch (org.omg.CORBA.MARSHAL e) {
116	sendERROR();
117	}
118	}
119	else {
120	sendERROR();
121	}
122	cmd = _socketIn.readLine();
123	if(cmd==null) {
124	throw new IOException("Fatal error reading from client");
125	}
126	}
127	sendOK();
128	_logger.write(toString(), Logger.DEBUG, "Client has been configured");
129
130	}
131	else if(cmd.equals("STARTDATA")) {
132	// if we don't have a DataHandler, set one up
133	if(_dataHandler == null) {
134	// create a serversocket
135	ServerSocket ss = new ServerSocket(0);
136	// get the port
137	String port = new Integer(ss.getLocalPort()).toString();
138	// tell the client the port
139	send(port);
140	// wait for the client to connect
141	Socket s = ss.accept();
142	// when we get the Socket back, give it to the data thread
143	TCPDataHandler dh = new TCPDataHandler(s);
144	// register the DataHandler's queue, giving the host list
145	_packetSorter.register(dh.getQueue(), _hostList);
146	try {
147	// startup a monitor on the DataHandler's queue
148	ConfigurationProxy cp = ConfigurationProxy.getInstance();
149	int queueMonitorInterval = Integer.parseInt(cp.getProperty("ClientInterface", "Queue.MonitorInterval"));
150	String queueName = _name + " TCPHandler:"+_socket.getInetAddress().getHostName();
151	dh.getQueue().startMonitor(queueMonitorInterval*1000, _packetSorter.getQueue(), queueName);
152	} catch (PropertyNotFoundException e) {
153	_logger.write(toString(), Logger.WARNING, "failed to find queue monitor config, disabling. " + e);
154	}
155	// start up the DataHandler
156	dh.start();
157	// Hold a reference to the DataHandler, so we can stop it later
158	_dataHandler = dh;
159	sendOK();
160	_logger.write(toString(), Logger.DEBUG, "Data stream started at Clients Request on port: "+port);
161	}
162	else {
163	sendERROR();
164	}
165	}
166	else if(cmd.equals("STOPDATA")) {
167	// attempt to close the data channel
168	if(closeData()) {
169	sendOK();
170	_logger.write(toString(), Logger.DEBUG, "Data stream stopped at Clients Request");
171	}
172	else {
173	sendERROR();
174	}
175	}
176	else if(cmd.equals("SETHOSTLIST")) {
177	// we can only set the host list when
178	// the DataHandler is not connected
179	if(_dataHandler == null) {
180	sendOK();
181	// read and set the host list
182	cmd = _socketIn.readLine();
183	if(cmd==null) {
184	throw new IOException("Fatal error reading from client");
185	}
186	_hostList = cmd;
187	sendOK();
188	}
189	else {
190	sendERROR();
191	}
192	}
193	else if(cmd.equals("DISCONNECT")) {
194	// we going to disconnect, so lets stop the main loop
195	run=false;
196	// if there is a DataHandler, we'd best shut it down
197	if(closeData()) {
198	_logger.write(toString(), Logger.DEBUG, "Data stream stopped at Clients Request");
199	}
200	// say bye to the client
201	sendOK();
202	// close the reader, writer and Socket
203	_socketIn.close();
204	_socketOut.close();
205	_socket.close();
206	_logger.write(toString(), Logger.DEBUG, "Closing at Clients Request");
207	}
208	else {
209	sendERROR();
210	}
211	}
212	catch(IOException e) {
213	// if we get an exception, the client has probably left, so we stop
214	run=false;
215	_logger.write(toString(), Logger.FATAL, "Fatal communication error, shutdown pending");
216	}
217	}
218	// we'll close any DataHandlers here that shouldn't be open still
219	if(closeData()) {
220	_logger.write(toString(), Logger.DEBUG, "Data stream stopped due to fatal client error");
221	}
222	_logger.write(toString(), Logger.DEBUG, "Shutting down Control Handler, client has gone.");
223	}
224
225	/**
226	* Overrides the {@link java.lang.Object#toString() Object.toString()}
227	* method to provide clean logging (every class should have this).
228	*
229	* This uses the uk.org.iscream.util.NameFormat class
230	* to format the toString()
231	*
232	* @return the name of this class and its CVS revision
233	*/
234	public String toString() {
235	return FormatName.getName(
236	_name,
237	getClass().getName(),
238	REVISION);
239	}
240
241	//---PRIVATE METHODS---
242
243	/**
244	* Attempt to close down the DataHandler. This will return
245	* true if it managed to close it down, or false if there
246	* wasn't a DataHandler to close.
247	*
248	* @return whether the channel could be closed
249	*/
250	private boolean closeData() {
251	// if we have a DataHandler, shut it down
252	if(_dataHandler != null) {
253	// Deregister the DataHandler, giving the host list
254	_packetSorter.deregister(_dataHandler.getQueue(), _hostList);
255	// Shut down the data handler
256	_dataHandler.shutdown();
257	// Destroy our reference, leaving it for the GC
258	_dataHandler = null;
259	return true;
260	}
261	else {
262	return false;
263	}
264	}
265
266	/**
267	* Send an OK message to the outgoing Socket
268	*/
269	private void sendOK() {
270	send("OK");
271	}
272
273	/**
274	* Send an ERROR message to the outgoing Socket.
275	*/
276	private void sendERROR() {
277	send("ERROR");
278	}
279
280	/**
281	* Send any String message to the outgoing Socket.
282	*
283	* @param message The message/command to send.
284	*/
285	private void send(String message) {
286	_socketOut.println(message);
287	}
288
289	//---ACCESSOR/MUTATOR METHODS---
290
291	//---ATTRIBUTES---
292
293	/**
294	* This is the friendly identifier of the
295	* component this class is running in.
296	* eg, a Filter may be called "filter1",
297	* If this class does not have an owning
298	* component, a name from the configuration
299	* can be placed here. This name could also
300	* be changed to null for utility classes.
301	*/
302	private String _name = ClientInterfaceMain.NAME;
303
304	/**
305	* This holds a reference to the
306	* system logger that is being used.
307	*/
308	private Logger _logger = ReferenceManager.getInstance().getLogger();
309
310	/**
311	* A reference to the Configuration Manager the system is using
312	*/
313	private ConfigurationManager _configManager = ReferenceManager.getInstance().getCM();
314
315	/**
316	* The socket we are talking on
317	*/
318	private Socket _socket;
319
320	/**
321	* A hook to the inbound data from the socket
322	*/
323	private BufferedReader _socketIn;
324
325	/**
326	* A hook to the outbound stream for the socket
327	*/
328	private PrintWriter _socketOut;
329
330	/**
331	* A reference to the PacketSorter.
332	*/
333	private PacketSorter _packetSorter;
334
335	/**
336	* A reference to the DataHandler, if there is one
337	*/
338	private TCPDataHandler _dataHandler;
339
340	/**
341	* The name of the Client we're connected to
342	*/
343	private String _clientName;
344
345	/**
346	* The host list the Client has requested
347	*/
348	private String _hostList;
349
350	//---STATIC ATTRIBUTES---
351
352	}