cms/conient/ConnectionHandler.java

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

//---IMPORTS---
import uk.ac.ukc.iscream.util.*;
import java.io.*;
import java.net.*;
import javax.swing.JOptionPane;

/**
 * This is the main thread for the client.
 * Once started i continually checks it actionQueue
 * for actions that other areas of the system have placed 
 * there, it then performs those actions.
 *
 * Currently this is the main thread where all non-GUI events
 * are dispatched to.
 *
 * @author  $Author: tdb1 $
 * @version $Id: ConnectionHandler.java,v 1.9 2001/01/24 01:12:30 tdb1 Exp $
 */
public class ConnectionHandler extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.9 $";


    /**
     * The hardcoded protocol version that we are using.
     * Used when handshaking with the server
     */
    public final double PROTOCOL_VERSION = 1.0;

    /**
     * Thread action DONOTHING.
     * This is an invalid action, but here for completeness
     * if anything sends this action it will warn appropriately
     * but do what it says, ie, nothing ;)
     */
    public static final int DONOTHING = 0;
    
    /**
     * Thread action CONNECT.
     * Opens the control link to the i-scream server.
     */
    public static final int CONNECT = 1;
    
    /**
     * Thread action STARTDATA.
     * Opens the data link to the i-scream server
     * and prepares all gui data components for data
     * it then starts all relavant threads going.
     */
    public static final int STARTDATA = 2;
    
    /**
     * Thread action STOPDATA.
     * Closes the data link and shuts down all components
     * that update gui for various things.
     */
    public static final int STOPDATA = 3;
    
    /**
     * Thread action DISCONNECT.
     * Checks to see if STOPDATA has been called if not,
     * it will add STOPDATA and then DISCONNECT to
     * the action queue and return.  If STOPDATA has been
     * called it closes down the Control Link and tidies up
     * all relevant threads
     */
    public static final int DISCONNECT = 4;
    
    /**
     * Thread action QUIT.
     * Checks the status of the two links, if either
     * are still up, it queues the appropriate commands
     * to close them down.  It then System.exit(0)'s!
     */
    public static final int QUIT = 5;

//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Constructs new data handler.
     * Needs a reference to the data panel so that
     * it can set it processing inBound data
     * Also gets a reference to the queue that will be
     * used by other areas of the system to send it actions
     *
     * @param data the DataPanel in use
     * @param actionQueue the actionQueue for this class
     */ 
    public ConnectionHandler(DataPanel data, Queue actionQueue) {
        _data = data;
        _actionQueue = actionQueue;
        _myQueue = _actionQueue.getQueue();
    }
    
//---PUBLIC METHODS---


    /**
     * Starts this ConnectionHandler running.
     * This basically runs until told to stop, it gets "actions"
     * from its actionQueue and switch's on them do determine
     * what it should do it then carries out the action
     *
     * For details on what each action does see the action
     * types.
     */
    public void run() {
        while(_running) {
            // we wait for a call...
            int action = 0;
            try {
                action = ((Integer) _actionQueue.get(_myQueue)).intValue();
            } catch (InvalidQueueException e) {
                // we 're never going to get this...
            }
            
            // examine our action...
            // if it was to connect...then we connect...
            switch(action) {
                case CONNECT:
                
                    Object serverQuestion = null;
                    serverQuestion = JOptionPane.showInputDialog(null, "Please enter the name of a server running the I-Scream client interface:", "I-Scream Server", JOptionPane.INFORMATION_MESSAGE);
                    if (serverQuestion instanceof String) {
                        _server = (String) serverQuestion;
                        SwingClient.setControlStatus("Connecting to - " + _server);
                        try {
                            _controlLink = new Socket(_server, _port);
                            _inBound = new BufferedReader(new InputStreamReader(_controlLink.getInputStream()));
                            _outBound = new PrintWriter(_controlLink.getOutputStream());
                            SwingClient.setControlStatus("Connection Established - " + _server);
                            String response;
                            response = _inBound.readLine();
                            if (!(Double.parseDouble(response.substring(10, response.length())) > PROTOCOL_VERSION)) {
                                SwingClient.addMessage("WARNING: server is using a newer protocol (" + response + "), please update your client, continuing with old protocol (PROTOCOL " + PROTOCOL_VERSION + ")" );
                            } else if (!(Double.parseDouble(response.substring(10, response.length())) < PROTOCOL_VERSION)) {
                                throw new IOException("invalid protocol version");
                            }
                            SwingClient.addMessage("Handshake Success");
                            
                            // send the name - get from somewhere eventually
                            _outBound.println(_clientName);
                            _outBound.flush();
                            response = _inBound.readLine();
                            if (!response.equals("OK")) {
                                throw new IOException("client name rejected - " + response);
                            }
                            SwingClient.addMessage("Control Link Established");

                        } catch (IOException e) {
                            SwingClient.addMessage("Control Link Error: " + e);
                            SwingClient.setControlStatus("Disconnected");
                        }
                    }
                    break;
                case STARTDATA:
                    SwingClient.addMessage("Attempting to open Data Channel");
                    try {
                        if(_controlLink == null) {
                            _actionQueue.add(new Integer(CONNECT));
                            _actionQueue.add(new Integer(STARTDATA));
                            throw new IOException("Control Link not establised - queueing start events");
                        }
                        String response;
                        _outBound.println("STARTDATA");
                        _outBound.flush();
                        response = _inBound.readLine();
                        
                        // TEMPORARY FIREWALL FIX
                        // allows user to map an ssh pipe...
                        JOptionPane.showMessageDialog(null, "WARNING: about to connect to a port you may not have available!\nPlease ensure you have port \"" + response + "\" of your I-Scream server mapped to " + _server, "FIREWALL WARNING!", JOptionPane.INFORMATION_MESSAGE);
                        SwingClient.setDataStatus("Connecting to - " + _server + ":" + response);
                        try {
                            _dataLink = new Socket(_server, Integer.parseInt(response));
                        } catch (NumberFormatException e) {
                            throw new IOException("error, invalid data port suggested by server - " + response);
                        }
                        
                        response = _inBound.readLine();
                        if (!response.equals("OK")) {
                            throw new IOException("server reported error establishing data channel - " + response);
                        }
                        _dataInBound = new BufferedReader(new InputStreamReader(_dataLink.getInputStream()));
                        _dataOutBound = new PrintWriter(_dataLink.getOutputStream());
                        SwingClient.setDataStatus("Connection Established - " + _server);
                        SwingClient.addMessage("Data Link connection established");
                        SwingClient.addMessage("Starting data reader");

                        // here we will do some connect stuff.
                        Queue theQueue = new Queue();
                        _dataReader = new DataReader(_dataInBound, theQueue);
                        _data.setQueue(theQueue);
                        _data.cleanUpTabs();
                        new Thread(_data).start();
                        _dataReader.start();
                        // finished for us....
                    } catch (IOException e) {
                        SwingClient.addMessage("Data Link Error: " + e);
                        SwingClient.setDataStatus("Disconnected");
                    }
                    break;
                case STOPDATA:
                    SwingClient.addMessage("Attempting to close Data Channel");
                    try {
                        String response;
                        _outBound.println("STOPDATA");
                        _outBound.flush();
                        response = _inBound.readLine();
                        if (!response.equals("OK")) {
                            throw new IOException("server didn't OK request to stop data channel");
                        }
                        // kill the data reader - we should wait
                        // for it to die nicely...but we won't yet...we'll kill the socket! ;-p
                        SwingClient.setDataStatus("Disconnecting - " + _server);
                        _dataReader.shutdown();
                        _dataInBound.close();
                        _dataOutBound.close();
                        _dataLink.close();
                        // get rid of the socket
                        _dataLink = null;
                        SwingClient.setDataStatus("Disconnected");
                        SwingClient.addMessage("Data Channel closed");
                    } catch (IOException e) {
                        SwingClient.addMessage("Data Link Error: " + e);
                        SwingClient.setDataStatus("Unknown");
                    }
                    break;
                case DISCONNECT:
                    SwingClient.addMessage("Attempting to close Control Channel");
                    try {
                        if (_dataLink != null) {
                            // we want to tell ourselves to stop it
                            _actionQueue.add(new Integer(STOPDATA));
                            _actionQueue.add(new Integer(DISCONNECT));
                            throw new IOException("Warning - Data Channel not closed - attempting to close it!");
                        }
                        String response;
                        _outBound.println("DISCONNECT");
                        _outBound.flush();
                        response = _inBound.readLine();
                        if (!response.equals("OK")) {
                            throw new IOException("server didn't OK request to stop control channel");
                        }
                        // then lets go!
                        SwingClient.setControlStatus("Disconnecting - " + _server);
                        _inBound.close();
                        _outBound.close();
                        _controlLink.close();
                        // for good measure
                        _controlLink = null;
                        SwingClient.setControlStatus("Disconnected");
                    } catch (IOException e) {
                        SwingClient.addMessage("Control Link Error: " + e);
                        SwingClient.setControlStatus("Unknown");
                    }
                    break;
                case QUIT:
                    SwingClient.addMessage("Exiting...");
                    try {
                        // stop data and control if data up
                        if (_dataLink != null) {
                            _actionQueue.add(new Integer(STOPDATA));
                            _actionQueue.add(new Integer(DISCONNECT));
                            _actionQueue.add(new Integer(QUIT));
                            throw new IOException();
                        }                            
                        // stop control
                        if (_controlLink != null) {
                            _actionQueue.add(new Integer(DISCONNECT));
                            _actionQueue.add(new Integer(QUIT));
                            throw new IOException();
                        }
                        SwingClient.addMessage("Finished.");
                        // go!
                        System.exit(0);
                    } catch (IOException e) {
                        SwingClient.addMessage("Closing connections...");
                    }
                    break;
            }
        }
    }
    
//---PRIVATE METHODS---

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

//---ATTRIBUTES---       

    boolean _running = true;
    SwingClient SwingClient;
    DataPanel _data;
    Queue _actionQueue;
    int _myQueue;
    String _server;
    int _port = SwingClient.PORT;
    Socket _controlLink;
    Socket _dataLink;
    BufferedReader _inBound;
    PrintWriter _outBound;
    BufferedReader _dataInBound;
    PrintWriter _dataOutBound;
    DataReader _dataReader;
    String _clientName = "Conient";

//---STATIC ATTRIBUTES---

}
Revision:	1.10
Committed:	Wed Jan 24 03:09:46 2001 UTC (23 years, 4 months ago) by ajm
Branch:	MAIN
Changes since 1.9:	+6 -5 lines
Log Message:	all packaged up all javadoc'd still not handling stuff (sockets) right just yet.... but its all in a fit state to be PROPER and continue working and expanding on
#	Content
1	//---PACKAGE DECLARATION---
2	package uk.ac.ukc.iscream.conient;
3
4	//---IMPORTS---
5	import uk.ac.ukc.iscream.util.*;
6	import java.io.*;
7	import java.net.*;
8	import javax.swing.JOptionPane;
9
10	/**
11	* This is the main thread for the client.
12	* Once started i continually checks it actionQueue
13	* for actions that other areas of the system have placed
14	* there, it then performs those actions.
15	*
16	* Currently this is the main thread where all non-GUI events
17	* are dispatched to.
18	*
19	* @author $Author: tdb1 $
20	* @version $Id: ConnectionHandler.java,v 1.9 2001/01/24 01:12:30 tdb1 Exp $
21	*/
22	public class ConnectionHandler extends Thread {
23
24	//---FINAL ATTRIBUTES---
25
26	/**
27	* The current CVS revision of this class
28	*/
29	public final String REVISION = "$Revision: 1.9 $";
30
31
32	/**
33	* The hardcoded protocol version that we are using.
34	* Used when handshaking with the server
35	*/
36	public final double PROTOCOL_VERSION = 1.0;
37
38	/**
39	* Thread action DONOTHING.
40	* This is an invalid action, but here for completeness
41	* if anything sends this action it will warn appropriately
42	* but do what it says, ie, nothing ;)
43	*/
44	public static final int DONOTHING = 0;
45
46	/**
47	* Thread action CONNECT.
48	* Opens the control link to the i-scream server.
49	*/
50	public static final int CONNECT = 1;
51
52	/**
53	* Thread action STARTDATA.
54	* Opens the data link to the i-scream server
55	* and prepares all gui data components for data
56	* it then starts all relavant threads going.
57	*/
58	public static final int STARTDATA = 2;
59
60	/**
61	* Thread action STOPDATA.
62	* Closes the data link and shuts down all components
63	* that update gui for various things.
64	*/
65	public static final int STOPDATA = 3;
66
67	/**
68	* Thread action DISCONNECT.
69	* Checks to see if STOPDATA has been called if not,
70	* it will add STOPDATA and then DISCONNECT to
71	* the action queue and return. If STOPDATA has been
72	* called it closes down the Control Link and tidies up
73	* all relevant threads
74	*/
75	public static final int DISCONNECT = 4;
76
77	/**
78	* Thread action QUIT.
79	* Checks the status of the two links, if either
80	* are still up, it queues the appropriate commands
81	* to close them down. It then System.exit(0)'s!
82	*/
83	public static final int QUIT = 5;
84
85	//---STATIC METHODS---
86
87	//---CONSTRUCTORS---
88
89	/**
90	* Constructs new data handler.
91	* Needs a reference to the data panel so that
92	* it can set it processing inBound data
93	* Also gets a reference to the queue that will be
94	* used by other areas of the system to send it actions
95	*
96	* @param data the DataPanel in use
97	* @param actionQueue the actionQueue for this class
98	*/
99	public ConnectionHandler(DataPanel data, Queue actionQueue) {
100	_data = data;
101	_actionQueue = actionQueue;
102	_myQueue = _actionQueue.getQueue();
103	}
104
105	//---PUBLIC METHODS---
106
107
108	/**
109	* Starts this ConnectionHandler running.
110	* This basically runs until told to stop, it gets "actions"
111	* from its actionQueue and switch's on them do determine
112	* what it should do it then carries out the action
113	*
114	* For details on what each action does see the action
115	* types.
116	*/
117	public void run() {
118	while(_running) {
119	// we wait for a call...
120	int action = 0;
121	try {
122	action = ((Integer) _actionQueue.get(_myQueue)).intValue();
123	} catch (InvalidQueueException e) {
124	// we 're never going to get this...
125	}
126
127	// examine our action...
128	// if it was to connect...then we connect...
129	switch(action) {
130	case CONNECT:
131
132	Object serverQuestion = null;
133	serverQuestion = JOptionPane.showInputDialog(null, "Please enter the name of a server running the I-Scream client interface:", "I-Scream Server", JOptionPane.INFORMATION_MESSAGE);
134	if (serverQuestion instanceof String) {
135	_server = (String) serverQuestion;
136	SwingClient.setControlStatus("Connecting to - " + _server);
137	try {
138	_controlLink = new Socket(_server, _port);
139	_inBound = new BufferedReader(new InputStreamReader(_controlLink.getInputStream()));
140	_outBound = new PrintWriter(_controlLink.getOutputStream());
141	SwingClient.setControlStatus("Connection Established - " + _server);
142	String response;
143	response = _inBound.readLine();
144	if (!(Double.parseDouble(response.substring(10, response.length())) > PROTOCOL_VERSION)) {
145	SwingClient.addMessage("WARNING: server is using a newer protocol (" + response + "), please update your client, continuing with old protocol (PROTOCOL " + PROTOCOL_VERSION + ")" );
146	} else if (!(Double.parseDouble(response.substring(10, response.length())) < PROTOCOL_VERSION)) {
147	throw new IOException("invalid protocol version");
148	}
149	SwingClient.addMessage("Handshake Success");
150
151	// send the name - get from somewhere eventually
152	_outBound.println(_clientName);
153	_outBound.flush();
154	response = _inBound.readLine();
155	if (!response.equals("OK")) {
156	throw new IOException("client name rejected - " + response);
157	}
158	SwingClient.addMessage("Control Link Established");
159
160	} catch (IOException e) {
161	SwingClient.addMessage("Control Link Error: " + e);
162	SwingClient.setControlStatus("Disconnected");
163	}
164	}
165	break;
166	case STARTDATA:
167	SwingClient.addMessage("Attempting to open Data Channel");
168	try {
169	if(_controlLink == null) {
170	_actionQueue.add(new Integer(CONNECT));
171	_actionQueue.add(new Integer(STARTDATA));
172	throw new IOException("Control Link not establised - queueing start events");
173	}
174	String response;
175	_outBound.println("STARTDATA");
176	_outBound.flush();
177	response = _inBound.readLine();
178
179	// TEMPORARY FIREWALL FIX
180	// allows user to map an ssh pipe...
181	JOptionPane.showMessageDialog(null, "WARNING: about to connect to a port you may not have available!\nPlease ensure you have port \"" + response + "\" of your I-Scream server mapped to " + _server, "FIREWALL WARNING!", JOptionPane.INFORMATION_MESSAGE);
182	SwingClient.setDataStatus("Connecting to - " + _server + ":" + response);
183	try {
184	_dataLink = new Socket(_server, Integer.parseInt(response));
185	} catch (NumberFormatException e) {
186	throw new IOException("error, invalid data port suggested by server - " + response);
187	}
188
189	response = _inBound.readLine();
190	if (!response.equals("OK")) {
191	throw new IOException("server reported error establishing data channel - " + response);
192	}
193	_dataInBound = new BufferedReader(new InputStreamReader(_dataLink.getInputStream()));
194	_dataOutBound = new PrintWriter(_dataLink.getOutputStream());
195	SwingClient.setDataStatus("Connection Established - " + _server);
196	SwingClient.addMessage("Data Link connection established");
197	SwingClient.addMessage("Starting data reader");
198
199	// here we will do some connect stuff.
200	Queue theQueue = new Queue();
201	_dataReader = new DataReader(_dataInBound, theQueue);
202	_data.setQueue(theQueue);
203	_data.cleanUpTabs();
204	new Thread(_data).start();
205	_dataReader.start();
206	// finished for us....
207	} catch (IOException e) {
208	SwingClient.addMessage("Data Link Error: " + e);
209	SwingClient.setDataStatus("Disconnected");
210	}
211	break;
212	case STOPDATA:
213	SwingClient.addMessage("Attempting to close Data Channel");
214	try {
215	String response;
216	_outBound.println("STOPDATA");
217	_outBound.flush();
218	response = _inBound.readLine();
219	if (!response.equals("OK")) {
220	throw new IOException("server didn't OK request to stop data channel");
221	}
222	// kill the data reader - we should wait
223	// for it to die nicely...but we won't yet...we'll kill the socket! ;-p
224	SwingClient.setDataStatus("Disconnecting - " + _server);
225	_dataReader.shutdown();
226	_dataInBound.close();
227	_dataOutBound.close();
228	_dataLink.close();
229	// get rid of the socket
230	_dataLink = null;
231	SwingClient.setDataStatus("Disconnected");
232	SwingClient.addMessage("Data Channel closed");
233	} catch (IOException e) {
234	SwingClient.addMessage("Data Link Error: " + e);
235	SwingClient.setDataStatus("Unknown");
236	}
237	break;
238	case DISCONNECT:
239	SwingClient.addMessage("Attempting to close Control Channel");
240	try {
241	if (_dataLink != null) {
242	// we want to tell ourselves to stop it
243	_actionQueue.add(new Integer(STOPDATA));
244	_actionQueue.add(new Integer(DISCONNECT));
245	throw new IOException("Warning - Data Channel not closed - attempting to close it!");
246	}
247	String response;
248	_outBound.println("DISCONNECT");
249	_outBound.flush();
250	response = _inBound.readLine();
251	if (!response.equals("OK")) {
252	throw new IOException("server didn't OK request to stop control channel");
253	}
254	// then lets go!
255	SwingClient.setControlStatus("Disconnecting - " + _server);
256	_inBound.close();
257	_outBound.close();
258	_controlLink.close();
259	// for good measure
260	_controlLink = null;
261	SwingClient.setControlStatus("Disconnected");
262	} catch (IOException e) {
263	SwingClient.addMessage("Control Link Error: " + e);
264	SwingClient.setControlStatus("Unknown");
265	}
266	break;
267	case QUIT:
268	SwingClient.addMessage("Exiting...");
269	try {
270	// stop data and control if data up
271	if (_dataLink != null) {
272	_actionQueue.add(new Integer(STOPDATA));
273	_actionQueue.add(new Integer(DISCONNECT));
274	_actionQueue.add(new Integer(QUIT));
275	throw new IOException();
276	}
277	// stop control
278	if (_controlLink != null) {
279	_actionQueue.add(new Integer(DISCONNECT));
280	_actionQueue.add(new Integer(QUIT));
281	throw new IOException();
282	}
283	SwingClient.addMessage("Finished.");
284	// go!
285	System.exit(0);
286	} catch (IOException e) {
287	SwingClient.addMessage("Closing connections...");
288	}
289	break;
290	}
291	}
292	}
293
294	//---PRIVATE METHODS---
295
296	//---ACCESSOR/MUTATOR METHODS---
297
298	//---ATTRIBUTES---
299
300	boolean _running = true;
301	SwingClient SwingClient;
302	DataPanel _data;
303	Queue _actionQueue;
304	int _myQueue;
305	String _server;
306	int _port = SwingClient.PORT;
307	Socket _controlLink;
308	Socket _dataLink;
309	BufferedReader _inBound;
310	PrintWriter _outBound;
311	BufferedReader _dataInBound;
312	PrintWriter _dataOutBound;
313	DataReader _dataReader;
314	String _clientName = "Conient";
315
316	//---STATIC ATTRIBUTES---
317
318	}