server/clientinterface/CorbaDataHandler.java

/* 
 * i-scream central monitoring system
 * http://www.i-scream.org.uk
 * Copyright (C) 2000-2002 i-scream
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

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

//---IMPORTS---
import uk.org.iscream.cms.util.*;
import uk.org.iscream.cms.server.componentmanager.*;
import uk.org.iscream.cms.server.core.*;
import uk.org.iscream.cms.server.client.*;


/**
 * Acts as a Data Handler to a CORBA based client.
 *
 * @author  $Author: tdb $
 * @version $Id: CorbaDataHandler.java,v 1.13 2002/05/21 16:47:16 tdb Exp $
 */
class CorbaDataHandler extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.13 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---
    
    /**
     * Construct a new CorbaDataHandler.
     *
     * @param client A reference to the "servant" part of the connecting client.
     * @param cchServer A reference to the class that is control us.
     */
    public CorbaDataHandler(Client client, CorbaControlHandlerServant cchServant) {
        // set the Thread name
        setName("clientinterface.CorbaDataHandler");
        
        ConfigurationProxy cp = ConfigurationProxy.getInstance();
        String configName = "ClientInterface";
        // see if this Queue needs a size limit
        try {
            int queueSizeLimit = Integer.parseInt(cp.getProperty(configName, "Queue.SizeLimit"));
            String queueRemoveAlgorithm = cp.getProperty(configName, "Queue.RemoveAlgorithm");
            int algorithm = StringUtils.getStringPos(queueRemoveAlgorithm, Queue.algorithms);
            if(algorithm != -1) {
                _logger.write(toString(), Logger.DEBUG, "Starting Queue with size limit of "+queueSizeLimit+", using remove algorithm "+queueRemoveAlgorithm);
                // we have valid values, so lets start it.
                _queue = new Queue(queueSizeLimit, algorithm);
            }
            else {
                _logger.write(toString(), Logger.WARNING, "Bad Queue Algorithm configuration, not known: "+queueRemoveAlgorithm);
                // just don't activate a limit
                _queue = new Queue();
            }
            
        } catch (PropertyNotFoundException e) {
            _logger.write(toString(), Logger.DEBUG, "Optional config not set: "+e);
            // just don't activate a limit
            _queue = new Queue();
        } catch (NumberFormatException e) {
            _logger.write(toString(), Logger.WARNING, "Bad Queue SizeLimit configuration: "+e);
            // just don't activate a limit
            _queue = new Queue();
        }

        _client = client;
        _cchServant = cchServant;
        _logger.write(toString(), Logger.SYSINIT, "created");
    }
    
//---PUBLIC METHODS---
    
    /**
     * This method loops round until such a point as we shutdown. It keeps
     * grabbing data items from it's Queue, then sends them on to the connected
     * client over CORBA.
     */
    public void run() {
        // get a queue
        _queueID = _queue.getQueue();
        // we'll keep going until someone implements a "shutdown" :)
        run = true;
        // loop sending data
        while(run) {
            try {
                String xml = (String) _queue.get(_queueID);
                // if it's not null (which could happen if we're "released")
                // send it on to the client that we're connected to.
                if(xml != null) {
                    try {
                        _client.receiveXML(xml);
                    }
                    catch (org.omg.CORBA.COMM_FAILURE e) {
                        // lets stop sending, the client has quit
                        run = false;
                        _logger.write(toString(), Logger.ERROR, "Connection failure (COMM_FAILURE), client shutdown? : "+e);
                    }
                    catch (org.omg.CORBA.TRANSIENT e) {
                        // lets stop sending, the client has quit
                        run = false;
                        _logger.write(toString(), Logger.ERROR, "Connection failure (TRANSIENT), client shutdown? : "+e);
                    }
                }
            }
            catch(InvalidQueueException e) {
                // lets stop sending.
                run = false;
                _logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
            }
        }
        // disconnect the servant above us, or at least try
        _cchServant.disconnect();
        // if we get here we've been told to stop
        _logger.write(toString(), Logger.SYSMSG, "Shutting Down");
        // remove ourselves from the queue
        _queue.removeQueue(_queueID);
        _queue.stopMonitor();
    }
    
    /**
     * Method to shutdown this Data Handler. All this actually does
     * is set a flag which the main loop will see and commence shutting
     * down. This method will return before the main loop stops.
     */
    public void shutdown() {
        // set the main loop to stop
        run=false;
        // if the main loop is waiting for data it won't notice the
        // above flag to stop. This bumps it out of the blocked get.
        _queue.releaseQueue(_queueID);
    }
    
    /**
     * 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.cms.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---

    /**
     * Overridden for debugging purposes
     * to see when an instance of this class
     * is destroyed
     */
    protected void finalize() throws Throwable {
        _logger.write(this.toString(), Logger.DEBUG, "finalized by GC");
    }

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

    /**
     * Accessor to our Queue. The Control Handler needs to
     * get this reference to register us.
     *
     * @return a reference to our Queue
     */
    public Queue getQueue() {
        return _queue;
    }

//---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 Queue we'll use for buffering data to the client.
     */
    private Queue _queue;
    
    /**
     * The "servant" part of the client we're connected to.
     */
    private Client _client;
    
    /**
     * Our queue number within our Queue
     */
    private int _queueID;
    
    /**
     * The flag that dictates whether the main loop should *completely* exit
     */
    private boolean run;
    
    /**
     * A reference to our controlling class
     */
    private CorbaControlHandlerServant _cchServant;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.14
Committed:	Wed Feb 5 16:43:46 2003 UTC (21 years, 3 months ago) by tdb
Branch:	MAIN
Changes since 1.13:	+4 -4 lines
Log Message:	Changed the server to use the external util package. Quite a minor change, but does affect a lot of files.
#	Content
1	/*
2	* i-scream central monitoring system
3	* http://www.i-scream.org.uk
4	* Copyright (C) 2000-2002 i-scream
5	*
6	* This program is free software; you can redistribute it and/or
7	* modify it under the terms of the GNU General Public License
8	* as published by the Free Software Foundation; either version 2
9	* of the License, or (at your option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU General Public License
17	* along with this program; if not, write to the Free Software
18	* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19	*/
20
21	//---PACKAGE DECLARATION---
22	package uk.org.iscream.cms.server.clientinterface;
23
24	//---IMPORTS---
25	import uk.org.iscream.cms.util.*;
26	import uk.org.iscream.cms.server.componentmanager.*;
27	import uk.org.iscream.cms.server.core.*;
28	import uk.org.iscream.cms.server.client.*;
29
30
31	/**
32	* Acts as a Data Handler to a CORBA based client.
33	*
34	* @author $Author: tdb $
35	* @version $Id: CorbaDataHandler.java,v 1.13 2002/05/21 16:47:16 tdb Exp $
36	*/
37	class CorbaDataHandler extends Thread {
38
39	//---FINAL ATTRIBUTES---
40
41	/**
42	* The current CVS revision of this class
43	*/
44	public final String REVISION = "$Revision: 1.13 $";
45
46	//---STATIC METHODS---
47
48	//---CONSTRUCTORS---
49
50	/**
51	* Construct a new CorbaDataHandler.
52	*
53	* @param client A reference to the "servant" part of the connecting client.
54	* @param cchServer A reference to the class that is control us.
55	*/
56	public CorbaDataHandler(Client client, CorbaControlHandlerServant cchServant) {
57	// set the Thread name
58	setName("clientinterface.CorbaDataHandler");
59
60	ConfigurationProxy cp = ConfigurationProxy.getInstance();
61	String configName = "ClientInterface";
62	// see if this Queue needs a size limit
63	try {
64	int queueSizeLimit = Integer.parseInt(cp.getProperty(configName, "Queue.SizeLimit"));
65	String queueRemoveAlgorithm = cp.getProperty(configName, "Queue.RemoveAlgorithm");
66	int algorithm = StringUtils.getStringPos(queueRemoveAlgorithm, Queue.algorithms);
67	if(algorithm != -1) {
68	_logger.write(toString(), Logger.DEBUG, "Starting Queue with size limit of "+queueSizeLimit+", using remove algorithm "+queueRemoveAlgorithm);
69	// we have valid values, so lets start it.
70	_queue = new Queue(queueSizeLimit, algorithm);
71	}
72	else {
73	_logger.write(toString(), Logger.WARNING, "Bad Queue Algorithm configuration, not known: "+queueRemoveAlgorithm);
74	// just don't activate a limit
75	_queue = new Queue();
76	}
77
78	} catch (PropertyNotFoundException e) {
79	_logger.write(toString(), Logger.DEBUG, "Optional config not set: "+e);
80	// just don't activate a limit
81	_queue = new Queue();
82	} catch (NumberFormatException e) {
83	_logger.write(toString(), Logger.WARNING, "Bad Queue SizeLimit configuration: "+e);
84	// just don't activate a limit
85	_queue = new Queue();
86	}
87
88	_client = client;
89	_cchServant = cchServant;
90	_logger.write(toString(), Logger.SYSINIT, "created");
91	}
92
93	//---PUBLIC METHODS---
94
95	/**
96	* This method loops round until such a point as we shutdown. It keeps
97	* grabbing data items from it's Queue, then sends them on to the connected
98	* client over CORBA.
99	*/
100	public void run() {
101	// get a queue
102	_queueID = _queue.getQueue();
103	// we'll keep going until someone implements a "shutdown" :)
104	run = true;
105	// loop sending data
106	while(run) {
107	try {
108	String xml = (String) _queue.get(_queueID);
109	// if it's not null (which could happen if we're "released")
110	// send it on to the client that we're connected to.
111	if(xml != null) {
112	try {
113	_client.receiveXML(xml);
114	}
115	catch (org.omg.CORBA.COMM_FAILURE e) {
116	// lets stop sending, the client has quit
117	run = false;
118	_logger.write(toString(), Logger.ERROR, "Connection failure (COMM_FAILURE), client shutdown? : "+e);
119	}
120	catch (org.omg.CORBA.TRANSIENT e) {
121	// lets stop sending, the client has quit
122	run = false;
123	_logger.write(toString(), Logger.ERROR, "Connection failure (TRANSIENT), client shutdown? : "+e);
124	}
125	}
126	}
127	catch(InvalidQueueException e) {
128	// lets stop sending.
129	run = false;
130	_logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
131	}
132	}
133	// disconnect the servant above us, or at least try
134	_cchServant.disconnect();
135	// if we get here we've been told to stop
136	_logger.write(toString(), Logger.SYSMSG, "Shutting Down");
137	// remove ourselves from the queue
138	_queue.removeQueue(_queueID);
139	_queue.stopMonitor();
140	}
141
142	/**
143	* Method to shutdown this Data Handler. All this actually does
144	* is set a flag which the main loop will see and commence shutting
145	* down. This method will return before the main loop stops.
146	*/
147	public void shutdown() {
148	// set the main loop to stop
149	run=false;
150	// if the main loop is waiting for data it won't notice the
151	// above flag to stop. This bumps it out of the blocked get.
152	_queue.releaseQueue(_queueID);
153	}
154
155	/**
156	* Overrides the {@link java.lang.Object#toString() Object.toString()}
157	* method to provide clean logging (every class should have this).
158	*
159	* This uses the uk.org.iscream.cms.util.NameFormat class
160	* to format the toString()
161	*
162	* @return the name of this class and its CVS revision
163	*/
164	public String toString() {
165	return FormatName.getName(
166	_name,
167	getClass().getName(),
168	REVISION);
169	}
170
171	//---PRIVATE METHODS---
172
173	/**
174	* Overridden for debugging purposes
175	* to see when an instance of this class
176	* is destroyed
177	*/
178	protected void finalize() throws Throwable {
179	_logger.write(this.toString(), Logger.DEBUG, "finalized by GC");
180	}
181
182	//---ACCESSOR/MUTATOR METHODS---
183
184	/**
185	* Accessor to our Queue. The Control Handler needs to
186	* get this reference to register us.
187	*
188	* @return a reference to our Queue
189	*/
190	public Queue getQueue() {
191	return _queue;
192	}
193
194	//---ATTRIBUTES---
195
196	/**
197	* This is the friendly identifier of the
198	* component this class is running in.
199	* eg, a Filter may be called "filter1",
200	* If this class does not have an owning
201	* component, a name from the configuration
202	* can be placed here. This name could also
203	* be changed to null for utility classes.
204	*/
205	private String _name = ClientInterfaceMain.NAME;
206
207	/**
208	* This holds a reference to the
209	* system logger that is being used.
210	*/
211	private Logger _logger = ReferenceManager.getInstance().getLogger();
212
213	/**
214	* The Queue we'll use for buffering data to the client.
215	*/
216	private Queue _queue;
217
218	/**
219	* The "servant" part of the client we're connected to.
220	*/
221	private Client _client;
222
223	/**
224	* Our queue number within our Queue
225	*/
226	private int _queueID;
227
228	/**
229	* The flag that dictates whether the main loop should completely exit
230	*/
231	private boolean run;
232
233	/**
234	* A reference to our controlling class
235	*/
236	private CorbaControlHandlerServant _cchServant;
237
238	//---STATIC ATTRIBUTES---
239
240	}