server/clientinterface/CorbaDataHandler.java

/* 
 * i-scream central monitoring system
 * 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.server.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 1.11 2001/11/15 13:45:46 tdb Exp $
 */
class CorbaDataHandler extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.11 $";
    
//---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.server.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:	1.12
Committed:	Sat May 18 18:16:01 2002 UTC (22 years ago) by tdb
Branch:	MAIN
Changes since 1.11:	+22 -3 lines
Log Message:	i-scream is now licensed under the GPL. I've added the GPL headers to every source file, and put a full copy of the license in the appropriate places. I think I've covered everything. This is going to be a mad commit ;)
#	User	Rev	Content
1	tdb	1.12	/*
2			* i-scream central monitoring system
3			* Copyright (C) 2000-2002 i-scream
4			*
5			* This program is free software; you can redistribute it and/or
6			* modify it under the terms of the GNU General Public License
7			* as published by the Free Software Foundation; either version 2
8			* of the License, or (at your option) any later version.
9			*
10			* This program is distributed in the hope that it will be useful,
11			* but WITHOUT ANY WARRANTY; without even the implied warranty of
12			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13			* GNU General Public License for more details.
14			*
15			* You should have received a copy of the GNU General Public License
16			* along with this program; if not, write to the Free Software
17			* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
18			*/
19
20	tdb	1.1	//---PACKAGE DECLARATION---
21	tdb	1.10	package uk.org.iscream.cms.server.clientinterface;
22	tdb	1.1
23			//---IMPORTS---
24	tdb	1.10	import uk.org.iscream.cms.server.util.*;
25			import uk.org.iscream.cms.server.componentmanager.*;
26			import uk.org.iscream.cms.server.core.*;
27			import uk.org.iscream.cms.server.client.*;
28	tdb	1.1
29
30			/**
31			* Acts as a Data Handler to a CORBA based client.
32			*
33	tdb	1.12	* @author $Author: tdb $
34			* @version $Id: CorbaDataHandler.java,v 1.11 2001/11/15 13:45:46 tdb Exp $
35	tdb	1.1	*/
36			class CorbaDataHandler extends Thread {
37
38			//---FINAL ATTRIBUTES---
39
40			/**
41			* The current CVS revision of this class
42			*/
43	tdb	1.12	public final String REVISION = "$Revision: 1.11 $";
44	tdb	1.1
45			//---STATIC METHODS---
46
47			//---CONSTRUCTORS---
48
49			/**
50			* Construct a new CorbaDataHandler.
51			*
52			* @param client A reference to the "servant" part of the connecting client.
53	tdb	1.7	* @param cchServer A reference to the class that is control us.
54	tdb	1.1	*/
55	tdb	1.7	public CorbaDataHandler(Client client, CorbaControlHandlerServant cchServant) {
56	tdb	1.5	// set the Thread name
57			setName("clientinterface.CorbaDataHandler");
58
59	tdb	1.9	ConfigurationProxy cp = ConfigurationProxy.getInstance();
60			String configName = "ClientInterface";
61			// see if this Queue needs a size limit
62			try {
63			int queueSizeLimit = Integer.parseInt(cp.getProperty(configName, "Queue.SizeLimit"));
64			String queueRemoveAlgorithm = cp.getProperty(configName, "Queue.RemoveAlgorithm");
65			int algorithm = StringUtils.getStringPos(queueRemoveAlgorithm, Queue.algorithms);
66			if(algorithm != -1) {
67			_logger.write(toString(), Logger.DEBUG, "Starting Queue with size limit of "+queueSizeLimit+", using remove algorithm "+queueRemoveAlgorithm);
68			// we have valid values, so lets start it.
69			_queue = new Queue(queueSizeLimit, algorithm);
70			}
71			else {
72			_logger.write(toString(), Logger.WARNING, "Bad Queue Algorithm configuration, not known: "+queueRemoveAlgorithm);
73			// just don't activate a limit
74			_queue = new Queue();
75			}
76
77			} catch (PropertyNotFoundException e) {
78			_logger.write(toString(), Logger.DEBUG, "Optional config not set: "+e);
79			// just don't activate a limit
80			_queue = new Queue();
81			} catch (NumberFormatException e) {
82			_logger.write(toString(), Logger.WARNING, "Bad Queue SizeLimit configuration: "+e);
83			// just don't activate a limit
84			_queue = new Queue();
85			}
86
87	tdb	1.1	_client = client;
88	tdb	1.7	_cchServant = cchServant;
89	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "created");
90			}
91
92			//---PUBLIC METHODS---
93
94			/**
95			* This method loops round until such a point as we shutdown. It keeps
96			* grabbing data items from it's Queue, then sends them on to the connected
97			* client over CORBA.
98			*/
99			public void run() {
100			// get a queue
101			_queueID = _queue.getQueue();
102			// we'll keep going until someone implements a "shutdown" :)
103			run = true;
104			// loop sending data
105			while(run) {
106			try {
107			String xml = (String) _queue.get(_queueID);
108			// if it's not null (which could happen if we're "released")
109			// send it on to the client that we're connected to.
110			if(xml != null) {
111	tdb	1.3	try {
112			_client.receiveXML(xml);
113			}
114			catch (org.omg.CORBA.COMM_FAILURE e) {
115			// lets stop sending, the client has quit
116			run = false;
117	tdb	1.11	_logger.write(toString(), Logger.ERROR, "Connection failure (COMM_FAILURE), client shutdown? : "+e);
118			}
119			catch (org.omg.CORBA.TRANSIENT e) {
120			// lets stop sending, the client has quit
121			run = false;
122			_logger.write(toString(), Logger.ERROR, "Connection failure (TRANSIENT), client shutdown? : "+e);
123	tdb	1.3	}
124	tdb	1.1	}
125			}
126			catch(InvalidQueueException e) {
127			// lets stop sending.
128			run = false;
129			_logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
130			}
131			}
132	tdb	1.11	// disconnect the servant above us, or at least try
133			_cchServant.disconnect();
134	tdb	1.1	// if we get here we've been told to stop
135			_logger.write(toString(), Logger.SYSMSG, "Shutting Down");
136			// remove ourselves from the queue
137			_queue.removeQueue(_queueID);
138	tdb	1.4	_queue.stopMonitor();
139	tdb	1.1	}
140
141			/**
142			* Method to shutdown this Data Handler. All this actually does
143			* is set a flag which the main loop will see and commence shutting
144			* down. This method will return before the main loop stops.
145			*/
146			public void shutdown() {
147			// set the main loop to stop
148			run=false;
149			// if the main loop is waiting for data it won't notice the
150			// above flag to stop. This bumps it out of the blocked get.
151			_queue.releaseQueue(_queueID);
152			}
153
154			/**
155			* Overrides the {@link java.lang.Object#toString() Object.toString()}
156			* method to provide clean logging (every class should have this).
157			*
158	tdb	1.10	* This uses the uk.org.iscream.cms.server.util.NameFormat class
159	tdb	1.1	* to format the toString()
160			*
161			* @return the name of this class and its CVS revision
162			*/
163			public String toString() {
164			return FormatName.getName(
165			_name,
166			getClass().getName(),
167			REVISION);
168			}
169
170			//---PRIVATE METHODS---
171	tdb	1.8
172			/**
173			* Overridden for debugging purposes
174			* to see when an instance of this class
175			* is destroyed
176			*/
177			protected void finalize() throws Throwable {
178			_logger.write(this.toString(), Logger.DEBUG, "finalized by GC");
179			}
180	tdb	1.1
181			//---ACCESSOR/MUTATOR METHODS---
182
183			/**
184			* Accessor to our Queue. The Control Handler needs to
185			* get this reference to register us.
186			*
187			* @return a reference to our Queue
188			*/
189			public Queue getQueue() {
190			return _queue;
191			}
192
193			//---ATTRIBUTES---
194
195			/**
196			* This is the friendly identifier of the
197			* component this class is running in.
198			* eg, a Filter may be called "filter1",
199			* If this class does not have an owning
200			* component, a name from the configuration
201			* can be placed here. This name could also
202			* be changed to null for utility classes.
203			*/
204			private String _name = ClientInterfaceMain.NAME;
205
206			/**
207			* This holds a reference to the
208			* system logger that is being used.
209			*/
210			private Logger _logger = ReferenceManager.getInstance().getLogger();
211
212			/**
213			* The Queue we'll use for buffering data to the client.
214			*/
215			private Queue _queue;
216
217			/**
218			* The "servant" part of the client we're connected to.
219			*/
220			private Client _client;
221
222			/**
223			* Our queue number within our Queue
224			*/
225			private int _queueID;
226
227			/**
228			* The flag that dictates whether the main loop should completely exit
229			*/
230			private boolean run;
231	tdb	1.7
232			/**
233			* A reference to our controlling class
234			*/
235			private CorbaControlHandlerServant _cchServant;
236	tdb	1.1
237			//---STATIC ATTRIBUTES---
238
239			}