server/clientinterface/CorbaDataHandler.java

//---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: tdb1 $
 * @version $Id: CorbaDataHandler.java,v 1.9 2001/03/16 16:11:31 tdb1 Exp $
 */
class CorbaDataHandler extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.9 $";
    
//---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, client shutdown? : "+e);
                        // disconnect the servant above us, or at least try
                        _cchServant.disconnect();
                    }
                }
            }
            catch(InvalidQueueException e) {
                // lets stop sending.
                run = false;
                _logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
            }
        }
        // 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:	1.10
Committed:	Tue May 29 17:02:34 2001 UTC (22 years, 11 months ago) by tdb
Branch:	MAIN
Changes since 1.9:	+8 -8 lines
Log Message:	Major change in the java package naming. This has been held off for some time now, but it really needed doing. The future packaging of all i-scream products will be; uk.org.iscream.<product>.<subpart>.* In the case of the central monitoring system server this will be; uk.org.iscream.cms.server.* The whole server has been changed to follow this structure, and tested to a smallish extent. Further changes in other parts of the CMS will follow.
#	User	Rev	Content
1	tdb	1.1	//---PACKAGE DECLARATION---
2	tdb	1.10	package uk.org.iscream.cms.server.clientinterface;
3	tdb	1.1
4			//---IMPORTS---
5	tdb	1.10	import uk.org.iscream.cms.server.util.*;
6			import uk.org.iscream.cms.server.componentmanager.*;
7			import uk.org.iscream.cms.server.core.*;
8			import uk.org.iscream.cms.server.client.*;
9	tdb	1.1
10
11			/**
12			* Acts as a Data Handler to a CORBA based client.
13			*
14	tdb	1.2	* @author $Author: tdb1 $
15	tdb	1.10	* @version $Id: CorbaDataHandler.java,v 1.9 2001/03/16 16:11:31 tdb1 Exp $
16	tdb	1.1	*/
17			class CorbaDataHandler extends Thread {
18
19			//---FINAL ATTRIBUTES---
20
21			/**
22			* The current CVS revision of this class
23			*/
24	tdb	1.10	public final String REVISION = "$Revision: 1.9 $";
25	tdb	1.1
26			//---STATIC METHODS---
27
28			//---CONSTRUCTORS---
29
30			/**
31			* Construct a new CorbaDataHandler.
32			*
33			* @param client A reference to the "servant" part of the connecting client.
34	tdb	1.7	* @param cchServer A reference to the class that is control us.
35	tdb	1.1	*/
36	tdb	1.7	public CorbaDataHandler(Client client, CorbaControlHandlerServant cchServant) {
37	tdb	1.5	// set the Thread name
38			setName("clientinterface.CorbaDataHandler");
39
40	tdb	1.9	ConfigurationProxy cp = ConfigurationProxy.getInstance();
41			String configName = "ClientInterface";
42			// see if this Queue needs a size limit
43			try {
44			int queueSizeLimit = Integer.parseInt(cp.getProperty(configName, "Queue.SizeLimit"));
45			String queueRemoveAlgorithm = cp.getProperty(configName, "Queue.RemoveAlgorithm");
46			int algorithm = StringUtils.getStringPos(queueRemoveAlgorithm, Queue.algorithms);
47			if(algorithm != -1) {
48			_logger.write(toString(), Logger.DEBUG, "Starting Queue with size limit of "+queueSizeLimit+", using remove algorithm "+queueRemoveAlgorithm);
49			// we have valid values, so lets start it.
50			_queue = new Queue(queueSizeLimit, algorithm);
51			}
52			else {
53			_logger.write(toString(), Logger.WARNING, "Bad Queue Algorithm configuration, not known: "+queueRemoveAlgorithm);
54			// just don't activate a limit
55			_queue = new Queue();
56			}
57
58			} catch (PropertyNotFoundException e) {
59			_logger.write(toString(), Logger.DEBUG, "Optional config not set: "+e);
60			// just don't activate a limit
61			_queue = new Queue();
62			} catch (NumberFormatException e) {
63			_logger.write(toString(), Logger.WARNING, "Bad Queue SizeLimit configuration: "+e);
64			// just don't activate a limit
65			_queue = new Queue();
66			}
67
68	tdb	1.1	_client = client;
69	tdb	1.7	_cchServant = cchServant;
70	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "created");
71			}
72
73			//---PUBLIC METHODS---
74
75			/**
76			* This method loops round until such a point as we shutdown. It keeps
77			* grabbing data items from it's Queue, then sends them on to the connected
78			* client over CORBA.
79			*/
80			public void run() {
81			// get a queue
82			_queueID = _queue.getQueue();
83			// we'll keep going until someone implements a "shutdown" :)
84			run = true;
85			// loop sending data
86			while(run) {
87			try {
88			String xml = (String) _queue.get(_queueID);
89			// if it's not null (which could happen if we're "released")
90			// send it on to the client that we're connected to.
91			if(xml != null) {
92	tdb	1.3	try {
93			_client.receiveXML(xml);
94			}
95			catch (org.omg.CORBA.COMM_FAILURE e) {
96			// lets stop sending, the client has quit
97			run = false;
98			_logger.write(toString(), Logger.ERROR, "Connection failure, client shutdown? : "+e);
99	tdb	1.7	// disconnect the servant above us, or at least try
100			_cchServant.disconnect();
101	tdb	1.3	}
102	tdb	1.1	}
103			}
104			catch(InvalidQueueException e) {
105			// lets stop sending.
106			run = false;
107			_logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
108			}
109			}
110			// if we get here we've been told to stop
111			_logger.write(toString(), Logger.SYSMSG, "Shutting Down");
112			// remove ourselves from the queue
113			_queue.removeQueue(_queueID);
114	tdb	1.4	_queue.stopMonitor();
115	tdb	1.1	}
116
117			/**
118			* Method to shutdown this Data Handler. All this actually does
119			* is set a flag which the main loop will see and commence shutting
120			* down. This method will return before the main loop stops.
121			*/
122			public void shutdown() {
123			// set the main loop to stop
124			run=false;
125			// if the main loop is waiting for data it won't notice the
126			// above flag to stop. This bumps it out of the blocked get.
127			_queue.releaseQueue(_queueID);
128			}
129
130			/**
131			* Overrides the {@link java.lang.Object#toString() Object.toString()}
132			* method to provide clean logging (every class should have this).
133			*
134	tdb	1.10	* This uses the uk.org.iscream.cms.server.util.NameFormat class
135	tdb	1.1	* to format the toString()
136			*
137			* @return the name of this class and its CVS revision
138			*/
139			public String toString() {
140			return FormatName.getName(
141			_name,
142			getClass().getName(),
143			REVISION);
144			}
145
146			//---PRIVATE METHODS---
147	tdb	1.8
148			/**
149			* Overridden for debugging purposes
150			* to see when an instance of this class
151			* is destroyed
152			*/
153			protected void finalize() throws Throwable {
154			_logger.write(this.toString(), Logger.DEBUG, "finalized by GC");
155			}
156	tdb	1.1
157			//---ACCESSOR/MUTATOR METHODS---
158
159			/**
160			* Accessor to our Queue. The Control Handler needs to
161			* get this reference to register us.
162			*
163			* @return a reference to our Queue
164			*/
165			public Queue getQueue() {
166			return _queue;
167			}
168
169			//---ATTRIBUTES---
170
171			/**
172			* This is the friendly identifier of the
173			* component this class is running in.
174			* eg, a Filter may be called "filter1",
175			* If this class does not have an owning
176			* component, a name from the configuration
177			* can be placed here. This name could also
178			* be changed to null for utility classes.
179			*/
180			private String _name = ClientInterfaceMain.NAME;
181
182			/**
183			* This holds a reference to the
184			* system logger that is being used.
185			*/
186			private Logger _logger = ReferenceManager.getInstance().getLogger();
187
188			/**
189			* The Queue we'll use for buffering data to the client.
190			*/
191			private Queue _queue;
192
193			/**
194			* The "servant" part of the client we're connected to.
195			*/
196			private Client _client;
197
198			/**
199			* Our queue number within our Queue
200			*/
201			private int _queueID;
202
203			/**
204			* The flag that dictates whether the main loop should completely exit
205			*/
206			private boolean run;
207	tdb	1.7
208			/**
209			* A reference to our controlling class
210			*/
211			private CorbaControlHandlerServant _cchServant;
212	tdb	1.1
213			//---STATIC ATTRIBUTES---
214
215			}