server/clientinterface/CorbaControlHandlerServant.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 uk.org.iscream.client.*;


/**
 * Acts as a Control Handler to a CORBA based client.
 *
 * !!! FUNDAMENTAL DESIGN PROBLEM !!!
 * !!! Need a way to "shutdown" this class !!!
 *
 * @author  $Author: tdb1 $
 * @version $Id: CorbaControlHandlerServant.java,v 1.9 2001/03/13 20:55:59 tdb1 Exp $
 */
class CorbaControlHandlerServant extends CorbaControlHandlerPOA {

//---FINAL ATTRIBUTES---

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

//---CONSTRUCTORS---
    
    /**
     * Construct a new CorbaControlHandlerServant.
     *
     * @param packetSorter A reference to the PacketSorter in the component
     * @param client A reference to the "servant" part of the connecting client.
     * @param queueMonitorInterval The interval at which to monitor our Queue.
     * @param clientname A name to identify the client.
     */
    public CorbaControlHandlerServant(PacketSorter packetSorter, Client client, String clientname) {
        _packetSorter = packetSorter;
        _hostList = "";
        _client = client;
        _clientname = clientname;
        _dataHandler = null;
        _logger.write(toString(), Logger.SYSINIT, "created");
    }
    
//---PUBLIC METHODS---
    
    /**
     * Start sending data to the client.
     *
     * @return a boolean stating whether the attempt to start succeeded
     */
    public boolean startData() {
        if(_dataHandler == null) {
            // create a new DataHandler
            CorbaDataHandler dh = new CorbaDataHandler(_client);
            // register the Queue
            _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 + " CorbaHandler:"+_clientname;
                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 the DataHandler running
            dh.start();
            // keep a reference
            _dataHandler = dh;
            return true;
        }
        else {
            return false;
        }
    }
    
    /**
     * Stop sending data to the client.
     *
     * @return a boolean stating whether the attempt to stop succeeded
     */
    public boolean stopData() {
        if(_dataHandler != null) {
            // deregister the Queue
            _packetSorter.deregister(_dataHandler.getQueue(), _hostList);
            // stop the DataHandler
            _dataHandler.shutdown();
            // destroy the reference
            _dataHandler = null;
            return true;
        }
        else {
            return false;
        }
    }
    
    /**
     * Sets the host list for the Client to the requested semi-colon separated
     * list of hostnames. This will only succeed if we are not sending data.
     *
     * @param hostList A semi-colon separated list of hostnames to use.
     * @return Whether the request succeeded.
     */
    public boolean setHostList(String hostList) {
        if(_dataHandler == null) {
            _hostList = hostList;
            return true;
        }
        else {
            return false;
        }
    }
    
    /**
     * Disconnect, this will shutdown the data and unhook from
     * the CORBA ORB.
     */
    public void disconnect() {
        // close the data handler
        stopData();
        // disconnect from the ORB
        try {
            byte[] oid = _refman.getRootPOA().servant_to_id(this);
            _refman.getRootPOA().deactivate_object(oid);
        } catch(Exception e) {
            _logger.write(this.toString(), Logger.ERROR, "disconnect failed: "+e);
        }
    }
    
    /**
     * 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---

//---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 reference manager in use
     */
    private ReferenceManager _refman = ReferenceManager.getInstance();
    
    /**
         * A reference to the PacketSorter.
         */
    private PacketSorter _packetSorter;
    
    /**
     * The host list the Client has requested
     */
    private String _hostList;
    
    /**
     * The "servant" part of the client we're connected to.
     */
    private Client _client;
    
    /**
     * A reference to our DataHandler, if we have one
     */
    private CorbaDataHandler _dataHandler;
    
    /**
     * A name to identify the client
     */
    private String _clientname;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.10
Committed:	Wed Mar 14 23:25:29 2001 UTC (23 years, 2 months ago) by tdb
Branch:	MAIN
Changes since 1.9:	+8 -8 lines
Log Message:	The whole server package structure has been changed. Old Package: uk.ac.ukc.iscream.* New Package: uk.org.iscream.*
#	User	Rev	Content
1	tdb	1.1	//---PACKAGE DECLARATION---
2	tdb	1.10	package uk.org.iscream.clientinterface;
3	tdb	1.1
4			//---IMPORTS---
5	tdb	1.10	import uk.org.iscream.util.*;
6			import uk.org.iscream.componentmanager.*;
7			import uk.org.iscream.core.*;
8			import uk.org.iscream.client.*;
9	tdb	1.1
10
11			/**
12	tdb	1.3	* Acts as a Control Handler to a CORBA based client.
13	tdb	1.1	*
14			* !!! FUNDAMENTAL DESIGN PROBLEM !!!
15			* !!! Need a way to "shutdown" this class !!!
16			*
17	tdb	1.4	* @author $Author: tdb1 $
18	tdb	1.10	* @version $Id: CorbaControlHandlerServant.java,v 1.9 2001/03/13 20:55:59 tdb1 Exp $
19	tdb	1.1	*/
20	tdb	1.3	class CorbaControlHandlerServant extends CorbaControlHandlerPOA {
21	tdb	1.1
22			//---FINAL ATTRIBUTES---
23
24			/**
25			* The current CVS revision of this class
26			*/
27	tdb	1.10	public final String REVISION = "$Revision: 1.9 $";
28	tdb	1.1
29			//---STATIC METHODS---
30
31			//---CONSTRUCTORS---
32
33			/**
34	tdb	1.3	* Construct a new CorbaControlHandlerServant.
35	tdb	1.1	*
36			* @param packetSorter A reference to the PacketSorter in the component
37			* @param client A reference to the "servant" part of the connecting client.
38	tdb	1.5	* @param queueMonitorInterval The interval at which to monitor our Queue.
39	tdb	1.6	* @param clientname A name to identify the client.
40	tdb	1.1	*/
41	tdb	1.7	public CorbaControlHandlerServant(PacketSorter packetSorter, Client client, String clientname) {
42	tdb	1.1	_packetSorter = packetSorter;
43			_hostList = "";
44			_client = client;
45	tdb	1.6	_clientname = clientname;
46	tdb	1.3	_dataHandler = null;
47	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "created");
48			}
49
50			//---PUBLIC METHODS---
51
52			/**
53			* Start sending data to the client.
54			*
55			* @return a boolean stating whether the attempt to start succeeded
56			*/
57			public boolean startData() {
58	tdb	1.3	if(_dataHandler == null) {
59			// create a new DataHandler
60			CorbaDataHandler dh = new CorbaDataHandler(_client);
61	tdb	1.1	// register the Queue
62	tdb	1.3	_packetSorter.register(dh.getQueue(), _hostList);
63	tdb	1.7	try {
64			// startup a monitor on the DataHandler's queue
65			ConfigurationProxy cp = ConfigurationProxy.getInstance();
66			int queueMonitorInterval = Integer.parseInt(cp.getProperty("ClientInterface", "Queue.MonitorInterval"));
67			String queueName = _name + " CorbaHandler:"+_clientname;
68			dh.getQueue().startMonitor(queueMonitorInterval*1000, _packetSorter.getQueue(), queueName);
69			} catch (PropertyNotFoundException e) {
70			_logger.write(toString(), Logger.WARNING, "failed to find queue monitor config, disabling. " + e);
71			}
72	tdb	1.3	// start the DataHandler running
73			dh.start();
74			// keep a reference
75			_dataHandler = dh;
76	tdb	1.1	return true;
77			}
78			else {
79			return false;
80			}
81			}
82
83			/**
84			* Stop sending data to the client.
85			*
86			* @return a boolean stating whether the attempt to stop succeeded
87			*/
88			public boolean stopData() {
89	tdb	1.3	if(_dataHandler != null) {
90	tdb	1.1	// deregister the Queue
91	tdb	1.3	_packetSorter.deregister(_dataHandler.getQueue(), _hostList);
92			// stop the DataHandler
93			_dataHandler.shutdown();
94			// destroy the reference
95			_dataHandler = null;
96	tdb	1.1	return true;
97			}
98			else {
99			return false;
100			}
101			}
102
103			/**
104			* Sets the host list for the Client to the requested semi-colon separated
105			* list of hostnames. This will only succeed if we are not sending data.
106			*
107			* @param hostList A semi-colon separated list of hostnames to use.
108			* @return Whether the request succeeded.
109			*/
110			public boolean setHostList(String hostList) {
111	tdb	1.3	if(_dataHandler == null) {
112	tdb	1.1	_hostList = hostList;
113			return true;
114			}
115			else {
116			return false;
117			}
118			}
119
120			/**
121	tdb	1.8	* Disconnect, this will shutdown the data and unhook from
122			* the CORBA ORB.
123			*/
124			public void disconnect() {
125			// close the data handler
126			stopData();
127			// disconnect from the ORB
128			try {
129	tdb	1.9	byte[] oid = _refman.getRootPOA().servant_to_id(this);
130			_refman.getRootPOA().deactivate_object(oid);
131	tdb	1.8	} catch(Exception e) {
132			_logger.write(this.toString(), Logger.ERROR, "disconnect failed: "+e);
133			}
134			}
135
136			/**
137	tdb	1.1	* Overrides the {@link java.lang.Object#toString() Object.toString()}
138			* method to provide clean logging (every class should have this).
139			*
140	tdb	1.10	* This uses the uk.org.iscream.util.NameFormat class
141	tdb	1.1	* to format the toString()
142			*
143			* @return the name of this class and its CVS revision
144			*/
145			public String toString() {
146			return FormatName.getName(
147			_name,
148			getClass().getName(),
149			REVISION);
150			}
151
152			//---PRIVATE METHODS---
153
154			//---ACCESSOR/MUTATOR METHODS---
155
156			//---ATTRIBUTES---
157
158			/**
159			* This is the friendly identifier of the
160			* component this class is running in.
161			* eg, a Filter may be called "filter1",
162			* If this class does not have an owning
163			* component, a name from the configuration
164			* can be placed here. This name could also
165			* be changed to null for utility classes.
166			*/
167			private String _name = ClientInterfaceMain.NAME;
168
169			/**
170			* This holds a reference to the
171			* system logger that is being used.
172			*/
173			private Logger _logger = ReferenceManager.getInstance().getLogger();
174	tdb	1.8
175			/**
176			* A reference to the reference manager in use
177			*/
178			private ReferenceManager _refman = ReferenceManager.getInstance();
179	tdb	1.1
180			/**
181			* A reference to the PacketSorter.
182			*/
183			private PacketSorter _packetSorter;
184
185			/**
186			* The host list the Client has requested
187			*/
188			private String _hostList;
189
190			/**
191			* The "servant" part of the client we're connected to.
192			*/
193			private Client _client;
194
195			/**
196	tdb	1.3	* A reference to our DataHandler, if we have one
197	tdb	1.1	*/
198	tdb	1.3	private CorbaDataHandler _dataHandler;
199	tdb	1.6
200			/**
201			* A name to identify the client
202			*/
203			private String _clientname;
204	tdb	1.1
205			//---STATIC ATTRIBUTES---
206
207			}