server/clientinterface/CorbaControlHandlerServant.java

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

//---IMPORTS---
import uk.ac.ukc.iscream.util.*;
import uk.ac.ukc.iscream.componentmanager.*;
import uk.ac.ukc.iscream.core.*;
import uk.ac.ukc.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 1.3 2001/02/05 00:58:46 tdb1 Exp $
 */
class CorbaControlHandlerServant extends CorbaControlHandlerPOA {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.3 $";
    
//---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.
     */
    public CorbaControlHandlerServant(PacketSorter packetSorter, Client client) {
        _packetSorter = packetSorter;
        _hostList = "";
        _client = client;
        _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);
            // startup a monitor on the DataHandler's queue, every minute
            dh.getQueue().startMonitor(60*1000, _packetSorter.getQueue(), _name);
            // 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;
        }
    }
    
    /**
     * Overrides the {@link java.lang.Object#toString() Object.toString()}
     * method to provide clean logging (every class should have this).
     *
     * This uses the uk.ac.ukc.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 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;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.4
Committed:	Mon Feb 12 02:23:52 2001 UTC (23 years, 3 months ago) by tdb
Branch:	MAIN
Changes since 1.3:	+5 -3 lines
Log Message:	Now monitor the Queue here every 60 seconds, reporting back to the Queue in the PacketSorter class.
#	User	Rev	Content
1	tdb	1.1	//---PACKAGE DECLARATION---
2			package uk.ac.ukc.iscream.clientinterface;
3
4			//---IMPORTS---
5			import uk.ac.ukc.iscream.util.*;
6			import uk.ac.ukc.iscream.componentmanager.*;
7			import uk.ac.ukc.iscream.core.*;
8			import uk.ac.ukc.iscream.client.*;
9
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			* @version $Id: CorbaControlHandlerServant.java,v 1.3 2001/02/05 00:58:46 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	1.4	public final String REVISION = "$Revision: 1.3 $";
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			*/
39	tdb	1.3	public CorbaControlHandlerServant(PacketSorter packetSorter, Client client) {
40	tdb	1.1	_packetSorter = packetSorter;
41			_hostList = "";
42			_client = client;
43	tdb	1.3	_dataHandler = null;
44	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "created");
45			}
46
47			//---PUBLIC METHODS---
48
49			/**
50			* Start sending data to the client.
51			*
52			* @return a boolean stating whether the attempt to start succeeded
53			*/
54			public boolean startData() {
55	tdb	1.3	if(_dataHandler == null) {
56			// create a new DataHandler
57			CorbaDataHandler dh = new CorbaDataHandler(_client);
58	tdb	1.1	// register the Queue
59	tdb	1.3	_packetSorter.register(dh.getQueue(), _hostList);
60	tdb	1.4	// startup a monitor on the DataHandler's queue, every minute
61			dh.getQueue().startMonitor(60*1000, _packetSorter.getQueue(), _name);
62	tdb	1.3	// start the DataHandler running
63			dh.start();
64			// keep a reference
65			_dataHandler = dh;
66	tdb	1.1	return true;
67			}
68			else {
69			return false;
70			}
71			}
72
73			/**
74			* Stop sending data to the client.
75			*
76			* @return a boolean stating whether the attempt to stop succeeded
77			*/
78			public boolean stopData() {
79	tdb	1.3	if(_dataHandler != null) {
80	tdb	1.1	// deregister the Queue
81	tdb	1.3	_packetSorter.deregister(_dataHandler.getQueue(), _hostList);
82			// stop the DataHandler
83			_dataHandler.shutdown();
84			// destroy the reference
85			_dataHandler = null;
86	tdb	1.1	return true;
87			}
88			else {
89			return false;
90			}
91			}
92
93			/**
94			* Sets the host list for the Client to the requested semi-colon separated
95			* list of hostnames. This will only succeed if we are not sending data.
96			*
97			* @param hostList A semi-colon separated list of hostnames to use.
98			* @return Whether the request succeeded.
99			*/
100			public boolean setHostList(String hostList) {
101	tdb	1.3	if(_dataHandler == null) {
102	tdb	1.1	_hostList = hostList;
103			return true;
104			}
105			else {
106			return false;
107			}
108			}
109
110			/**
111			* Overrides the {@link java.lang.Object#toString() Object.toString()}
112			* method to provide clean logging (every class should have this).
113			*
114			* This uses the uk.ac.ukc.iscream.util.NameFormat class
115			* to format the toString()
116			*
117			* @return the name of this class and its CVS revision
118			*/
119			public String toString() {
120			return FormatName.getName(
121			_name,
122			getClass().getName(),
123			REVISION);
124			}
125
126			//---PRIVATE METHODS---
127
128			//---ACCESSOR/MUTATOR METHODS---
129
130			//---ATTRIBUTES---
131
132			/**
133			* This is the friendly identifier of the
134			* component this class is running in.
135			* eg, a Filter may be called "filter1",
136			* If this class does not have an owning
137			* component, a name from the configuration
138			* can be placed here. This name could also
139			* be changed to null for utility classes.
140			*/
141			private String _name = ClientInterfaceMain.NAME;
142
143			/**
144			* This holds a reference to the
145			* system logger that is being used.
146			*/
147			private Logger _logger = ReferenceManager.getInstance().getLogger();
148
149			/**
150			* A reference to the PacketSorter.
151			*/
152			private PacketSorter _packetSorter;
153
154			/**
155			* The host list the Client has requested
156			*/
157			private String _hostList;
158
159			/**
160			* The "servant" part of the client we're connected to.
161			*/
162			private Client _client;
163
164			/**
165	tdb	1.3	* A reference to our DataHandler, if we have one
166	tdb	1.1	*/
167	tdb	1.3	private CorbaDataHandler _dataHandler;
168	tdb	1.1
169			//---STATIC ATTRIBUTES---
170
171			}