server/clientinterface/CorbaControlHandlerServant.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.*;


/**
 * Acts as a Control Handler to a CORBA based client.
 *
 * @author  $Author: tdb $
 * @version $Id: CorbaControlHandlerServant.java,v 1.17 2003/02/05 16:43:46 tdb Exp $
 */
class CorbaControlHandlerServant extends CorbaControlHandlerPOA {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.17 $";
    
//---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 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, this);
            // 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.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---

//---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:	1.18
Committed:	Mon May 5 22:05:06 2003 UTC (21 years ago) by tdb
Branch:	MAIN
Changes since 1.17:	+2 -4 lines
Log Message:	Tidy up of the client interface code - more commonly known as the "right hand side of the server". Right since the start the filter side of the server has been nice and tree like - every Filter sent data to another Filter. At the top of the tree there was a "special" Filter known as the RootFilter, which to the other Filters just looked like a normal Filter. This was nice, and simple, and expandable. The Client Interface on the other hand was messy. The root filter had some hacky wrapper threads which pulled from a queue and pushed to the relevant client interfaces (one for real time stuff, and the other for databases). There was no simple room for expandability - it was all hardwired to do just what was needed at the time. This commit changes that. A Client Interface now connects to another Client Interface, with a special one being found in the RootFilter (yes, maybe that needs a name change now :-). So we can chain client interfaces, and move other bits and bobs around in the server - for example, alerting no longer needs to be connected to the Client Interface, it can connect straight to the RootFilter (or, wherever the config tells it ;). Hopefully this sanitizes the underlying layout of the server a bit. As a final note, I dropped the DBInterface. This used to insert data in to a MySQL database. We've long since stopped using that, and it's fallen behind and is way out of date. For now, it's gone in to the attic.
#	User	Rev	Content
1	tdb	1.15	/*
2			* i-scream central monitoring system
3	tdb	1.16	* http://www.i-scream.org.uk
4	tdb	1.15	* 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	tdb	1.1	//---PACKAGE DECLARATION---
22	tdb	1.14	package uk.org.iscream.cms.server.clientinterface;
23	tdb	1.1
24			//---IMPORTS---
25	tdb	1.17	import uk.org.iscream.cms.util.*;
26	tdb	1.14	import uk.org.iscream.cms.server.componentmanager.*;
27			import uk.org.iscream.cms.server.core.*;
28	tdb	1.1
29
30			/**
31	tdb	1.3	* Acts as a Control Handler to a CORBA based client.
32	tdb	1.1	*
33	tdb	1.15	* @author $Author: tdb $
34	tdb	1.18	* @version $Id: CorbaControlHandlerServant.java,v 1.17 2003/02/05 16:43:46 tdb Exp $
35	tdb	1.1	*/
36	tdb	1.3	class CorbaControlHandlerServant extends CorbaControlHandlerPOA {
37	tdb	1.1
38			//---FINAL ATTRIBUTES---
39
40			/**
41			* The current CVS revision of this class
42			*/
43	tdb	1.18	public final String REVISION = "$Revision: 1.17 $";
44	tdb	1.1
45			//---STATIC METHODS---
46
47			//---CONSTRUCTORS---
48
49			/**
50	tdb	1.3	* Construct a new CorbaControlHandlerServant.
51	tdb	1.1	*
52			* @param packetSorter A reference to the PacketSorter in the component
53			* @param client A reference to the "servant" part of the connecting client.
54	tdb	1.6	* @param clientname A name to identify the client.
55	tdb	1.1	*/
56	tdb	1.7	public CorbaControlHandlerServant(PacketSorter packetSorter, Client client, String clientname) {
57	tdb	1.1	_packetSorter = packetSorter;
58			_hostList = "";
59			_client = client;
60	tdb	1.6	_clientname = clientname;
61	tdb	1.3	_dataHandler = null;
62	tdb	1.1	_logger.write(toString(), Logger.SYSINIT, "created");
63			}
64
65			//---PUBLIC METHODS---
66
67			/**
68			* Start sending data to the client.
69			*
70			* @return a boolean stating whether the attempt to start succeeded
71			*/
72			public boolean startData() {
73	tdb	1.3	if(_dataHandler == null) {
74			// create a new DataHandler
75	tdb	1.11	CorbaDataHandler dh = new CorbaDataHandler(_client, this);
76	tdb	1.1	// register the Queue
77	tdb	1.3	_packetSorter.register(dh.getQueue(), _hostList);
78	tdb	1.7	try {
79			// startup a monitor on the DataHandler's queue
80			ConfigurationProxy cp = ConfigurationProxy.getInstance();
81			int queueMonitorInterval = Integer.parseInt(cp.getProperty("ClientInterface", "Queue.MonitorInterval"));
82			String queueName = _name + " CorbaHandler:"+_clientname;
83			dh.getQueue().startMonitor(queueMonitorInterval*1000, _packetSorter.getQueue(), queueName);
84			} catch (PropertyNotFoundException e) {
85			_logger.write(toString(), Logger.WARNING, "failed to find queue monitor config, disabling. " + e);
86			}
87	tdb	1.3	// start the DataHandler running
88			dh.start();
89			// keep a reference
90			_dataHandler = dh;
91	tdb	1.1	return true;
92			}
93			else {
94			return false;
95			}
96			}
97
98			/**
99			* Stop sending data to the client.
100			*
101			* @return a boolean stating whether the attempt to stop succeeded
102			*/
103			public boolean stopData() {
104	tdb	1.3	if(_dataHandler != null) {
105	tdb	1.1	// deregister the Queue
106	tdb	1.3	_packetSorter.deregister(_dataHandler.getQueue(), _hostList);
107			// stop the DataHandler
108			_dataHandler.shutdown();
109			// destroy the reference
110			_dataHandler = null;
111	tdb	1.1	return true;
112			}
113			else {
114			return false;
115			}
116			}
117
118			/**
119			* Sets the host list for the Client to the requested semi-colon separated
120			* list of hostnames. This will only succeed if we are not sending data.
121			*
122			* @param hostList A semi-colon separated list of hostnames to use.
123			* @return Whether the request succeeded.
124			*/
125			public boolean setHostList(String hostList) {
126	tdb	1.3	if(_dataHandler == null) {
127	tdb	1.1	_hostList = hostList;
128			return true;
129			}
130			else {
131			return false;
132			}
133			}
134
135			/**
136	tdb	1.8	* Disconnect, this will shutdown the data and unhook from
137			* the CORBA ORB.
138			*/
139			public void disconnect() {
140			// close the data handler
141			stopData();
142			// disconnect from the ORB
143			try {
144	tdb	1.9	byte[] oid = _refman.getRootPOA().servant_to_id(this);
145			_refman.getRootPOA().deactivate_object(oid);
146	tdb	1.8	} catch(Exception e) {
147			_logger.write(this.toString(), Logger.ERROR, "disconnect failed: "+e);
148			}
149			}
150
151			/**
152	tdb	1.1	* Overrides the {@link java.lang.Object#toString() Object.toString()}
153			* method to provide clean logging (every class should have this).
154			*
155	tdb	1.17	* This uses the uk.org.iscream.cms.util.NameFormat class
156	tdb	1.1	* to format the toString()
157			*
158			* @return the name of this class and its CVS revision
159			*/
160			public String toString() {
161			return FormatName.getName(
162			_name,
163			getClass().getName(),
164			REVISION);
165			}
166
167			//---PRIVATE METHODS---
168	tdb	1.12
169			/**
170			* Overridden for debugging purposes
171			* to see when an instance of this class
172			* is destroyed
173			*/
174			protected void finalize() throws Throwable {
175			_logger.write(this.toString(), Logger.DEBUG, "finalized by GC");
176			}
177	tdb	1.1
178			//---ACCESSOR/MUTATOR METHODS---
179
180			//---ATTRIBUTES---
181
182			/**
183			* This is the friendly identifier of the
184			* component this class is running in.
185			* eg, a Filter may be called "filter1",
186			* If this class does not have an owning
187			* component, a name from the configuration
188			* can be placed here. This name could also
189			* be changed to null for utility classes.
190			*/
191			private String _name = ClientInterfaceMain.NAME;
192
193			/**
194			* This holds a reference to the
195			* system logger that is being used.
196			*/
197			private Logger _logger = ReferenceManager.getInstance().getLogger();
198	tdb	1.8
199			/**
200			* A reference to the reference manager in use
201			*/
202			private ReferenceManager _refman = ReferenceManager.getInstance();
203	tdb	1.1
204			/**
205			* A reference to the PacketSorter.
206			*/
207			private PacketSorter _packetSorter;
208
209			/**
210			* The host list the Client has requested
211			*/
212			private String _hostList;
213
214			/**
215			* The "servant" part of the client we're connected to.
216			*/
217			private Client _client;
218
219			/**
220	tdb	1.3	* A reference to our DataHandler, if we have one
221	tdb	1.1	*/
222	tdb	1.3	private CorbaDataHandler _dataHandler;
223	tdb	1.6
224			/**
225			* A name to identify the client
226			*/
227			private String _clientname;
228	tdb	1.1
229			//---STATIC ATTRIBUTES---
230
231			}