server/clientinterface/PacketSorter.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 java.util.*;

/**
 * Receives data from the incoming CORBA servant, places
 * it in a Queue, and then arranges distribution to the
 * DataHandlers.
 * Has extra functionality to send data to DataHandlers
 * on a per-host basis - ie. the Client can request which
 * hosts it would like to listen for.
 *
 * @author  $Author: tdb1 $
 * @version $Id: PacketSorter.java,v 1.4 2001/01/27 23:30:40 tdb1 Exp $
 */
class PacketSorter extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.4 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Creates a new PacketSorter.
     */
    public PacketSorter() {
        _queue = new Queue();
        // startup a monitor on this queue, every minute
        _queue.startMonitor(60*1000, _name);
        _hostMap = new HashMap();
        _allHostsList = new LinkedList();
        _logger.write(toString(), Logger.SYSINIT, "created");
    }
    
//---PUBLIC METHODS---

    /**
     * Method to start the PacketSorter running. This method will
     * loop forever processing and sending data.
     */
    public void run() {
        int qID = _queue.getQueue();
        while(true) {
            // attempt to get some data from the Queue
            String xml = "";
            try {
                xml = (String) _queue.get(qID);
            }
            catch(InvalidQueueException e) {
                _logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
            }
            
            // find out which host this packet is actually for
            XMLPacketMaker xmlPacketMaker = new XMLPacketMaker(xml);
            XMLPacket packet = xmlPacketMaker.createXMLPacket();
            String host = packet.getParam("packet.attributes.machine_name");
            
            // look in the hostMap to see if anyone wants this data
            if(_hostMap.containsKey(host)) {
                LinkedList list = (LinkedList) _hostMap.get(host);
                Iterator i = list.iterator();
                // push the data to the listening Handler's queue
                while(i.hasNext()) {
                    ((Queue) i.next()).add(xml);
                }
            }
            
            // any handler in this list wants all packets, so send
            // it on to them regardless
            Iterator j = _allHostsList.iterator();
            while(j.hasNext()) {
                ((Queue) j.next()).add(xml);
            }
        }
    }
    
    /**
     * Register a DataHandler in the system. This method
     * actually takes a reference to a Queue, which should be
     * a Queue that the DataHandler is making use of.
     * It also takes a hostList, this being a semi-colon
     * seperated list of hosts that the Client the DataHandler
     * is serving has requested. If this list is simply an empty
     * String, it is assumed the Client wants to listen to all
     * host information.
     *
     * @param dhQueue a Queue being used by the DataHandler that is registering
     * @param hostList a semi-colon seperated list of hosts
     */
    public void register(Queue dhQueue, String hostList) {
        // check to see if we want all hosts
        if(hostList.equals("")) {
            _allHostsList.add(dhQueue);
            _logger.write(toString(), Logger.SYSMSG, "registered DataHandler for all hosts");
        }
        else {
            // go through the list of hosts
            StringTokenizer st = new StringTokenizer(hostList, ";");
            while(st.hasMoreTokens()) {
                String host = st.nextToken();
                // see if we already have a list in the map for this host
                if(_hostMap.containsKey(host)) {
                    // we do, so add to it
                    LinkedList list = (LinkedList) _hostMap.get(host);
                    list.add(dhQueue);
                }
                else {
                    // we don't, so create a list and put it in the map
                    LinkedList list = new LinkedList();
                    list.add(dhQueue);
                    _hostMap.put(host, list);
                }
            }
            _logger.write(toString(), Logger.SYSMSG, "registered DataHandler for hosts: "+hostList);
        }
    }
    
    /**
     * Deregister a DataHandler. The DataHandler should give a reference
     * to the Queue it's using, and the *same* hostList it gave when it
     * register. It is imperative that the hostList is the same, otherwise
     * there will be all sorts of problems with lists getting out of sync.
     *
     * NB: Possible future addition would be recording of hostList's.
     *
     * @param dhQueue a Queue being used by the DataHandler that is deregistering
     * @param hostList a semi-colon seperated list of hosts
     */
    public void deregister(Queue dhQueue, String hostList) {
        // go through the list of hosts
        if(hostList.equals("")) {
            _allHostsList.remove(dhQueue);
            _logger.write(toString(), Logger.SYSMSG, "deregistered DataHandler for all hosts");
        }
        else {
            StringTokenizer st = new StringTokenizer(hostList, ";");
            while(st.hasMoreTokens()) {
                String host = st.nextToken();
                // this should in reality always be true, but best check
                if(_hostMap.containsKey(host)) {
                    // get the list and remove the host in question
                    LinkedList list = (LinkedList) _hostMap.get(host);
                    list.remove(dhQueue);
                    // if the list is now empty, we might as well remove it
                    if(list.size()==0) {
                        _hostMap.remove(host);
                    }
                }
            }
            _logger.write(toString(), Logger.SYSMSG, "deregistered DataHandler for hosts: "+hostList);
        }
    }
    
    /**
     * 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---
    
    /**
     * Accessor to return a reference to the Queue object. This
     * is needed so the ClientInterfaceServant can get add data
     * easily.
     *
     * @return a reference to our Queue object.
     */
    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();
    
    /**
     * A reference to the Queue we're using.
     */
    private Queue _queue;
    
    /**
     * A HashMap to store lists of Queue's (in the DataHandlers)
     * in a way that can be easily accessed when data comes in.
     */
    private HashMap _hostMap;
    
    /**
     * A list specifically for a Queue's associated with DataHandlers
     * that want all host information.
     */
    private LinkedList _allHostsList;
    
//---STATIC ATTRIBUTES---

}
Revision:	1.5
Committed:	Mon Feb 12 02:23:52 2001 UTC (23 years, 3 months ago) by tdb
Branch:	MAIN
Changes since 1.4:	+4 -2 lines
Log Message:	Now monitor the Queue here every 60 seconds, reporting back to the Queue in the PacketSorter class.
#	Content
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 java.util.*;
9
10	/**
11	* Receives data from the incoming CORBA servant, places
12	* it in a Queue, and then arranges distribution to the
13	* DataHandlers.
14	* Has extra functionality to send data to DataHandlers
15	* on a per-host basis - ie. the Client can request which
16	* hosts it would like to listen for.
17	*
18	* @author $Author: tdb1 $
19	* @version $Id: PacketSorter.java,v 1.4 2001/01/27 23:30:40 tdb1 Exp $
20	*/
21	class PacketSorter extends Thread {
22
23	//---FINAL ATTRIBUTES---
24
25	/**
26	* The current CVS revision of this class
27	*/
28	public final String REVISION = "$Revision: 1.4 $";
29
30	//---STATIC METHODS---
31
32	//---CONSTRUCTORS---
33
34	/**
35	* Creates a new PacketSorter.
36	*/
37	public PacketSorter() {
38	_queue = new Queue();
39	// startup a monitor on this queue, every minute
40	_queue.startMonitor(60*1000, _name);
41	_hostMap = new HashMap();
42	_allHostsList = new LinkedList();
43	_logger.write(toString(), Logger.SYSINIT, "created");
44	}
45
46	//---PUBLIC METHODS---
47
48	/**
49	* Method to start the PacketSorter running. This method will
50	* loop forever processing and sending data.
51	*/
52	public void run() {
53	int qID = _queue.getQueue();
54	while(true) {
55	// attempt to get some data from the Queue
56	String xml = "";
57	try {
58	xml = (String) _queue.get(qID);
59	}
60	catch(InvalidQueueException e) {
61	_logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
62	}
63
64	// find out which host this packet is actually for
65	XMLPacketMaker xmlPacketMaker = new XMLPacketMaker(xml);
66	XMLPacket packet = xmlPacketMaker.createXMLPacket();
67	String host = packet.getParam("packet.attributes.machine_name");
68
69	// look in the hostMap to see if anyone wants this data
70	if(_hostMap.containsKey(host)) {
71	LinkedList list = (LinkedList) _hostMap.get(host);
72	Iterator i = list.iterator();
73	// push the data to the listening Handler's queue
74	while(i.hasNext()) {
75	((Queue) i.next()).add(xml);
76	}
77	}
78
79	// any handler in this list wants all packets, so send
80	// it on to them regardless
81	Iterator j = _allHostsList.iterator();
82	while(j.hasNext()) {
83	((Queue) j.next()).add(xml);
84	}
85	}
86	}
87
88	/**
89	* Register a DataHandler in the system. This method
90	* actually takes a reference to a Queue, which should be
91	* a Queue that the DataHandler is making use of.
92	* It also takes a hostList, this being a semi-colon
93	* seperated list of hosts that the Client the DataHandler
94	* is serving has requested. If this list is simply an empty
95	* String, it is assumed the Client wants to listen to all
96	* host information.
97	*
98	* @param dhQueue a Queue being used by the DataHandler that is registering
99	* @param hostList a semi-colon seperated list of hosts
100	*/
101	public void register(Queue dhQueue, String hostList) {
102	// check to see if we want all hosts
103	if(hostList.equals("")) {
104	_allHostsList.add(dhQueue);
105	_logger.write(toString(), Logger.SYSMSG, "registered DataHandler for all hosts");
106	}
107	else {
108	// go through the list of hosts
109	StringTokenizer st = new StringTokenizer(hostList, ";");
110	while(st.hasMoreTokens()) {
111	String host = st.nextToken();
112	// see if we already have a list in the map for this host
113	if(_hostMap.containsKey(host)) {
114	// we do, so add to it
115	LinkedList list = (LinkedList) _hostMap.get(host);
116	list.add(dhQueue);
117	}
118	else {
119	// we don't, so create a list and put it in the map
120	LinkedList list = new LinkedList();
121	list.add(dhQueue);
122	_hostMap.put(host, list);
123	}
124	}
125	_logger.write(toString(), Logger.SYSMSG, "registered DataHandler for hosts: "+hostList);
126	}
127	}
128
129	/**
130	* Deregister a DataHandler. The DataHandler should give a reference
131	* to the Queue it's using, and the same hostList it gave when it
132	* register. It is imperative that the hostList is the same, otherwise
133	* there will be all sorts of problems with lists getting out of sync.
134	*
135	* NB: Possible future addition would be recording of hostList's.
136	*
137	* @param dhQueue a Queue being used by the DataHandler that is deregistering
138	* @param hostList a semi-colon seperated list of hosts
139	*/
140	public void deregister(Queue dhQueue, String hostList) {
141	// go through the list of hosts
142	if(hostList.equals("")) {
143	_allHostsList.remove(dhQueue);
144	_logger.write(toString(), Logger.SYSMSG, "deregistered DataHandler for all hosts");
145	}
146	else {
147	StringTokenizer st = new StringTokenizer(hostList, ";");
148	while(st.hasMoreTokens()) {
149	String host = st.nextToken();
150	// this should in reality always be true, but best check
151	if(_hostMap.containsKey(host)) {
152	// get the list and remove the host in question
153	LinkedList list = (LinkedList) _hostMap.get(host);
154	list.remove(dhQueue);
155	// if the list is now empty, we might as well remove it
156	if(list.size()==0) {
157	_hostMap.remove(host);
158	}
159	}
160	}
161	_logger.write(toString(), Logger.SYSMSG, "deregistered DataHandler for hosts: "+hostList);
162	}
163	}
164
165	/**
166	* Overrides the {@link java.lang.Object#toString() Object.toString()}
167	* method to provide clean logging (every class should have this).
168	*
169	* This uses the uk.ac.ukc.iscream.util.NameFormat class
170	* to format the toString()
171	*
172	* @return the name of this class and its CVS revision
173	*/
174	public String toString() {
175	return FormatName.getName(
176	_name,
177	getClass().getName(),
178	REVISION);
179	}
180
181	//---PRIVATE METHODS---
182
183	//---ACCESSOR/MUTATOR METHODS---
184
185	/**
186	* Accessor to return a reference to the Queue object. This
187	* is needed so the ClientInterfaceServant can get add data
188	* easily.
189	*
190	* @return a reference to our Queue object.
191	*/
192	public Queue getQueue() {
193	return _queue;
194	}
195
196	//---ATTRIBUTES---
197
198	/**
199	* This is the friendly identifier of the
200	* component this class is running in.
201	* eg, a Filter may be called "filter1",
202	* If this class does not have an owning
203	* component, a name from the configuration
204	* can be placed here. This name could also
205	* be changed to null for utility classes.
206	*/
207	private String _name = ClientInterfaceMain.NAME;
208
209	/**
210	* This holds a reference to the
211	* system logger that is being used.
212	*/
213	private Logger _logger = ReferenceManager.getInstance().getLogger();
214
215	/**
216	* A reference to the Queue we're using.
217	*/
218	private Queue _queue;
219
220	/**
221	* A HashMap to store lists of Queue's (in the DataHandlers)
222	* in a way that can be easily accessed when data comes in.
223	*/
224	private HashMap _hostMap;
225
226	/**
227	* A list specifically for a Queue's associated with DataHandlers
228	* that want all host information.
229	*/
230	private LinkedList _allHostsList;
231
232	//---STATIC ATTRIBUTES---
233
234	}