server/client/AlerterManager.java

//---PACKAGE DECLARATION---
package uk.org.iscream.client;

//---IMPORTS---
import uk.org.iscream.componentmanager.*;
import uk.org.iscream.core.*;
import uk.org.iscream.util.*;
import java.util.*;

/**
 * A manager for the Monitors.
 *
 * @author  $Author: tdb1 $
 * @version $Id: AlerterManager.java,v 1.2 2001/03/13 02:19:41 tdb1 Exp $
 */
class AlerterManager extends Thread {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public static final String REVISION = "$Revision: 1.2 $";
    
//---STATIC METHODS---
    
    /**
     * Return a reference to the single class.
     * Construct it if it does not already exist, otherwise just return the reference.
     */
    public static AlerterManager getInstance() {
        if (_instance == null){
            _instance = new AlerterManager();
        }
        return _instance;
    }

//---CONSTRUCTORS---

    private AlerterManager() {
        // set our name
        setName("client.AlerterManager");
        
        _queue = ClientMain._alerterQueue;
        _qID = _queue.getQueue();
        _logger.write(toString(), Logger.SYSINIT, "Initialising");
        _logger.write(toString(), Logger.SYSMSG, "Creating alerter pipeline for plugin alerters ...");
        
        // get the configuration for this plug-in setup
        Configuration config = _refman.getCM().getConfiguration(_name);
        String pluginsPackage = config.getProperty("Alerter.PluginsPackage");
        String pluginsList = config.getProperty("Alerter.Plugins");
        
        StringTokenizer st = new StringTokenizer(pluginsList, ";");
        
        while(st.hasMoreTokens()) {
            String className = pluginsPackage + "." + st.nextToken() + _suffix;
            _logger.write(toString(), Logger.DEBUG, "Attempting to create plugin: "+className);
            
            // Create an instance of the specified PluginAlerter to include
            // within the alerterPipe.  Add it to the alerterPipeline
            try {
                PluginAlerter pa = (PluginAlerter)ClassLoader.getSystemClassLoader().loadClass(className).newInstance();
                _alerterPipeline.add(pa);
                _logger.write(toString(), Logger.DEBUG, "Added alerter: "+className+" ("+pa.getDescription()+")");
            }
            catch (InstantiationException e){
                _logger.write(toString(), Logger.ERROR, "Failed to instantiate "+className+" to the plugin alerter pipeline.");
                _logger.write(toString(), Logger.ERROR, e.getMessage());
            }
            catch (Exception e){
                _logger.write(toString(), Logger.ERROR, "Failed to add "+className+" to the plugin alerter pipeline.");
                _logger.write(toString(), Logger.ERROR, e.toString());
            }
        }
        _logger.write(toString(), Logger.SYSMSG, "The alerter pipeline has been set up with "+_alerterPipeline.size()+" plugin alerters.");
    }

//---PUBLIC METHODS---
    
    public void run() {
        
        boolean run=true;
        while(run) {
            // attempt to get some data from the Queue
            Alert alert = null;
            try {
                alert = (Alert) _queue.get(_qID);
            }
            catch(InvalidQueueException e) {
                _logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
            }
            
            // for each alerter in the pipeline...
            Iterator pluginAlerters = _alerterPipeline.iterator();
            while (pluginAlerters.hasNext()){
                PluginAlerter alerter = (PluginAlerter)pluginAlerters.next();
                alerter.sendAlert(alert);
            }
        }
    }

    /**
     * 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.FormatName 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 = ClientMain.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 our Queue
     */
    private Queue _queue;
    
    /**
     * Our queue ID
     */
    private int _qID;
    
    /**
     * file name suffix for plugin alerter classes:
     */
    private final String _suffix = "__Alerter";
    
    /**
     * LinkedList for holding the PluginAlerter objects (the pipeline).
     */
    private LinkedList _alerterPipeline = new LinkedList();

//---STATIC ATTRIBUTES---

    /**
     * A reference to the single instance of this class
     */
    private static AlerterManager _instance;

}
Revision:	1.3
Committed:	Wed Mar 14 23:25:29 2001 UTC (23 years, 2 months ago) by tdb
Branch:	MAIN
Changes since 1.2:	+8 -8 lines
Log Message:	The whole server package structure has been changed. Old Package: uk.ac.ukc.iscream.* New Package: uk.org.iscream.*
#	Content
1	//---PACKAGE DECLARATION---
2	package uk.org.iscream.client;
3
4	//---IMPORTS---
5	import uk.org.iscream.componentmanager.*;
6	import uk.org.iscream.core.*;
7	import uk.org.iscream.util.*;
8	import java.util.*;
9
10	/**
11	* A manager for the Monitors.
12	*
13	* @author $Author: tdb1 $
14	* @version $Id: AlerterManager.java,v 1.2 2001/03/13 02:19:41 tdb1 Exp $
15	*/
16	class AlerterManager extends Thread {
17
18	//---FINAL ATTRIBUTES---
19
20	/**
21	* The current CVS revision of this class
22	*/
23	public static final String REVISION = "$Revision: 1.2 $";
24
25	//---STATIC METHODS---
26
27	/**
28	* Return a reference to the single class.
29	* Construct it if it does not already exist, otherwise just return the reference.
30	*/
31	public static AlerterManager getInstance() {
32	if (_instance == null){
33	_instance = new AlerterManager();
34	}
35	return _instance;
36	}
37
38	//---CONSTRUCTORS---
39
40	private AlerterManager() {
41	// set our name
42	setName("client.AlerterManager");
43
44	_queue = ClientMain._alerterQueue;
45	_qID = _queue.getQueue();
46	_logger.write(toString(), Logger.SYSINIT, "Initialising");
47	_logger.write(toString(), Logger.SYSMSG, "Creating alerter pipeline for plugin alerters ...");
48
49	// get the configuration for this plug-in setup
50	Configuration config = _refman.getCM().getConfiguration(_name);
51	String pluginsPackage = config.getProperty("Alerter.PluginsPackage");
52	String pluginsList = config.getProperty("Alerter.Plugins");
53
54	StringTokenizer st = new StringTokenizer(pluginsList, ";");
55
56	while(st.hasMoreTokens()) {
57	String className = pluginsPackage + "." + st.nextToken() + _suffix;
58	_logger.write(toString(), Logger.DEBUG, "Attempting to create plugin: "+className);
59
60	// Create an instance of the specified PluginAlerter to include
61	// within the alerterPipe. Add it to the alerterPipeline
62	try {
63	PluginAlerter pa = (PluginAlerter)ClassLoader.getSystemClassLoader().loadClass(className).newInstance();
64	_alerterPipeline.add(pa);
65	_logger.write(toString(), Logger.DEBUG, "Added alerter: "+className+" ("+pa.getDescription()+")");
66	}
67	catch (InstantiationException e){
68	_logger.write(toString(), Logger.ERROR, "Failed to instantiate "+className+" to the plugin alerter pipeline.");
69	_logger.write(toString(), Logger.ERROR, e.getMessage());
70	}
71	catch (Exception e){
72	_logger.write(toString(), Logger.ERROR, "Failed to add "+className+" to the plugin alerter pipeline.");
73	_logger.write(toString(), Logger.ERROR, e.toString());
74	}
75	}
76	_logger.write(toString(), Logger.SYSMSG, "The alerter pipeline has been set up with "+_alerterPipeline.size()+" plugin alerters.");
77	}
78
79	//---PUBLIC METHODS---
80
81	public void run() {
82
83	boolean run=true;
84	while(run) {
85	// attempt to get some data from the Queue
86	Alert alert = null;
87	try {
88	alert = (Alert) _queue.get(_qID);
89	}
90	catch(InvalidQueueException e) {
91	_logger.write(toString(), Logger.ERROR, "Queue failure: "+e);
92	}
93
94	// for each alerter in the pipeline...
95	Iterator pluginAlerters = _alerterPipeline.iterator();
96	while (pluginAlerters.hasNext()){
97	PluginAlerter alerter = (PluginAlerter)pluginAlerters.next();
98	alerter.sendAlert(alert);
99	}
100	}
101	}
102
103	/**
104	* Overrides the {@link java.lang.Object#toString() Object.toString()}
105	* method to provide clean logging (every class should have this).
106	*
107	* This uses the uk.org.iscream.util.FormatName class
108	* to format the toString()
109	*
110	* @return the name of this class and its CVS revision
111	*/
112	public String toString() {
113	return FormatName.getName(
114	_name,
115	getClass().getName(),
116	REVISION);
117	}
118
119	//---PRIVATE METHODS---
120
121	//---ACCESSOR/MUTATOR METHODS---
122
123	//---ATTRIBUTES---
124
125	/**
126	* This is the friendly identifier of the
127	* component this class is running in.
128	* eg, a Filter may be called "filter1",
129	* If this class does not have an owning
130	* component, a name from the configuration
131	* can be placed here. This name could also
132	* be changed to null for utility classes.
133	*/
134	private String _name = ClientMain.NAME;
135
136	/**
137	* This holds a reference to the
138	* system logger that is being used.
139	*/
140	private Logger _logger = ReferenceManager.getInstance().getLogger();
141
142	/**
143	* A reference to the reference manager in use
144	*/
145	private ReferenceManager _refman = ReferenceManager.getInstance();
146
147	/**
148	* A reference to our Queue
149	*/
150	private Queue _queue;
151
152	/**
153	* Our queue ID
154	*/
155	private int _qID;
156
157	/**
158	* file name suffix for plugin alerter classes:
159	*/
160	private final String _suffix = "__Alerter";
161
162	/**
163	* LinkedList for holding the PluginAlerter objects (the pipeline).
164	*/
165	private LinkedList _alerterPipeline = new LinkedList();
166
167	//---STATIC ATTRIBUTES---
168
169	/**
170	* A reference to the single instance of this class
171	*/
172	private static AlerterManager _instance;
173
174	}