server/client/MonitorSkeleton.java

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

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

/**
 * Skeleton class for Monitors
 * This skeleton reads packets from a queue designated 
 * by the extending class, it then feeds the data to the analysePacket
 * method, which the extending class should implement.  The class
 * should then handle the monitoring for that packet.
 *
 * @author  $Author: ajm4 $
 * @version $Id: MonitorSkeleton.java,v 1.10 2001/03/22 23:35:11 ajm4 Exp $
 */
public abstract class MonitorSkeleton extends Thread implements PluginMonitor {

//---FINAL ATTRIBUTES---

    /**
     * The current CVS revision of this class
     */
    public final String REVISION = "$Revision: 1.21 $";
    
//---STATIC METHODS---

//---CONSTRUCTORS---

    /**
     * Constructs and start the monitor reading its data
     */
    public MonitorSkeleton() {
        _logger.write(toString(), Logger.SYSINIT, "started.");
        this.start();
    }

//---PUBLIC METHODS---

    /**
     * Obtains data from the monitors data queue and 
     * passes the packet to the analysePacket method.
     */
    public void run() {
        while(_running) {
            try {
                analysePacket((XMLPacket) getQueue().get(getQueueId()));
            } catch (InvalidQueueException e) {
                _logger.write(this.toString(), Logger.ERROR, "Unable to get queue.");
            }
        }
    }
    
    /**
     * Extending classes should override this method to
     * analyse the given packet for the attribute
     * they are responsible for.
     */
    protected abstract void analysePacket(XMLPacket packet);

    /**
     * Once a Monitor has determined which threshold the given data packet
     * is at, it should then call this method.  This method handles ALL 
     * the alerting logic to determine escalation of alerts.
     * If it decides an alert needs to be send, it will send one using fireAlert.
     *
     * @param newThreshold the threshold that has been determined by the monitor
     * @param attributeName the textual name of the attribute the monitor is responsible for
     * @param reg the register that holds the current alert state for the machine/attribute
     * @param source the source of the alert eg, hostname
     * @param currentValue the data value for the attribute
     */
    protected void processAlert(int newThreshold, String attributeName, Register reg, String source, String currentValue) {
        // decide what threshold level we're on, if we've changed, record that
        if (newThreshold != reg.getLastThresholdLevel()) {
            reg.setLastThresholdLevel(newThreshold);
        }
        // as long as this isn't a normal level
        if(reg.getLastThresholdLevel() != Alert.thresholdNORMAL) {
            // if the time since the last alert is more than the time for
            // its timeout, fire an alert, escalate the alert
            long timeout = reg.getLastAlertTimeout();
            if ((timeout > 0) && (reg.getTimeLastSent() > 0)) {
                if((System.currentTimeMillis() - reg.getTimeLastSent()) > timeout) {
                    int lastAlert = reg.getLastAlertLevel();
                    reg.escalateAlert();
                    reg.setTimeLastSent( System.currentTimeMillis());
                    reg.setLastAlertTimeout(reg.getAlertTimeout(reg.getLastAlertLevel()));
                    fireAlert(reg, lastAlert, source, currentValue, attributeName);
                }
            // if we don't have a timeout configured...we got STRAIGHT to the next level
            } else {
                int lastAlert = reg.getLastAlertLevel();
                reg.escalateAlert();
                reg.setTimeLastSent( System.currentTimeMillis());
                reg.setLastAlertTimeout(reg.getAlertTimeout(reg.getLastAlertLevel()));
                fireAlert(reg, lastAlert, source, currentValue, attributeName);
            }
                
        // we must be on ok, check the timeout value for this
        } else {
            // if we were on an OK alert before, then we don't do anything
            // but if we weren't we only set OK, once the timout of the last 
            // alert has occourd
            if (reg.getLastAlertLevel() != Alert.alertOK) {
                long timeout = reg.getLastAlertTimeout();
                if ((timeout > 0) && (reg.getTimeLastSent() > 0)) {
                    if ((System.currentTimeMillis() - reg.getTimeLastSent()) > timeout) {
                        int lastAlert = reg.getLastAlertLevel();
                        reg.setLastAlertLevel(Alert.alertOK);
                        reg.setTimeLastSent(System.currentTimeMillis());
                        reg.setLastAlertTimeout(timeout);
                        fireAlert(reg, lastAlert,  source, currentValue, attributeName);
                    }
                }
            }
        }
    }

    /**
     * Return the String representation of what the alerter does
     *
     * @return the description
     */
    public abstract String getDescription();


//---PRIVATE METHODS---

    /**
     * Fires an alert.  This creates a new Alert object
     * and populates it with the given alert information.
     * It then adds the alert to the Alerter queue.
     *
     * This method should only be called by the processAlert method.
     *
     * @param reg the register holding the state values for the alert
     * @param source the source of the alert eg, hostname
     * @param currentValue the data value for the attribute
     * @param attributeName the textual name of the attribute the alert is for
     */
    private void fireAlert(Register reg, int lastAlert, String source, String currentValue, String attributeName) {
        int alertLevel = reg.getLastAlertLevel();
        int thresholdLevel = reg.getLastThresholdLevel();
        String thresholdValue = String.valueOf(reg.getThreshold(thresholdLevel));
        String timeout = String.valueOf(reg.getAlertTimeout(reg.getLastAlertLevel()) / 1000);
        // ensures we display a nice thing if its -1.0
        if (thresholdValue.equals("-1.0")) {
            thresholdValue = "-";
        }
        if (alertLevel == Alert.alertOK) {
            timeout = "0";
        }
        Alert alert = new Alert(alertLevel, lastAlert, thresholdLevel, source, thresholdValue, currentValue, attributeName, timeout, reg.getInitialAlertTime());
        _alerterQueue.add(alert);
        _logger.write(toString(), Logger.DEBUG, "Fired alert for source:" + source + " at alert level:" + Alert.alertLevels[alertLevel] + " on:" + attributeName + " for threshold level:" + Alert.thresholdLevels[thresholdLevel] + " at:" +  currentValue + " exceeding threshold of:" +thresholdValue + " next alert sent in:" + timeout + "secs");
    }

//---ACCESSOR/MUTATOR METHODS---

    /**
     * Obtain the queue which contains the data
     * the Monitor is reading.
     * eg, MonitorManager.getInstance().getHeartbeatQueue()
     */
    protected abstract Queue getQueue();
    
    /**
     * Create a queue ID on the feeding
     * data queue
     */
    protected int getQueueId() {
        if (_qID == -1) {
            _qID = getQueue().getQueue();
            _logger.write(toString(), Logger.DEBUG, "Assigned Queue - " + _qID);
        }
        return _qID;
    }

//---ATTRIBUTES---

    /**
     * This holds a reference to the
     * system logger that is being used.
     */
    protected Logger _logger = ReferenceManager.getInstance().getLogger();

    /**
     * A reference to the Alerter queue, into which
     * all new alerts will be placed.
     */
    protected Queue _alerterQueue = AlerterManager.getInstance().getQueue();
    
    /**
     * The ID of the queue the monitor will use.
     * Initially -1, but initialised on first use.
     */
    protected int _qID = -1;
    
    /**
     * The state of the alerter thread
     */
    protected boolean _running = true;

//---STATIC ATTRIBUTES---

}
Revision:	1.11
Committed:	Fri Mar 23 01:32:38 2001 UTC (23 years, 1 month ago) by ajm
Branch:	MAIN
CVS Tags:	PROJECT_COMPLETION
Changes since 1.10:	+75 -4 lines
Log Message:	Lots of commenting to explain their use.
#	Content
1	//---PACKAGE DECLARATION---
2	package uk.org.iscream.client;
3
4	//---IMPORTS---
5	import java.util.HashMap;
6	import uk.org.iscream.client.*;
7	import uk.org.iscream.core.*;
8	import uk.org.iscream.util.*;
9	import uk.org.iscream.componentmanager.*;
10
11	/**
12	* Skeleton class for Monitors
13	* This skeleton reads packets from a queue designated
14	* by the extending class, it then feeds the data to the analysePacket
15	* method, which the extending class should implement. The class
16	* should then handle the monitoring for that packet.
17	*
18	* @author $Author: ajm4 $
19	* @version $Id: MonitorSkeleton.java,v 1.10 2001/03/22 23:35:11 ajm4 Exp $
20	*/
21	public abstract class MonitorSkeleton extends Thread implements PluginMonitor {
22
23	//---FINAL ATTRIBUTES---
24
25	/**
26	* The current CVS revision of this class
27	*/
28	public final String REVISION = "$Revision: 1.21 $";
29
30	//---STATIC METHODS---
31
32	//---CONSTRUCTORS---
33
34	/**
35	* Constructs and start the monitor reading its data
36	*/
37	public MonitorSkeleton() {
38	_logger.write(toString(), Logger.SYSINIT, "started.");
39	this.start();
40	}
41
42	//---PUBLIC METHODS---
43
44	/**
45	* Obtains data from the monitors data queue and
46	* passes the packet to the analysePacket method.
47	*/
48	public void run() {
49	while(_running) {
50	try {
51	analysePacket((XMLPacket) getQueue().get(getQueueId()));
52	} catch (InvalidQueueException e) {
53	_logger.write(this.toString(), Logger.ERROR, "Unable to get queue.");
54	}
55	}
56	}
57
58	/**
59	* Extending classes should override this method to
60	* analyse the given packet for the attribute
61	* they are responsible for.
62	*/
63	protected abstract void analysePacket(XMLPacket packet);
64
65	/**
66	* Once a Monitor has determined which threshold the given data packet
67	* is at, it should then call this method. This method handles ALL
68	* the alerting logic to determine escalation of alerts.
69	* If it decides an alert needs to be send, it will send one using fireAlert.
70	*
71	* @param newThreshold the threshold that has been determined by the monitor
72	* @param attributeName the textual name of the attribute the monitor is responsible for
73	* @param reg the register that holds the current alert state for the machine/attribute
74	* @param source the source of the alert eg, hostname
75	* @param currentValue the data value for the attribute
76	*/
77	protected void processAlert(int newThreshold, String attributeName, Register reg, String source, String currentValue) {
78	// decide what threshold level we're on, if we've changed, record that
79	if (newThreshold != reg.getLastThresholdLevel()) {
80	reg.setLastThresholdLevel(newThreshold);
81	}
82	// as long as this isn't a normal level
83	if(reg.getLastThresholdLevel() != Alert.thresholdNORMAL) {
84	// if the time since the last alert is more than the time for
85	// its timeout, fire an alert, escalate the alert
86	long timeout = reg.getLastAlertTimeout();
87	if ((timeout > 0) && (reg.getTimeLastSent() > 0)) {
88	if((System.currentTimeMillis() - reg.getTimeLastSent()) > timeout) {
89	int lastAlert = reg.getLastAlertLevel();
90	reg.escalateAlert();
91	reg.setTimeLastSent( System.currentTimeMillis());
92	reg.setLastAlertTimeout(reg.getAlertTimeout(reg.getLastAlertLevel()));
93	fireAlert(reg, lastAlert, source, currentValue, attributeName);
94	}
95	// if we don't have a timeout configured...we got STRAIGHT to the next level
96	} else {
97	int lastAlert = reg.getLastAlertLevel();
98	reg.escalateAlert();
99	reg.setTimeLastSent( System.currentTimeMillis());
100	reg.setLastAlertTimeout(reg.getAlertTimeout(reg.getLastAlertLevel()));
101	fireAlert(reg, lastAlert, source, currentValue, attributeName);
102	}
103
104	// we must be on ok, check the timeout value for this
105	} else {
106	// if we were on an OK alert before, then we don't do anything
107	// but if we weren't we only set OK, once the timout of the last
108	// alert has occourd
109	if (reg.getLastAlertLevel() != Alert.alertOK) {
110	long timeout = reg.getLastAlertTimeout();
111	if ((timeout > 0) && (reg.getTimeLastSent() > 0)) {
112	if ((System.currentTimeMillis() - reg.getTimeLastSent()) > timeout) {
113	int lastAlert = reg.getLastAlertLevel();
114	reg.setLastAlertLevel(Alert.alertOK);
115	reg.setTimeLastSent(System.currentTimeMillis());
116	reg.setLastAlertTimeout(timeout);
117	fireAlert(reg, lastAlert, source, currentValue, attributeName);
118	}
119	}
120	}
121	}
122	}
123
124	/**
125	* Return the String representation of what the alerter does
126	*
127	* @return the description
128	*/
129	public abstract String getDescription();
130
131
132	//---PRIVATE METHODS---
133
134	/**
135	* Fires an alert. This creates a new Alert object
136	* and populates it with the given alert information.
137	* It then adds the alert to the Alerter queue.
138	*
139	* This method should only be called by the processAlert method.
140	*
141	* @param reg the register holding the state values for the alert
142	* @param source the source of the alert eg, hostname
143	* @param currentValue the data value for the attribute
144	* @param attributeName the textual name of the attribute the alert is for
145	*/
146	private void fireAlert(Register reg, int lastAlert, String source, String currentValue, String attributeName) {
147	int alertLevel = reg.getLastAlertLevel();
148	int thresholdLevel = reg.getLastThresholdLevel();
149	String thresholdValue = String.valueOf(reg.getThreshold(thresholdLevel));
150	String timeout = String.valueOf(reg.getAlertTimeout(reg.getLastAlertLevel()) / 1000);
151	// ensures we display a nice thing if its -1.0
152	if (thresholdValue.equals("-1.0")) {
153	thresholdValue = "-";
154	}
155	if (alertLevel == Alert.alertOK) {
156	timeout = "0";
157	}
158	Alert alert = new Alert(alertLevel, lastAlert, thresholdLevel, source, thresholdValue, currentValue, attributeName, timeout, reg.getInitialAlertTime());
159	_alerterQueue.add(alert);
160	_logger.write(toString(), Logger.DEBUG, "Fired alert for source:" + source + " at alert level:" + Alert.alertLevels[alertLevel] + " on:" + attributeName + " for threshold level:" + Alert.thresholdLevels[thresholdLevel] + " at:" + currentValue + " exceeding threshold of:" +thresholdValue + " next alert sent in:" + timeout + "secs");
161	}
162
163	//---ACCESSOR/MUTATOR METHODS---
164
165	/**
166	* Obtain the queue which contains the data
167	* the Monitor is reading.
168	* eg, MonitorManager.getInstance().getHeartbeatQueue()
169	*/
170	protected abstract Queue getQueue();
171
172	/**
173	* Create a queue ID on the feeding
174	* data queue
175	*/
176	protected int getQueueId() {
177	if (_qID == -1) {
178	_qID = getQueue().getQueue();
179	_logger.write(toString(), Logger.DEBUG, "Assigned Queue - " + _qID);
180	}
181	return _qID;
182	}
183
184	//---ATTRIBUTES---
185
186	/**
187	* This holds a reference to the
188	* system logger that is being used.
189	*/
190	protected Logger _logger = ReferenceManager.getInstance().getLogger();
191
192	/**
193	* A reference to the Alerter queue, into which
194	* all new alerts will be placed.
195	*/
196	protected Queue _alerterQueue = AlerterManager.getInstance().getQueue();
197
198	/**
199	* The ID of the queue the monitor will use.
200	* Initially -1, but initialised on first use.
201	*/
202	protected int _qID = -1;
203
204	/**
205	* The state of the alerter thread
206	*/
207	protected boolean _running = true;
208
209	//---STATIC ATTRIBUTES---
210
211	}