network.detectors
Class FailureEventDetector

java.lang.Object
  |
  +--network.detectors.EventDetector
        |
        +--network.detectors.FailureEventDetector

All Implemented Interfaces:

java.lang.Runnable, java.io.Serializable

Direct Known Subclasses:

SMSFailureEventDetector

public class FailureEventDetector

extends EventDetector

The FailureEvent Detector can monitor agents and detectors for failure. A detector fails if its TTL expires. An agent fails if all its detectors have failed (TTLs expired). This detector generates FailureEvents.

See Also:

FailureEvent, Serialized Form

Field Summary

(package private) java.util.Hashtable	agentHashtable
(package private) java.util.Hashtable	booleanHashtable
protected java.util.Hashtable	checkPoint
(package private) int	count
private java.lang.String[]	defaultLocalTriggeringEvents
private java.lang.String[]	defaultRemoteTriggeringEvents
(package private) java.util.Hashtable	seqNumbersHashtable
(package private) java.util.Hashtable	subscriberHashtable
(package private) int	THRESHOLD
(package private) long	WRAP_AROUND

Fields inherited from class network.detectors.EventDetector

agentURN, attempts, cred, dbModule, eventIDGenerator, eventTable, host, localTriggeringEvents, printRunningThreadsFlag, remoteTriggeringEvents, reportTable

Constructor Summary

FailureEventDetector(java.util.Hashtable agentHashtable, ConfigObject configObj)
The default constructor.

Method Summary

network.events.Event	createEvent(ajanta.naming.URN fieldAgentURN, java.util.Vector failedDetectorNames, int seq, java.util.Vector sourceURNList)
java.util.Vector	generateEvent(network.events.Event triggeredEvent) generateEvent checks to see if a FailureEvent should be generated.
private int	getDetectorThreshold(ajanta.naming.URN fieldAgentURN, java.lang.String detectorName) This method returns the number of times an event must occur before we generate a FailureEvent.
java.lang.String	getGeneratingEventClassName() Returns the fully-qualified classname of the event that this detector may generate.
private void	handleAgentAliveEvent(network.events.AgentAliveEvent agentAliveEvent)
private java.util.Vector	handleTimerEvent(network.events.TimerEvent timerEvent) e*
void	modifyDetector(java.lang.Object object) This method allows us to customize the detector.
private void	populateBooleanHashtable()

Methods inherited from class network.detectors.EventDetector

getAlarmLevel, getAlertLevel, getLocalTriggeringEventClassNames, getRemoteTriggeringEventClassNames, getSynchronizer, InitializeFields, modifyDetector, populatePatterns, printRunningThreads, run, setAgentURN, setAlarmLevel, setAlertLevel, setDB, setEventIDGenerator, setEventTable, setLocalTriggeringEvents, setRemoteTriggeringEvents, setReportTable, stopDetector, switchOffPrintRunningThreads

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

THRESHOLD

int THRESHOLD

agentHashtable

java.util.Hashtable agentHashtable

booleanHashtable

java.util.Hashtable booleanHashtable

subscriberHashtable

java.util.Hashtable subscriberHashtable

checkPoint

protected java.util.Hashtable checkPoint

count

int count

seqNumbersHashtable

java.util.Hashtable seqNumbersHashtable

WRAP_AROUND

long WRAP_AROUND

defaultLocalTriggeringEvents

private java.lang.String[] defaultLocalTriggeringEvents

defaultRemoteTriggeringEvents

private java.lang.String[] defaultRemoteTriggeringEvents

Constructor Detail

FailureEventDetector

public FailureEventDetector(java.util.Hashtable agentHashtable,
                            ConfigObject configObj)

The default constructor. Takes in a hashtable of agents and detectorStatus elements, each of which will be monitored for failure.

Parameters:

agentHashtable - hashtable, keys agent URNs, values, DetectorStatus vectors.

Method Detail

populateBooleanHashtable

private void populateBooleanHashtable()

Returns:

getGeneratingEventClassName

public java.lang.String getGeneratingEventClassName()

Returns the fully-qualified classname of the event that this detector may generate.

Specified by:

getGeneratingEventClassName in class EventDetector

Returns:

the fully-qualified classname of the event that this detector may generate.

generateEvent

public java.util.Vector generateEvent(network.events.Event triggeredEvent)

generateEvent checks to see if a FailureEvent should be generated. It may be triggered by TimerEvent or AgentAliveEvent. In the case of TimerEvent, we check to see if its Time To Live has expired; if it has, we generate a FailureEvent. In the case of AgentAliveEvent, we will reset the TTL to its default start state if the agent is not in its initial mode.

Specified by:

generateEvent in class EventDetector

Parameters:

triggeredEvent - the event that triggered this detector.

Returns:

the vector of generated FailureEvents.

handleTimerEvent

private java.util.Vector handleTimerEvent(network.events.TimerEvent timerEvent)

e*

Parameters:

timerEvent -

Returns:

createEvent

public network.events.Event createEvent(ajanta.naming.URN fieldAgentURN,
                                        java.util.Vector failedDetectorNames,
                                        int seq,
                                        java.util.Vector sourceURNList)

handleAgentAliveEvent

private void handleAgentAliveEvent(network.events.AgentAliveEvent agentAliveEvent)

Parameters:

agentAliveEvent -

Returns:

getDetectorThreshold

private int getDetectorThreshold(ajanta.naming.URN fieldAgentURN,
                                 java.lang.String detectorName)

This method returns the number of times an event must occur before we generate a FailureEvent.

Parameters:

fieldAgentURN - agent URN

detectorName - fully-qualified detector name

Returns:

modifyDetector

public void modifyDetector(java.lang.Object object)

This method allows us to customize the detector. If passed a ConfigurationChangeObject, the detector will try to add or delete detectors or agents to its monitoring state, based on the setup of the CCO.

Parameters:

object - the ConfigurationChangeObject that controls modification.

Returns:

See Also:

network.ConfigurationChangeObject