gov.sns.tools.correlator
Class Correlator

java.lang.Object
  |
  +--gov.sns.tools.correlator.Correlator

Direct Known Subclasses:

ChannelCorrelator

public abstract class Correlator

extends java.lang.Object

The Correlator is the class that is used to setup monitoring of correlated events. It is the sole entry point to the outside world. When correlations are found, the Correlator broadcasts the correlation. Note that all time is in seconds unless otherwise stated.

Field Summary

protected double	_binTimespan
protected CorrelationTester	correlationTester
protected MessageCenter	localCenter

Constructor Summary

Correlator(double aBinTimespan)
Creates new Correlator

Correlator(double aBinTimespan, CorrelationFilter aFilter)
Correlator constructor

Method Summary

void	addListener(CorrelationNotice listener) Register the listener as a receiver of Correlation notices from this correlator.
protected void	addSource(java.lang.Object source, java.lang.String sourceName) Add a source to monitor.
protected void	addSource(java.lang.Object source, java.lang.String sourceName, RecordFilter recordFilter) Add a source to monitor.
double	binTimespan() maximum time span allowed for events to be considered correlated
void	dispose() Dispose of the correlator and its overhead
Correlation	fetchCorrelationWithTimeout(double aTimeout) fetchCorrelationWithTimeout() is a convenience method that allows the user a simple way to fetch a correlation without handling events and implementing a listener.
java.util.Collection	getNamesOfSources() Get all the names of all the sources managed by this correlator
protected java.util.Collection	getSourceAgents() Get all of the channel agents managed by this correlator
boolean	hasSource(java.lang.String sourceName) See if we already manage this channel
boolean	isRunning() Determine if the correlator is running
void	monitorWithTimeout(double timeout) Monitor and post the best partial correlation if the timeout is exceeded.
protected abstract SourceAgent	newSourceAgent(java.lang.Object source, java.lang.String sourceName, RecordFilter recordFilter)
int	numSources() Number of channels being managed
void	pulseMonitorWithTimeout(double timeout) Monitor until the timeout or until a complete correlation is found
protected void	registerEvents() Register for notices.
void	removeAllSources() Stop managing all registered sources
void	removeListener(CorrelationNotice listener) Unregister the listener as a receiver of Correlation notices from this correlator.
void	removeSource(java.lang.String sourceName) Stop managing the specified source.
void	setBinTimespan(double timespan) Set the maximum time span allowed for events to be considered correlated
void	setCorrelationFilter(CorrelationFilter newFilter) Set the correlation filter to the one specified.
void	startMonitoring() Start monitoring the managed sources.
void	stopMonitoring() Stop monitoring the managed sources.

Methods inherited from class java.lang.Object

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

Field Detail

localCenter

protected MessageCenter localCenter

_binTimespan

protected double _binTimespan

correlationTester

protected CorrelationTester correlationTester

Constructor Detail

Correlator

public Correlator(double aBinTimespan)

Creates new Correlator

Correlator

public Correlator(double aBinTimespan,
                  CorrelationFilter aFilter)

Correlator constructor

Method Detail

registerEvents

protected void registerEvents()

Register for notices.

addListener

public void addListener(CorrelationNotice listener)

Register the listener as a receiver of Correlation notices from this correlator.

removeListener

public void removeListener(CorrelationNotice listener)

Unregister the listener as a receiver of Correlation notices from this correlator.

binTimespan

public double binTimespan()

maximum time span allowed for events to be considered correlated

setBinTimespan

public void setBinTimespan(double timespan)

Set the maximum time span allowed for events to be considered correlated

setCorrelationFilter

public void setCorrelationFilter(CorrelationFilter newFilter)

Set the correlation filter to the one specified.

Parameters:

newFilter - The correlation filter to use.

getSourceAgents

protected java.util.Collection getSourceAgents()

Get all of the channel agents managed by this correlator

getNamesOfSources

public java.util.Collection getNamesOfSources()

Get all the names of all the sources managed by this correlator

numSources

public int numSources()

Number of channels being managed

hasSource

public boolean hasSource(java.lang.String sourceName)

See if we already manage this channel

addSource

protected void addSource(java.lang.Object source,
                         java.lang.String sourceName)

Add a source to monitor. The name provided with each source must be unique to that source. Subclasses need to wrap this method to enforce the source type.

addSource

protected void addSource(java.lang.Object source,
                         java.lang.String sourceName,
                         RecordFilter recordFilter)

Add a source to monitor. If we already monitor a source as determined by the source name, then do nothing. The record filter is used to determine whether or not to accept a reading of the specified source when the event is handled. You can create your own custom filter or use a pre-built one. Subclasses need to wrap this method to enforce the source type.

newSourceAgent

protected abstract SourceAgent newSourceAgent(java.lang.Object source,
                                              java.lang.String sourceName,
                                              RecordFilter recordFilter)

removeSource

public void removeSource(java.lang.String sourceName)

Stop managing the specified source.

removeAllSources

public void removeAllSources()

Stop managing all registered sources

pulseMonitorWithTimeout

public void pulseMonitorWithTimeout(double timeout)

Monitor until the timeout or until a complete correlation is found

Parameters:

timeout - time to wait in seconds

monitorWithTimeout

public void monitorWithTimeout(double timeout)

Monitor and post the best partial correlation if the timeout is exceeded. The timeout is rescheduled after every post.

Parameters:

timeout - time to wait in seconds

startMonitoring

public void startMonitoring()

Start monitoring the managed sources.

stopMonitoring

public void stopMonitoring()

Stop monitoring the managed sources.

isRunning

public boolean isRunning()

Determine if the correlator is running

Returns:

true if the correlator is running and false otherwise.

dispose

public void dispose()

Dispose of the correlator and its overhead

fetchCorrelationWithTimeout

public Correlation fetchCorrelationWithTimeout(double aTimeout)

fetchCorrelationWithTimeout() is a convenience method that allows the user a simple way to fetch a correlation without handling events and implementing a listener. The method spawns a fetch and blocks until a correlation is retrieved or the timeout has expired. The resulting correlation is returned. If no correlation was found within the timeout, null is returned.