PamguardMVC
Class ThreadedObserver

java.lang.Object
  PamguardMVC.ThreadedObserver

All Implemented Interfaces:

PamObserver

public class ThreadedObserver
extends java.lang.Object
implements PamObserver

This is a decorator class for PamObservers which intercepts any data being sent to that observer and puts the data into a list which will then be re-read in a separate thread, rather than sending if for direct execution.

There is a bit of jiggledy piggledy to get the data history times right since they may need to be extended slightly to allow for data that are not yet used.

Author:

Doug Gillespie

Nested Class Summary

(package private) class

ThreadedObserver.NewObserverThread New observer thread.

Field Summary

private java.util.List<PamDataUnit>	dataUnitList
private boolean	emptyRead
private int	jitterSleep
private boolean	killThread
private int	maxJitter
private int	maxQueSize
private ThreadedObserver.NewObserverThread	newObserverThread
private java.lang.Thread	observerThread
private PamObservable	pamObservable
private PamObserver	singleThreadObserver

Constructor Summary

ThreadedObserver(PamObservable pamObservable, PamObserver singleThreadObserver)

Method Summary

private boolean	canMultiThread() Not possible to multi thread when data come from a sound file, do don't try.
int	getInterThreadListSize()
java.lang.String	getObserverName()
PamObserver	getObserverObject()
long	getRequiredDataHistory(PamObservable o, java.lang.Object arg)
PamObserver	getSingleThreadObserver()
boolean	isEmptyRead()
void	masterClockUpdate(long milliSeconds, long sampleNumber)
void	noteNewSettings()
void	removeObservable(PamObservable o) called when an Observable (PamDataBlock) is removed from the system
void	setSampleRate(float sampleRate, boolean notify) New sample rate
void	update(PamObservable o, PamDataUnit arg) Informs the PamObserver that new data have been added to the Observable class

Methods inherited from class java.lang.Object

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

Field Detail

singleThreadObserver

private PamObserver singleThreadObserver

pamObservable

private PamObservable pamObservable

dataUnitList

private java.util.List<PamDataUnit> dataUnitList

newObserverThread

private ThreadedObserver.NewObserverThread newObserverThread

observerThread

private java.lang.Thread observerThread

killThread

private volatile boolean killThread

emptyRead

private volatile boolean emptyRead

maxQueSize

private int maxQueSize

maxJitter

private int maxJitter

jitterSleep

private int jitterSleep

Constructor Detail

ThreadedObserver

public ThreadedObserver(PamObservable pamObservable,
                        PamObserver singleThreadObserver)

Method Detail

getObserverObject

public PamObserver getObserverObject()

Specified by:

getObserverObject in interface PamObserver

Returns:

the actual observer. In most cases concrete classes will just return 'this' in response. The exception is the Threaded observer, which will return the single thread observer.

getSingleThreadObserver

public PamObserver getSingleThreadObserver()

getObserverName

public java.lang.String getObserverName()

Specified by:

getObserverName in interface PamObserver

getRequiredDataHistory

public long getRequiredDataHistory(PamObservable o,
                                   java.lang.Object arg)

Specified by:

getRequiredDataHistory in interface PamObserver

Parameters:

o - PamObservable class requiring the data

arg - optional argument from PamObservable

Returns:

time in milliseconds requried by data held in PamObservable

getInterThreadListSize

public int getInterThreadListSize()

noteNewSettings

public void noteNewSettings()

Specified by:

noteNewSettings in interface PamObserver

removeObservable

public void removeObservable(PamObservable o)

Description copied from interface: PamObserver

called when an Observable (PamDataBlock) is removed from the system

Specified by:

removeObservable in interface PamObserver

setSampleRate

public void setSampleRate(float sampleRate,
                          boolean notify)

Description copied from interface: PamObserver

New sample rate

Specified by:

setSampleRate in interface PamObserver

notify - Notify other PamObservers and PamObservables in the chain.

masterClockUpdate

public void masterClockUpdate(long milliSeconds,
                              long sampleNumber)

Specified by:

masterClockUpdate in interface PamObserver

update

public void update(PamObservable o,
                   PamDataUnit arg)

Description copied from interface: PamObserver

Informs the PamObserver that new data have been added to the Observable class

Specified by:

update in interface PamObserver

Parameters:

o - Reference to the Observable (a PamDataBlock)

arg - Reference to the new PamDataUnit

canMultiThread

private boolean canMultiThread()

Not possible to multi thread when data come from a sound file, do don't try. Can leave the objects wrapped up in the decorator but just pass the data on, rather than multi threading it.

Returns:

isEmptyRead

public boolean isEmptyRead()