org.lsst.ccs.framework

Class Module

java.lang.Object

java.util.Observable

org.lsst.ccs.framework.Module

All Implemented Interfaces:

Observer, ConfigurationBulkChangeHandler, Configurable, HasLifecycle, SignalHandler, UsesSubsystem

Direct Known Subclasses:

MonMain

public class Module
extends Observable
implements HasLifecycle, ConfigurationBulkChangeHandler, Observer, Configurable, SignalHandler

Building block for a ModularSubsystem. These are Configurable with additional facilities:

• Observable features
• a Timer to publish data at regular intervals
• SignalHandler capabilities (and corresponding commands)
• specific commands

Author:

aubourg

notes: module driver, sends to functionnal modules such as calibration iquestion: how are the module sindependants have a look at sampler ....

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	Module.ValueUpdate

Nested classes/interfaces inherited from interface org.lsst.ccs.framework.Configurable

Configurable.Environment

Field Summary

Fields

Modifier and Type	Field and Description
protected String	name Deprecated. the name of this component can be accessed via getName() Use your own field if you wish to assign it.
protected int	nObserverThreads
protected int	tickMillis

Constructor Summary

Constructors

Constructor and Description
Module()
Module(int tickMillis)
Module(String name) Deprecated. the name can be accessed via getName()
Module(String name, int tickMillis) Deprecated. the name can be accessed via getName()

Method Summary

Modifier and Type	Method and Description
int	getNObserverThreads() Deprecated. it does not provide any useful information
List<Observable>	getObservables() Returns the list of Observable this module is observing.
int	getTickMillis()
void	init() Called from the enclosing Subsystem at initialization phase.
void	initModule() To be overriden by individual modules.
void	listens(Observable... observs) Adds a list of observables for this module.
void	processUpdate(Observable source, Module.ValueUpdate update) This method should be overriden to handle change to properties of watched modules
void	sendSignal(String signalString) command to send a signal.
void	sendSignalWithTimeLimit(String signalString, long expectedMaxDelay) command to send a signal with a delay for execution.
void	setNObserverThreads(int observerThreads) Deprecated.
void	setObservables(List<Observable> l) Adds a list of observables for this module.
void	setTickMillis(int tickMillis) Changes the periodic wake up time.
void	shutdownNow() added for tying to unstuck ExcecutorService.
TreeWalkerDiag	signal(Signal sig) this method is intended for overriding: the module receives an out of band signal.
void	startTicking() If there is a scheduled wake up (that is if the tickMillis is more than zero) then the ticking starts.
void	tick()
void	update(Observable o, Object arg) Synchronous update.

Methods inherited from class java.util.Observable

addObserver, clearChanged, countObservers, deleteObserver, deleteObservers, hasChanged, notifyObservers, notifyObservers, setChanged

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.lsst.ccs.framework.Configurable

change, dropSubmittedChanges, getChildren, getComponentByName, getEnvironment, getParent, getParentObject, getSubmittedChanges, isParameterConfigurable, printConfigurableParameters, setBulkParameter, submitChange, submitChanges, validateBulkChange

Methods inherited from interface org.lsst.ccs.config.ConfigurationBulkChangeHandler

setParameterBulk

Methods inherited from interface org.lsst.ccs.framework.HasLifecycle

postStart, start

Methods inherited from interface org.lsst.ccs.UsesSubsystem

getComponentConfigurationEnvironment, getComponentLookup, getName, getSubsystem

Field Detail

name

@Deprecated
protected String name

Deprecated. the name of this component can be accessed via getName() Use your own field if you wish to assign it.

nObserverThreads

protected int nObserverThreads

tickMillis

@ConfigurationParameter
protected int tickMillis

Constructor Detail

Module

public Module()

Module

public Module(int tickMillis)

Module

@Deprecated
public Module(String name,
                          int tickMillis)

Deprecated. the name can be accessed via getName()

Parameters:

name -

tickMillis -

Module

@Deprecated
public Module(String name)

Deprecated. the name can be accessed via getName()

Parameters:

name -

Method Detail

setObservables

public void setObservables(List<Observable> l)

Adds a list of observables for this module.

Parameters:

l - the list of Observable to add

listens

public void listens(Observable... observs)

Adds a list of observables for this module.

Parameters:

observs - one or more Observable to add

getObservables

public List<Observable> getObservables()

Returns the list of Observable this module is observing.

Returns:

a list of

setTickMillis

@ConfigurationParameterChanger(propertyName="tickMillis")
public void setTickMillis(int tickMillis)

Changes the periodic wake up time. The tick method will be called every tickMillis ms.

if called before startup this method just fix the tick frequency (the module wil later "tick" at this rate) .

if called after startup then will change the ticking rate
in that case the ticking will change but new rate will be effective after a delay of "old rate"

Parameters:

tickMillis -

getTickMillis

public int getTickMillis()

setNObserverThreads

@Deprecated
public void setNObserverThreads(int observerThreads)

Deprecated.

Parameters:

observerThreads -

getNObserverThreads

@Deprecated
public int getNObserverThreads()

Deprecated. it does not provide any useful information

Returns:

the number of threads dedicated to process observer updates (inconsistent)

init

public final void init()

Description copied from interface: HasLifecycle

Called from the enclosing Subsystem at initialization phase. At the time it is called, connection to the messaging layer is not yet done, so there should be no attempt to send messages in the body of this method. Configuration for message listening can nevertheless be done here, such as adding MessageListener objects.

It is unnecessary to call super.init()

Specified by:

init in interface HasLifecycle

initModule

public void initModule()

To be overriden by individual modules. Called after all parameters have been set from XML file.

startTicking

public final void startTicking()

If there is a scheduled wake up (that is if the tickMillis is more than zero) then the ticking starts. This method is called on every module after the subsystem is itself ready to listen to commands.

update

public void update(Observable o,
                   Object arg)

Synchronous update. Do not override, override processUpdate. Should we make it final?

Specified by:

update in interface Observer

processUpdate

public void processUpdate(Observable source,
                          Module.ValueUpdate update)

This method should be overriden to handle change to properties of watched modules

Parameters:

source - the module

update - the update message, containing property name and new value

tick

public void tick()

shutdownNow

public void shutdownNow()

added for tying to unstuck ExcecutorService. REVIEW : does it need to be stopped explicitely since it is handled by the scheduler ?

Specified by:

shutdownNow in interface HasLifecycle

signal

public TreeWalkerDiag signal(Signal sig)

this method is intended for overriding: the module receives an out of band signal. Beware this code is executed in a different thread (take care of threading issued when overriding)

Specified by:

signal in interface SignalHandler

Parameters:

sig -

Returns:

one of the TreeWalkerDiag options to tell the subsystem to continue to call this on child components or not.

sendSignal

@Command(description="will propagate signal to Module and its children ",
         type=SIGNAL)
public void sendSignal(String signalString)

command to send a signal.

Parameters:

signalString - string representing a member of an enum of type SignalLevel

sendSignalWithTimeLimit

@Command(description="will propagate signal to Module and its children with  an expected maximum delay",
         type=SIGNAL)
public void sendSignalWithTimeLimit(String signalString,
                                                                                                                                                                   long expectedMaxDelay)

command to send a signal with a delay for execution.

Parameters:

signalString - string representing a member of an enum of type SignalLevel

expectedMaxDelay -