de.hawhamburg.reachability.registry

Class Registry

java.lang.Object

java.lang.Thread

de.hawhamburg.reachability.registry.Registry

All Implemented Interfaces:

StopableObject, java.lang.Runnable

public class Registry
extends java.lang.Thread
implements StopableObject

Sends register request and listens for new component registrations.

This registry service sends and initial registration request over the ActiveMQ to invite all active agents to send their registrations. This service establishes the systems structure via the ActiveMQ and manages their communication afterwards. This may be required if there are for example two sensor agents which supply data for the same context dimension. In this case, the first registration wins until the user switches the activated sensor agent by using the configuration user interface.

Version:

"2013.42"

Author:

"Malte Kantak <malte.kantak@hotmail.de>"

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Random	rand A central random object.
private de.hawhamburg.livingplace.messaging.activemq.wrapper.LPSubscriber	registryTopic Listener for register messages.
private de.hawhamburg.livingplace.messaging.activemq.wrapper.LPPublisher	requestRegistryTopic Publisher for register requests.
private boolean	shutDown Determines whether the method shutDown() has been called or not.
private ReachabilityWorker	systemAgent The worker which called this property service.

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

Constructors

Constructor and Description
Registry() Initializes a new Registry object.
Registry(ReachabilityWorker worker) Initializes a new Registry object with an ReachabilityWorker.

Method Summary

Methods

Modifier and Type	Method and Description
private void	end() Gracefully ends the system by disconnecting all open ActiveMQ connections.
private java.lang.String	getID() Returns an service ID.
private java.lang.String	getVersion() Returns the agents version.
private void	handleRegistryMessage() Handle incoming JsonRARegistryMessage messages which indicates that an agent would like to register or unregister itself to/from the system.
private void	init() Open all required ActiveMQ connections.
boolean	isActive() Determines whether the method StopableObject.shutDown() has been called on this object or not.
void	run() Starts the Registry service.
private void	sendInitialRegistryRequest() Sends an initial JsonRARegistryRequest message to invite all active agents.
void	shutDown() Shuts the object down.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, clone, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Field Detail

shutDown

private boolean shutDown

Determines whether the method shutDown() has been called or not.

requestRegistryTopic

private de.hawhamburg.livingplace.messaging.activemq.wrapper.LPPublisher requestRegistryTopic

Publisher for register requests.

registryTopic

private de.hawhamburg.livingplace.messaging.activemq.wrapper.LPSubscriber registryTopic

Listener for register messages.

rand

private java.util.Random rand

A central random object.

systemAgent

private ReachabilityWorker systemAgent

The worker which called this property service.

Constructor Detail

Registry

public Registry()

Initializes a new Registry object.

Registry

public Registry(ReachabilityWorker worker)

Initializes a new Registry object with an ReachabilityWorker.

Parameters:

worker - The ReachabilityWorker which started this registry service.

Method Detail

isActive

public final boolean isActive()

Description copied from interface: StopableObject

Determines whether the method StopableObject.shutDown() has been called on this object or not.

Specified by:

isActive in interface StopableObject

Returns:

true if shutDown() wasn't called, otherwise true.

See Also:

StopableObject.isActive()

shutDown

public final void shutDown()

Description copied from interface: StopableObject

Shuts the object down. The method shall ensure, that all opened or started resources (e.g. ActiveMQ connections, started threads) will be controlled shut down before the objects ends itself.

Specified by:

shutDown in interface StopableObject

See Also:

StopableObject.isActive()

run

public final void run()

Starts the Registry service. Initially it sends a registry request and handles registry messages afterwards, until the shutDown() method has been called.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

init

private void init()

Open all required ActiveMQ connections.

sendInitialRegistryRequest

private void sendInitialRegistryRequest()

Sends an initial JsonRARegistryRequest message to invite all active agents.

handleRegistryMessage

private void handleRegistryMessage()

Handle incoming JsonRARegistryMessage messages which indicates that an agent would like to register or unregister itself to/from the system.

end

private void end()

Gracefully ends the system by disconnecting all open ActiveMQ connections.

getID

private java.lang.String getID()

Returns an service ID.

Returns:

The service ID containing the ProjectInfo.REACHABILITY_AGENT_WORKER_NAME, the services name and a pseudo random number.

getVersion

private java.lang.String getVersion()

Returns the agents version.

Returns:

The agents version as ProjectInfo.REACHABILITY_AGENT_VERSION.