org.kaariboga.core
Class KaaribogaBase

java.lang.Object
  |
  +--org.kaariboga.core.KaaribogaBase

All Implemented Interfaces:

java.util.EventListener, KaaribogaListener, KaaribogaMessageListener, java.io.Serializable

public class KaaribogaBase

extends java.lang.Object

implements java.io.Serializable, KaaribogaListener, KaaribogaMessageListener

A class to host mobile agents called kaaribogas. It is able to dispatch and receive kaaribogas, handle their requests and messages.

See Also:

Serialized Form

Inner Class Summary

(package private) class	KaaribogaBase.ListenThread Listens on the specified port and spawns new threads to receive incoming agents.
(package private) class	KaaribogaBase.ReceiveMessageThread Handles a messages incoming through a socket connection.
protected class	KaaribogaBase.SendMessageThread Sends a KaaribogaMessage to another base.

Field Summary

private KaaribogaAddress	baseAddress The KaaribogaAddress of this base
private java.util.Vector	baseListeners Classes that listen to the fired base events.
private KaaribogaAddress	boServer Base online server that registers all servers in this domain.
(package private) java.util.Hashtable	boxes Stores all agents and related information.
protected ClassManager	classManager Handles classes and their byte codes.
private long	counter Used to generate a unique name for a kaariboga.
(package private) long	delay Delay time in milliseconds after which an anused agent class is removed from memory.
private KaaribogaAddress	ipServer Server that serves dynamic IP addresses
private boolean	isOnline Is this server on- or offline?
private KaaribogaBase.ListenThread	listenThread Thread that accepts network connections.
private java.util.HashMap	messageHandlers Message handlers that have registered on this base to handle certain kinds of messages.
private java.lang.Object	parent The object that created this base.
private int	port The port number on which the server listens.
(package private) java.net.ServerSocket	serverSocket Listens on the main port.
private java.util.HashMap	services The base can be extended by services, that are provided by plug-ins.
int	version Not used.

Constructor Summary

KaaribogaBase(java.lang.Object parent, ClassManager clManager)
Creats a new Kaariboga Base.

Method Summary

void	addBaseListener(BaseListener l) Adds a base event listener.
void	addKaaribogaOnArrival(Kaariboga kaariboga, java.net.InetAddress sender) Adds a kaariboga to the base and starts it's thread.
void	addKaaribogaOnCreation(Kaariboga kaariboga, java.net.InetAddress sender) Adds a kaariboga to the base, performs some initialisation and starts it's thread.
boolean	addMessageHandler(KbMessageHandler handler, java.lang.String kind) Adds a message handler for a specified kind of message to this base.
boolean	addService(KbPlugIn plugIn, java.lang.String name) Adds a service to this base.
void	destroyKaariboga(java.lang.Object sender, java.lang.String name) Destroys a kaariboga agent with all necessary clean up.
protected void	dispatch(Kaariboga kaariboga, KaaribogaAddress address) Dispatches a kaariboga to another base.
void	dispatchKaariboga(java.lang.Object sender, java.lang.String name, KaaribogaAddress destination) Dispatches a kaariboga agent with all necessary clean up.
void	dispose() Shuts down the network connection.
protected void	fireKaaribogaArrived(java.lang.String name) Fires an event if a new kaariboga has arrived.
protected void	fireKaaribogaCreated(java.lang.String name) Fires an event if a new kaariboga was created.
protected void	fireKaaribogaDestroyed(java.lang.String name) Fires an event if a kaariboga has been destroyed.
protected void	fireKaaribogaLeft(java.lang.String name) Fires an event if a kaariboga was dispatched to another base.
java.lang.String	generateName() Generates a unique name that can be used to initialize agents.
KaaribogaAddress	getBaseAddress(java.lang.Object sender) Returns the KaaribogaAddress of this base.
java.util.Enumeration	getKaaribogaNames(java.lang.Object sender) Gets the names of all kaariboga agents on this base.
boolean	getOnlineStatus() Determines if the server is online.
java.lang.String[]	getServiceNames(java.lang.Object sender) Returns the names of all the services currently available.
java.lang.Object	getServiceObject(java.lang.Object sender, java.lang.String name) Returns a service object for a specified service name.
void	goOffline(java.lang.Object sender) Performs all neccessary actions to go offline
void	goOnline(java.lang.Object sender, int portNo, KaaribogaAddress boServer, KaaribogaAddress ipServer) Performs all neccessary actions to go online
void	goOnlineForDynamicIP(java.lang.Object sender) If the server has no static IP address this method is called to determine the dynamic IP address.
void	handleMessage(KaaribogaMessage msg) Handles incoming messages from other bases and kaaribogas.
void	kaaribogaDestroyRequest(KaaribogaEvent e) Handles the destroy request of a kaariboga.
void	kaaribogaDispatchRequest(KaaribogaEvent e) Handles the dispatch request of a kaariboga.
void	kaaribogaMessage(KaaribogaMessageEvent e) Handles messages that are fired by kaaribogas.
void	kaaribogaSleepRequest(KaaribogaEvent e) Handles the sleep request of a kaariboga.
void	removeBaseListener(BaseListener l) Removes a base event listener.
boolean	removeMessageHandler(KbMessageHandler handler, java.lang.String kind) Removes a message handler for a specified kind of message to this base.
boolean	removeService(KbPlugIn plugIn, java.lang.String name) Removes the service named name from this base.

Methods inherited from class java.lang.Object

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

Field Detail

version

public final int version

Not used.

isOnline

private boolean isOnline

Is this server on- or offline? Use GetOnlineStatus to retrieve this value.

parent

private java.lang.Object parent

The object that created this base. This variable is used for security purposes. The parent has more rights than other objects.

messageHandlers

private java.util.HashMap messageHandlers

Message handlers that have registered on this base to handle certain kinds of messages.

services

private java.util.HashMap services

The base can be extended by services, that are provided by plug-ins.

boServer

private KaaribogaAddress boServer

Base online server that registers all servers in this domain.

ipServer

private KaaribogaAddress ipServer

Server that serves dynamic IP addresses

baseListeners

private java.util.Vector baseListeners

Classes that listen to the fired base events.

delay

long delay

Delay time in milliseconds after which an anused agent class is removed from memory.

port

private int port

The port number on which the server listens.

baseAddress

private KaaribogaAddress baseAddress

The KaaribogaAddress of this base

counter

private long counter

Used to generate a unique name for a kaariboga.

listenThread

private volatile KaaribogaBase.ListenThread listenThread

Thread that accepts network connections.

classManager

protected ClassManager classManager

Handles classes and their byte codes.

boxes

java.util.Hashtable boxes

Stores all agents and related information.

serverSocket

java.net.ServerSocket serverSocket

Listens on the main port.

Constructor Detail

KaaribogaBase

public KaaribogaBase(java.lang.Object parent,
                     ClassManager clManager)

Creats a new Kaariboga Base.

Parameters:

clManager - The ClassManager to use.

Method Detail

handleMessage

public void handleMessage(KaaribogaMessage msg)

Handles incoming messages from other bases and kaaribogas. At this time the function just prints out the message contents.

dispatch

protected void dispatch(Kaariboga kaariboga,
                        KaaribogaAddress address)

Dispatches a kaariboga to another base. It stops the kaariboga, spawns a new thread to send it to another base and removes it from the current base.

Parameters:

kaariboga - The agent that has to be dispatched.

address - Address of the destination.

dispose

public void dispose()

Shuts down the network connection.

addKaaribogaOnArrival

public void addKaaribogaOnArrival(Kaariboga kaariboga,
                                  java.net.InetAddress sender)

Adds a kaariboga to the base and starts it's thread. This method should be called to add an arriving Kaariboga agent to the base.

addKaaribogaOnCreation

public void addKaaribogaOnCreation(Kaariboga kaariboga,
                                   java.net.InetAddress sender)

Adds a kaariboga to the base, performs some initialisation and starts it's thread. This method should be called to add a newly created Kaariboga agent to the base.

kaaribogaDispatchRequest

public void kaaribogaDispatchRequest(KaaribogaEvent e)

Handles the dispatch request of a kaariboga.

Specified by:

kaaribogaDispatchRequest in interface KaaribogaListener

kaaribogaSleepRequest

public void kaaribogaSleepRequest(KaaribogaEvent e)

Handles the sleep request of a kaariboga.

Specified by:

kaaribogaSleepRequest in interface KaaribogaListener

kaaribogaDestroyRequest

public void kaaribogaDestroyRequest(KaaribogaEvent e)

Handles the destroy request of a kaariboga.

Specified by:

kaaribogaDestroyRequest in interface KaaribogaListener

getKaaribogaNames

public java.util.Enumeration getKaaribogaNames(java.lang.Object sender)

Gets the names of all kaariboga agents on this base.

Parameters:

sender - The object that sends the request.

generateName

public java.lang.String generateName()

Generates a unique name that can be used to initialize agents.

getBaseAddress

public KaaribogaAddress getBaseAddress(java.lang.Object sender)

Returns the KaaribogaAddress of this base.

Parameters:

sender - The object that requests the address.

goOnlineForDynamicIP

public void goOnlineForDynamicIP(java.lang.Object sender)
                          throws java.net.UnknownHostException,
                                 java.io.IOException,
                                 java.lang.InterruptedException

If the server has no static IP address this method is called to determine the dynamic IP address.

Parameters:

sender - The object that calls this method

goOnline

public void goOnline(java.lang.Object sender,
                     int portNo,
                     KaaribogaAddress boServer,
                     KaaribogaAddress ipServer)

Performs all neccessary actions to go online

Parameters:

sender - The object that calls this method. Only the parent of this class may call this method, agents are not allowed to do this.

portNo - The port on which the server should listen

boServer - The domain server, if there is one. May be null.

ipServer - The server that determines this host's IP address if dynamic IP addresses are used

goOffline

public void goOffline(java.lang.Object sender)

Performs all neccessary actions to go offline

Parameters:

sender - The object that calls this method. Only the parent of this class may call this method, agents are not allowed to do this. XXX This method performs no check for the threads that are still running

getOnlineStatus

public boolean getOnlineStatus()

Determines if the server is online. An agent could check the online state before it tries to travel to another server.

destroyKaariboga

public void destroyKaariboga(java.lang.Object sender,
                             java.lang.String name)

Destroys a kaariboga agent with all necessary clean up.

Parameters:

sender - Object that calls this method.

name - Name of the kaariboga agent.

dispatchKaariboga

public void dispatchKaariboga(java.lang.Object sender,
                              java.lang.String name,
                              KaaribogaAddress destination)

Dispatches a kaariboga agent with all necessary clean up.

Parameters:

sender - Object that calls this method.

name - Name of the kaariboga agent.

destination - Where to send the kaariboga.

addBaseListener

public void addBaseListener(BaseListener l)

Adds a base event listener.

removeBaseListener

public void removeBaseListener(BaseListener l)

Removes a base event listener.

fireKaaribogaCreated

protected void fireKaaribogaCreated(java.lang.String name)

Fires an event if a new kaariboga was created.

Parameters:

name - Name of the kaariboga agent.

fireKaaribogaArrived

protected void fireKaaribogaArrived(java.lang.String name)

Fires an event if a new kaariboga has arrived.

Parameters:

name - Name of the kaariboga agent.

fireKaaribogaDestroyed

protected void fireKaaribogaDestroyed(java.lang.String name)

Fires an event if a kaariboga has been destroyed.

Parameters:

name - Name of the kaariboga agent.

fireKaaribogaLeft

protected void fireKaaribogaLeft(java.lang.String name)

Fires an event if a kaariboga was dispatched to another base.

Parameters:

name - Name of the kaariboga agent.

kaaribogaMessage

public void kaaribogaMessage(KaaribogaMessageEvent e)

Handles messages that are fired by kaaribogas.

Specified by:

kaaribogaMessage in interface KaaribogaMessageListener

addMessageHandler

public boolean addMessageHandler(KbMessageHandler handler,
                                 java.lang.String kind)

Adds a message handler for a specified kind of message to this base. The ability of a base to handle messages may be extended by different message handlers. There may be more than one message handler for one kind of message.

Parameters:

handler - The message handler, that wants to receive the specified kind of message

kind - The kind of message, that should be delivered to the message handler

Returns:

True, if successfull

See Also:

KaaribogaMessage

removeMessageHandler

public boolean removeMessageHandler(KbMessageHandler handler,
                                    java.lang.String kind)

Removes a message handler for a specified kind of message to this base. The message handler must be the same as the one that registered for this kind of message.

Parameters:

handler - The message handler, that wants to receive the specified kind of message

kind - The kind of message, that should be delivered to the message handler

Returns:

True if successfull

See Also:

KaaribogaMessage

addService

public boolean addService(KbPlugIn plugIn,
                          java.lang.String name)

Adds a service to this base. A plug-in may provide different services. Agents may use the service name to get access to a service object.

Parameters:

plugIn - The plugIn that provides the service

name - Name of the service

removeService

public boolean removeService(KbPlugIn plugIn,
                             java.lang.String name)

Removes the service named name from this base. + The service can only be removed by the plug-in that provided it. A plug-in may provide more than one services. So this method does not neccessary remove the plug-in.

Parameters:

plugIn - The plugIn that provides the service

name - Name of the service

getServiceNames

public java.lang.String[] getServiceNames(java.lang.Object sender)

Returns the names of all the services currently available. A service is provides by a plug-in.

Parameters:

sender - The object that calls this method.

Returns:

Names of the available services.

getServiceObject

public java.lang.Object getServiceObject(java.lang.Object sender,
                                         java.lang.String name)

Returns a service object for a specified service name. The caller of this method must make shure, that the returned object is of the expected type.

Parameters:

sender - The object that calls this method.

name - Name of the requested service

Returns:

An object that implements the requested Service, null if the object is not available or the sender is not allowed to request the object.