org.objectweb.jonas.discovery
Class DiscoveryGreetingResponder

java.lang.Object
  org.objectweb.jonas.discovery.DiscoveryComm
      org.objectweb.jonas.discovery.DiscoveryGreetingResponder

All Implemented Interfaces:

java.lang.Runnable

Direct Known Subclasses:

DiscoveryGreetingListener

public class DiscoveryGreetingResponder
extends DiscoveryComm

This class sends a multicast message stating the servername and the port at which it will listen for messages. It listens at the unicast port for a pre-determined time (greetingTimeOut) and if it receives a message indicating that a server with the same ID already exists in the domain then it terminates the discovery service.

Version:

1.0

Author:

Vivek Lakshmanan

Field Summary

protected int	greetingPort Port to listen to for greeting responses.
protected int	greetingTimeOut Time out period to listen to greetingPort for replies.
protected java.net.DatagramSocket	recvUnicastSocket Used to recieve responses to the initial greeting message sent out on the multicast port.

Fields inherited from class org.objectweb.jonas.discovery.DiscoveryComm

domainName, jonasName, multicastSocket, notStopped, RECEIVE_BUFFER_SIZE, serverId, unicastSocket, urls

Constructor Summary

DiscoveryGreetingResponder(DiscoveryManager dm)
Constructs a DiscoveryGreetingResponder associated to the DiscoveryManager

Method Summary

protected DiscGreeting	createDiscGreeting(boolean startup) Create a discovery greeting message
void	handleGreeting() Creates a new thread to send the greeting message and listens for rejection messages in response.
void	run()
void	stop() Throw the run time exception to state that a server with the same name already exists.

Methods inherited from class org.objectweb.jonas.discovery.DiscoveryComm

createNotifMessage, getDatagram, getServerId, join, sendNotif, sendResponse, setDomainName, setJonasName, setServerId, setUrls

Methods inherited from class java.lang.Object

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

Field Detail

recvUnicastSocket

protected java.net.DatagramSocket recvUnicastSocket

Used to recieve responses to the initial greeting message sent out on the multicast port.

greetingPort

protected int greetingPort

Port to listen to for greeting responses.

greetingTimeOut

protected int greetingTimeOut

Time out period to listen to greetingPort for replies.

Constructor Detail

DiscoveryGreetingResponder

public DiscoveryGreetingResponder(DiscoveryManager dm)

Constructs a DiscoveryGreetingResponder associated to the DiscoveryManager

Parameters:

dm - DiscoveryManager to which this instance is associated

Method Detail

createDiscGreeting

protected DiscGreeting createDiscGreeting(boolean startup)

Create a discovery greeting message

Parameters:

startup - - true: means that is a greeting message at the point of start up of the discovery service. false: means this is a reply to a previous greeting message.

Returns:

a Discovery Greeting message.

run

public void run()

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class DiscoveryComm

See Also:

Runnable.run()

handleGreeting

public void handleGreeting()
                    throws DuplicateServerNameException

Creates a new thread to send the greeting message and listens for rejection messages in response.

Throws:

DuplicateServerNameException - - If a server with the same ID is found in the domain.

stop

public void stop()

Throw the run time exception to state that a server with the same name already exists.

Overrides:

stop in class DiscoveryComm