service.id
Class IdentificationServer

java.lang.Object
  java.lang.Thread
      service.id.IdentificationServer

All Implemented Interfaces:

java.lang.Runnable

public class IdentificationServer
extends java.lang.Thread

The identification server has to started before launching any process. Its goal is to set the identifiers of the processes of the system and to make them knowing the identifiers of all the processes.

The server communicates with the processes in two ways, depending on the communication direction:

• UDP multicast, from process to server: to be able to launch the server on any machine without requiring for a process to know the localisation of the server, multicast communication is used. The IP/port of the multicast group is set in the service.IIdentification interface. Moreover, as the communication element of a process can loose messages and considering that the communication with the identification server must be reliable, a process sends messages to the server only through UDP multicast.
• Communication element, from server to process: a reliable communication element without additionnal errors is used to communicate with the processes.

Nested Class Summary

protected class

IdentificationServer.PingManager The heartbreak thread send regularly an hearbreak message to each process.

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

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

Field Summary

protected CommunicationElement	commElt The communication element used for sending data to processes
protected java.net.InetAddress	group The multicast IP group address
protected java.util.Vector<ProcessIdentifier>	identifiers Set of all the process identifiers of the system
protected int	lastId The last identifier used.
protected java.net.MulticastSocket	socket The UDP multicast socket that is used by a process to contact the identification server

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

IdentificationServer()

Method Summary

java.util.Vector<ProcessIdentifier>	getIdentifiers()
protected void	initialize() Initialize the server by creating its multicast socket.
static void	main(java.lang.String[] argv)
protected void	printIdentifiers() Print on standard output all process identifiers.
protected IdentificationData	receiveData() Wait for a data received on the UDP multicast group.
void	run()
protected void	sendAllId() Send all process identifiers to each process.
void	setIdentifiers(java.util.Vector<ProcessIdentifier> identifiers)

Methods inherited from class java.lang.Thread

activeCount, checkAccess, 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

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

Field Detail

identifiers

protected java.util.Vector<ProcessIdentifier> identifiers

Set of all the process identifiers of the system

lastId

protected int lastId

The last identifier used. Allow a unique identifier management.

commElt

protected CommunicationElement commElt

The communication element used for sending data to processes

socket

protected java.net.MulticastSocket socket

The UDP multicast socket that is used by a process to contact the identification server

group

protected java.net.InetAddress group

The multicast IP group address

Constructor Detail

IdentificationServer

public IdentificationServer()
                     throws CommunicationException

Throws:

CommunicationException

Method Detail

getIdentifiers

public java.util.Vector<ProcessIdentifier> getIdentifiers()

Returns:

the set of process identifiers

setIdentifiers

public void setIdentifiers(java.util.Vector<ProcessIdentifier> identifiers)

Parameters:

identifiers - set the process identifier set

printIdentifiers

protected void printIdentifiers()

Print on standard output all process identifiers.

sendAllId

protected void sendAllId()

Send all process identifiers to each process.

receiveData

protected IdentificationData receiveData()

Wait for a data received on the UDP multicast group.

Returns:

the received data, null in case of problem

initialize

protected void initialize()

Initialize the server by creating its multicast socket.

run

public void run()

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

main

public static void main(java.lang.String[] argv)