context.arch.comm.clients
Class ClientsPool

java.lang.Object
  java.lang.Thread
      context.arch.comm.clients.ClientsPool

All Implemented Interfaces:

java.lang.Runnable

Direct Known Subclasses:

Client

public class ClientsPool

extends java.lang.Thread

This class defines a pool of threads that can handle a communication. When a BaseObject wants to send an asynchronous message to another CTK object, it creates the RequestObject, added it to a IndependentCommunication object, which is the parameter of the BaseObject.independentUserRequest() call. This IndependentCommunication is added to a synchronized FIFO vector (SynchFIFO object) from which the ClientsPool get the request to send. Then, as soon as a IndependentCommunication is added to the SynchFIFO, the ClientsPool object removes it to give it to a thread (Client object) from the pool. When a Client object is asked to handle an IndependentCommunication, it is also removed from the pool. The Client object sends the request to the given CTK object, and get the reply and the exceptions. In order for the BaseObject to get the reply, the IndependentCommunication contains also 2 useful attributes : the DataObject reply and the Vector exceptions. Then the Client object adds the reply to the same object it gets as well as the exception it could have caught. After updating the IndependentCommunication object, the Client calls the BaseObject handleIndependentReply method with the parameter an object containing the same IndependentCommunication object. At the end of the communication, the IndependentCommunication object contains the original request, the reply (if any) and the exceptions that occured (if any); and is sent back to the BaseObject, that does nothing by default. If a widget or server or interpreter wants to handle the reply, it overrides the BaseObject handleIndependentReply method, and may check the reply for each request it has sent. In order to group a bunch of requests (for example, a widget sends many PINGs to its subscribers) we define a IndependentCommunications object to help handling the replies. Before sending the requests, the widget creates an IndependentCommunications object in which all IndependentCommunication objects will be added by the Client thread at the end of the communication. The IndependentCommunications object is specified while calling the BaseObject independentUserRequest. If it is null, the Client thread will create a new one, add the IndependentCommunication object in it, and send it to the BaseObject handleIndependentReply method.

Author:

Agathe

See Also:

Client, SynchFIFO

Field Summary

static int	clientsNumber The number of authorized clients
CommunicationsObject	comm The Communications object
static boolean	DEBUG Debug flag
static int	DEFAULT_CLIENTS_NUMBER The default number of clients
protected SynchFIFO	fifo This FIFO object contains the IndependentCommunication object that contain the RequestObject to send
protected static SynchFIFO	threads The synchronized vector of threads

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

ClientsPool()
Creates a new empty ClientsPool.

ClientsPool(CommunicationsObject commObject)
Creates a ClientsPool with the default number of threads in the pool of threads.

ClientsPool(int numberOfClients, CommunicationsObject commObject)
Creates a generic ClientsPool.

Method Summary

void	addRequest(IndependentCommunication request) This method is called to add an IndependentCommunication object containing the RequestObject to send, to the fifo object.
void	run() The run method called to start the thread.
void	stopAllIdleClients()

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getContextClassLoader, getName, getPriority, getThreadGroup, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setName, setPriority, 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

DEBUG

public static boolean DEBUG

Debug flag

threads

protected static SynchFIFO threads

The synchronized vector of threads

clientsNumber

public static int clientsNumber

The number of authorized clients

DEFAULT_CLIENTS_NUMBER

public static int DEFAULT_CLIENTS_NUMBER

The default number of clients

comm

public CommunicationsObject comm

The Communications object

fifo

protected SynchFIFO fifo

This FIFO object contains the IndependentCommunication object that contain the RequestObject to send

Constructor Detail

ClientsPool

public ClientsPool(int numberOfClients,
                   CommunicationsObject commObject)

Creates a generic ClientsPool. It creates the pool of numberOfClients threads.

Parameters:

numberOfClients - The number of available clients in the pool

ClientsPool

public ClientsPool(CommunicationsObject commObject)

Creates a ClientsPool with the default number of threads in the pool of threads.

ClientsPool

public ClientsPool()

Creates a new empty ClientsPool.

Method Detail

run

public void run()

The run method called to start the thread. The ClientsPool waits for a new IndependentCommunication object in the fifo object. As soon as a new one is added, the ClientsPool waits for the next available Client to handle the request.

See Also:

SynchFIFO, Client

addRequest

public void addRequest(IndependentCommunication request)

This method is called to add an IndependentCommunication object containing the RequestObject to send, to the fifo object.

Parameters:

request - The IndependentCommunication object containing the RequestObject

See Also:

SynchFIFO

stopAllIdleClients

public void stopAllIdleClients()