向多个客户端广播对象

Question

Currently I try to implement a Server/Client - Application and came up with a problem, I cant find a solution for.

Im running a Server , which is waiting for Clients to login, adding them to a cachedThreadPool and starting a new Runnable for each Client , to handle their individual requests etc.

Now there are some answers to these requests, which have to be broadcasted after the server did his processing.

        this.mOos = new ObjectOutputStream(this.mSocket.getOutputStream());
        this.mOos.flush();
        this.mOis = new ObjectInputStream(this.mSocket.getInputStream());

        while(true)
        {
            Object o = this.mOis.readObject();

            if(o !=null && this.mInputList.size() < 20)
            {
                this.mInputList.add(o);
            }

            if(!this.mInputList.isEmpty())
            {
                handleIncomingObject();
            }

            if(!this.mOutputList.isEmpty())
            {                       
                try 
                {
                    this.mOos.writeObject(this.mOutputList.remove(0));
                    this.mOos.flush();
                    this.mOos.reset();
                } 
                catch (IOException e) 
                {
                    e.printStackTrace();
                }
            }               
        }

Now what I'm having trouble with is, that when I process a request in:

handleIncomingObject();

which needs to be broadcasted.

My approach is to give a reference to the ExecutorService Object, when I create the runnable, to have access to the threadpool IN the different threads.

As you may see, every client got his own

LinkedList<Object> mInputList
LinkedList<Object> mOutputList

to buffer incoming and outgoing messages.

In handleIncomingObject() I'd like to do something like:

//assume exec as ExecutorService
for(Thread t : exec)
{
        mOutputList.add(new Message(message));
}

Thanks in advance any every help or suggestions.

Greetings, Ben.

Answer 1

Use a Vector containing all clients and iterate over this Vector to send broadcast messages. You can use a method like:

public static synchronized void broadcast(Message msg) {
    for(Client c : vector) {
        c.mOutputList.add(msg);
    }
}