File transfer and threading.

In fact having read the documentation again, i think waht i need is amd... but i'm worry about don't getting the right meaning for each term (amd, ami).

What i need is a responsible GUI while i transfer file from my servlet, and i need to be able to respond to other method calls while transfering the file too.

My application scheme is like this:

module Q4MusicServer
{
    sequence <Q4MusicClient::Mp3Client*> ClientList;
    
    interface Mp3Server
    {
        // Add a client to the queue
	idempotent void RegisterClient(Q4MusicClient::Mp3Client* c, out bool bSuccess);
	    
	// Remove a client from the queue
	idempotent void UnregisterClient(Q4MusicClient::Mp3Client* c);
        
        // Send a message to a client.
        nonmutating SendMessage(string message);
	};
};

This "music server" is on the only machine that have speakers on my office, so a number of clients is going to register to this server to request his music is played. The server register all clients and then, one by one, request the files from every client. The client interface is like is:

module Q4MusicClient
{
    sequence<byte> ByteSeq;
    
	interface Mp3Client
	{
            nonmutating bool HasFile(string fileName);
        
	    ["ami"] nonmutating ByteSeq getFile(string path, int pos, int num);
        
            // Gets the name of the mp3 that the client want to play
            nonmutating string GetCurrentMp3Name();

            nonmutating SendMessage(string message);
       
            // if the server is shut-down, first it tries to disconnect the clients
            idempotent void Disconnect();
	};
};

In my server the mp3 player runs on his own thread, and i can set a callback to the mp3 filereader, so i'm not concerned about blocking on the server. The file read callback, in fact, should wait the response of the client method getFile, similar to what happen when you read a file from the disk

In the client, in the other side, i need to procces the response to the getFile and, maybe, at the same time, respond to other methods (like server sending me a message using SendMessage), and i need to keep the GUI responsive too. For this reasons, i think i should use AMD on the Mp3Client instead of AMI. What do you think???

Thank you very much!