class ClientImplementation extends NetworkPeer implements Client, Runnable {
    int id; 
    synchronized public void setID(Integer index) {
	this.id = index.intValue(); 
    }
    Client[] peer = new Client[100]; 
    int index = -1; 
    synchronized public void register(Integer index, Client client) {
	this.index = index.intValue(); 
	this.peer[this.index] = client; 
    }
    Boolean available = new Boolean(true); 
    synchronized public void setAvailable(Boolean availability) {
	this.available = availability; 
    }
    int balance; 
    public int getBalance() {
	return this.balance; 
    }
    String name; 
    public String report() {
	return this.name + ": " + this.balance; 
    }
    public ClientImplementation(String name) {
	this.name = name; 
    }
    public void startAsClientOf(java.rmi.Remote peer) throws java.rmi.RemoteException {
	Server server = (Server)peer;
	server.register(this); 
	this.server = server; 
	new Thread(this).start(); 
    }
    Server server; 
    public void run() {
        while (true) {
	    try {
		Thread.sleep((int) Math.random() * 1000 + 1000); 
		if (this.available.booleanValue())
		    this.initiateTransfer(); 
	    } catch (Exception e) { } 
	}
    }
    synchronized private void initiateTransfer() throws java.rmi.RemoteException {
	if (this.index > 0) {
	    int chosen = (int) (Math.random() * (this.index + 1)); 
	    if (chosen == this.id // always deal with someone else
                || peer[chosen] == null) return; 
            System.out.println(this.id + " chooses " + chosen); 
            this.balance += peer[chosen].process(
			                   new Transaction(
					     this.name, 
					     this.id, 
					     (int)(Math.random() * 10 + 1), 
					     Math.random() > 0.5 ? "sent" 
					                         : "requested"));
	}
    }
    synchronized public int process(Transaction transaction) throws java.rmi.RemoteException {
	if (this.available.booleanValue()) {

	    this.balance = transaction.update(this);

	    if (transaction.direction.equals("sent")) {
                return - (transaction.amount); 
	    } else {
		return (transaction.amount); 
	    }

	} else return 0; // object unavailable: method idempotent 
    }
    public static void main(String[] args) throws Exception {
        String
	    ownName = args[0],
	    serverHostName = args[1], 
	    serverPortNumber = args[2], 
	    serverName = args[3];

	ClientImplementation client = new ClientImplementation(ownName); 
	client.startAsNetworkClientOf(serverHostName, 
				      Integer.parseInt(serverPortNumber), 
				      serverName); 
    }
    public void startAsLocalServer() {
	// not needed, a client is an anonymous figure, a guest without a permanent address ...
    }
}