public void forceDisconnect(){ //just disconnect, sending no messages
        System.out.println("Client disconnected forcibly");
        send("You have been disconnected forcibly.");
        this.user = null; //causes the thread to stop
        try{
            this.socket.close();
            this.in.close();
            this.out.close();
        } catch (Exception e) { System.out.println("Caught non-problematic exception: "+e); }
    }