Java Chat Server

Answer 1

Your first problem is with the parsing of the message from the user.

You loop through the string, and it has one of two options, either the character is a dash or it is invalid.

So, ideally, you should be getting an invalid message for the number of a characters in the username before the dash.

You should use String.indexOf to determine where the dash is, and then split the message into it's two parts, and if the result of indexOf is -1 then it is an invalid message.

Answer 2

So far I found this to be a problem, but I don't think this is the only problem..

This will help the NoSuchElementException On around line 90 Change this...

while( (s=fromClient.nextLine().trim()) != null )
{

to this...

while(fromClient.hasNext())
{
   s = fromClient.nextLine().trim();

OK just found another problem in ClientToThread.run()... You are closing the client connections after you send the first message. I commented them both out and it seems to be working a little better.

public void run()
  {
     toClient.println(mesg);
     try {
        //toClient.close();
        //client.close();
     }
     catch (Exception e)  {
        e.printStackTrace();
     }
  }