GUI freeze after click on button

Question

I\'m trying to create a client/server application. The problem is the confirm button on client side works for the first time input but if I hit the same button for the anoth

Answer 1

When you click on a button, the actionPerformed method of your ActionListener is triggered on the Event Dispatch Thread. This thread is the one-and-only thread responsible for the UI.

The UI will remain frozen until you leave the actionPerformed method (as the thread is occupied). So if your ActionListener blocks (e.g. with your fromServer.readLine() call), the UI will remain frozen until that blocking call is ended.

That is why the general guideline is to offload long tasks to a worker thread. The Swing concurrency tutorial contains more information.