Internet Accesses Freeze Java Application

I have been programming a Java application, which is actually an instant text messaging system, that obviously makes internet accesses.
The thing is, I have got this JFrame, with JScrollPanes, JTextAreas for messaging, and whenever the user presses the magical 'send' button; till the reply comes, the window freezes; you know it turns into grey.
The way I send the messages is just to call the method that makes the connections and writes the data.
How should I modify my code that my application should not freeze while waiting response? Is there a way to decrease the priority of a method or something?
Thanks in advance..

To clarify a bit.
When you press the button an event is generated and put into the
event handling queue (which handles all awt/swing events such as redraws/resizes etc). The Queue is processed by the event processing
thread which pulls the button pressed event from the queue, finds
the associated eventHandlers and calls them. What this means is that
any code inside your event handler is run in the Event handling thread
which causes it to not be able to handle any more events until the
code in your handler is finished. Therefore all refreshes/button presses
/resizes etc. (everything to do with the GUI and some other bits too)
stop responding until your handler returns. Creating network connections
can take a fair bit of time which means your handler takes a fair amount
of time which means that the GUI locks up for a fair amount of time.
Right, that there is the reason your GUI stalls.
now, as pkwooster said, the way around this is to create a seperate
thread that handles your connections to the internet. At the simplest
level this thread can be created inside your "button pressed" event handler
. For more complex solutions you will need to find someway of notifying
a running thread that you have more work for it.
pkwooster also said that there is a lot of code in this forum on topics
related to the task you are attempting. You might wish to take his
advice and look for it.
matfud

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