You can send any object as a parameter, so you could just send the
JTextArea itself, if you wanted to. That being said, if you want to send its
contents, rather than the JTextArea itself, I suggest you look at the
JTextArea.getDocument() method.

   - Oliver

If its just plain text without any formatting then use getText() and send
the string to the receiver.
However if you need to preserve formatting it can get tricky. Read the API
for the JTextArea and JTextComponent.