This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
if the original window (JFrame ) is DataApplication, it won't work the way you're trying it.
1) the new window should be a JDialog - very rare to have 2 JFrames running around.
2) in the constructor of the dialog, pass a reference of the DataApplication instance to the dialog
3) set the various label texts to those from the instance passed