working on selected jInternalFrame by a function on toolbar..

Hi,

i'm writing an image editing application. i can open many documents
with new JInternalFrames.. i wrote a new class for JInternalFrames. And
I have a toolbar. i wrote this toolbar into ToolBar.java and adding to
application frame.. When i push the button on it, i want to do that
process on selected JInternalFrame. How can i know which JInternalFrame
is selected ?

Thanks in advance..

Regards,
Atila Gunes

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