Getting started

I'm not sure if this is the right place to put this but I need some help, I need to make a midi message mapper but i'm stuck on certain section, I was wondering if you could help!

Below are the bits i'm stuck on. I need ....

The application to present a list of MIDI input devices to the user.
The user shall select the appropriate input device and press OK or Cancel.
If the user presses Cancel, then the application shall exit cleanly.

What sort of code would do this?

help would really get me started! thanks

Code :

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public class MIDIMapper extends JFrame {
   public MIDIMapper(){}
 
   public void createAndShowGUI(){
        // Add GUI
   }
 
   public static void main(String[] args){
       javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new MIDIMapper().createAndShowGUI();
            }
        });
   }
}

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