gistfile1.clj

; http://stackoverflow.com/questions/3651494/jfilechooser-with-confirmation-dialog
; in Clojure

(defn chooser []
  (proxy [javax.swing.JFileChooser] []
    (approveSelection []
      (let [f (proxy-super getSelectedFile)]
        (if (and (.exists f)
                 (= (.getDialogType this)
                    javax.swing.JFileChooser/SAVE_DIALOG))
          (do
            (let [result (javax.swing.JOptionPane/showConfirmDialog
                          this "The file exists, overwrite?" "Existing file"
                          javax.swing.JOptionPane/YES_NO_CANCEL_OPTION)]
              (condp = result
                javax.swing.JOptionPane/YES_OPTION (proxy-super approveSelection)
                javax.swing.JOptionPane/NO_OPTION     nil
                javax.swing.JOptionPane/CLOSED_OPTION nil
                javax.swing.JOptionPane/CANCEL_OPTION (.cancelSelection this)
                nil)))
          (proxy-super approveSelection))
        ))))

(.showOpenDialog (chooser) nil)
(.showSaveDialog (chooser) nil)

(let [c (chooser)]
  (if (== (.showSaveDialog c nil) 0)
    (.getSelectedFile c))
  )