gistfile1.clj

(ns org.drewolson.dragon
  (:gen-class
    :extends javax.swing.JFrame))

(defn -paint [this graphics]
  (prn :paint-called)
  (doto graphics
    (.drawString "Hello, World" 20 20)))
 
(defn -main []
  (let [dragon (new org.drewolson.dragon)]
    (doto dragon
      (.setSize 300 300)
      (.setVisible true))))

; -- or --

(ns org.drewolson.dragon
  (:gen-class))

(defn -main []
  (let [dragon (proxy [javax.swing.JFrame] []
                 (paint [graphics]
                   (prn :paint-called)
                   (doto graphics
                     (.drawString "Hello, World" 20 20))))]
    (doto dragon
      (.setSize 300 300)
      (.setVisible true))))