JTree from a clojure collection

Clojure JTree.clj

; Turn a map into a JTree
; keys can be any object using toString to display
; listener is called as (listener seq-of-keys-to-selected-node)

;root
; |-child-1
; | |-Child-1-1
; | |-child-1-2
; |-child-2
; |-child-3
;   |-child-3-1

{"root" {"child-1" {"child-1-1" nil
		    "child-1-2" nil}
	 "child-2" nil
	 "child-3" {"child-3-1" nil}}}

(import [javax.swing.tree DefaultMutableTreeNode TreeSelectionModel]
	[javax.swing JFrame JTree JScrollPane SwingUtilities])

(defn create-nodes [root coll]
  (doseq [[obj sub-nodes] (seq coll)
	  :let [node (DefaultMutableTreeNode. obj)]]
    (.add root node)
    (if sub-nodes (create-nodes node sub-nodes))))

(defn with-listener [tree listener]
  (.addTreeSelectionListener tree
    (proxy [javax.swing.event.TreeSelectionListener] []
      (valueChanged [event] (->> event
				 .getPath
				 .getPath
				 (map #(.getUserObject %))
				 listener)))))

(defn map->jtree
  [map listener]
  (let [[root-obj nodes] (first map)]
    (doto (JTree. (doto (DefaultMutableTreeNode. root-obj)
		    (create-nodes nodes)))		  
      (.. getSelectionModel
	  (setSelectionMode
	   TreeSelectionModel/SINGLE_TREE_SELECTION))
      (with-listener listener))))

(defn display-tree
  "A simple container and display frame to show a JTree for debugging"
  [#^JTree tree]
  (SwingUtilities/invokeLater
   #(doto (JFrame. "TreeView")
      (.setDefaultCloseOperation JFrame/DISPOSE_ON_CLOSE)
      (.setContentPane (JScrollPane. tree))
      (.pack)
      (.setVisible true))))

(display-tree (map->jtree
	       {"root" {"child-1" {"child-1-1" nil
				   "child-1-2" nil}
			"child-2" nil
			"child-3" {"child-3-1" nil}}}
	       println))