Two ways to call private methods in Clojure.

private.clj

;; This fn allows calling any method, as long as it's the first with that name in getDeclaredMethods().
;; Works even when the arguments are primitive types.

(defn call-method
  [obj method-name & args]
  (let [m (first (filter (fn [x] (.. x getName (equals method-name)))
                         (.. obj getClass getDeclaredMethods)))]
    (. m (setAccessible true))
    (. m (invoke obj (into-array Object args)))))


;; This function comes from clojure.contrib.reflect. A version of it is also in https://github.com/arohner/clj-wallhack.
;; It allows calling any method whose arguments have class types, but not primitive types.

(defn call-method
  "Calls a private or protected method.
   params is a vector of classes which correspond to the arguments to the method
   obj is nil for static methods, the instance object otherwise.
   The method-name is given a symbol or a keyword (something Named)."
  [klass method-name params obj & args]
  (-> klass (.getDeclaredMethod (name method-name)
                                (into-array Class params))
      (doto (.setAccessible true))
      (.invoke obj (into-array Object args))))