Unquote a java method in clojure

Question

How do I parameterize calls methods in Clojure?

Example:

(def url (java.net.URL. "http://www.google.com"))
(.getHost url) ;; works!
(def host '.getHost)
(host url) ;; Nope :(
(~host url) ;; Nope :(
(eval `(~host url)) ;; Works :s

Answer 1

Right solution (updated clojure 1.12):

(def url (java.net.URL. "http://www.google.com"))
(def host java.net.URL/.getHost)
(host url)
=> "www.google.com"

;; old//fully dynamic version
(def host-sym 'getHost)
(defn dynamic-invoke
  [obj method & arglist]
  (.invoke (.getDeclaredMethod
             (class obj) (name method) nil)
           obj (into-array arglist)))
(dynamic-invoke url host-sym)