Read a Java Properties file into a map (with potentially nested keys).

props.clj

(ns ^{:doc "Read Java properties file."
      :author "Baishampayan Ghose <b.ghose@gmail.com>"}
  in.freegeek.props
  (:import java.util.Properties)
  (:require [clojure.java.io :refer [resource reader]]
            [clojure.string :refer [split]]))

(defn- load-props
  "Load a Java properties file. File should be in classpath."
  [props-file]
  (doto (Properties.)
    (.load (-> props-file resource reader))))

(defn- key->path
  [k]
  (map keyword (split k #"\.")))

(defn read-props
  "Read a Java properties file into a map."
  [props-file]
  (let [props (load-props props-file)]
    (reduce (fn [res k]
              (assoc-in res (key->path k) (get props k)))
            {}
            (keys props))))

sample.properties

name = configuration-clj
version = 0.2.4

db.name = whacko-db
db.host = example.org
db.port = 4567

ring.handler.ns = some-ring-handler-ns
ring.handler.protocol = binary