Simulation of Ring network topology using Agents in Clojure

ring.clj

(ns net.abhinavsarkar
  (:use [clojure.contrib.import-static]))

(import-static java.lang.Integer parseInt)

(def no-of-nodes
  (do
    (println "Number of nodes? ")
    (parseInt (read-line))))

(def no-of-probes
  (do
    (println "Number of probes? ")
    (parseInt (read-line))))

(def nodes (vec (map #(agent [% 0]) (range no-of-nodes))))

(defn wrap-id [id]
  (if (< id no-of-nodes)
      id
      (mod id no-of-nodes)))

(defn message-rate [start-time count id]
  (*
    (+ (* count no-of-nodes) id)
    (/ 1e9 (- (System/nanoTime) start-time))))

(defn message [[id count] start-time]
  (do
    (send (nth nodes (wrap-id (inc id))) message start-time)
    (when (zero? (mod id (/ no-of-nodes no-of-probes)))
      (println
        (format "%.0f messages/sec"
          (message-rate start-time count id))))
    (vector id (inc count))))

(send (first nodes) message (System/nanoTime))