naaman

Hot Swapping With Maven, Jetty and IntelliJ

Based on Configuring Jetty, Maven, and Eclipse together with Hot Swap

I've always been a bit jealous when it comes to the Play! framework and the great dev mode they have for hot swapping classes at runtime. Jetty has a configuration setting, scanIntervalSeconds, that mimics this when working with a more traditional WAR, but does so by looking for changes to a file and restarting the server.

Fortunately, Jetty also provides the ability to rapidly test code with hot swapping. No more server restarts. The trick to getting hot swapping to work is to attach a remote debugger to your Jetty process. The following instructions outline how to do this in IntelliJ (tested with IDEA 10.5 CE).

Modify your jetty-maven-plugin to ignore the scan interval

1. Open your pom and locate the plugins section

jramb

((ns excel.core
  (:import [org.apache.poi.hssf.usermodel HSSFWorkbook HSSFSheet HSSFRow
            HSSFRichTextString HSSFFont HSSFDataFormat 
            HSSFCellStyle HSSFCell])
  (:import [java.io FileOutputStream FileInputStream IOException])
  #_(:import [org.apache.poi.ss.util CellRangeAdrress]))


(defn make-excel [file-name]
  (let [wb (HSSFWorkbook.)

powerset.clj

(use '[clojure.set]
     '[clojure.test])
(defn powerset [ls]
  (if (empty? ls) '(())
      (union (powerset (next ls))
	    (map #(conj % (first ls)) (powerset (next ls))))))

(deftest test-powerset
  (is (= '(()) (powerset '())))
  (is (= '((1) ()) (powerset '(1))))

ghoseb

;;
;; NS CHEATSHEET
;;
;; * :require makes functions available with a namespace prefix
;;  and optionally can refer functions to the current ns.
;;
;; * :import refers Java classes to the current namespace.
;;
;; * :refer-clojure affects availability of built-in (clojure.core)
;;   functions.