在 Leiningen 项目中使用 Emacs 中的 Java

Question

There's plenty of closely related questions on SO, just to name some of them:

• Java and Clojure with Leiningen
• What is the best way to do Java development in Emacs?
• Best java tools for emacs

The difference of my questions is that I want to know how to make working with Java as easy as with Clojure right from Emacs within mixed Clojure/Java Leiningen project.

What I mean is possibility to (in order of priority):

• compile Java code right from Emacs (note: it is possible to compile it from the shell with lein javac )
• use code completion for Java (tools like JDEE provide this feature, but it is separate tool that doesn't concern Leiningen project setup)
• debug Java code

Answer 1

Check out the Emacs LSP project . It provides support for Java.

Answer 2

Probably not what you wanted exactly, but this should handle bullet 1 for ya:

(defun lein-javac (&optional PROJECT-DIR)
  (interactive)
  (let ((output-buffer (progn
                         (with-output-to-temp-buffer "*lein-javac*" nil )
                         (select-window (get-buffer-window "*lein-javac*"))
                         (read-only-mode 'toggle)
                         (window-buffer)) ))
   (shell-command (concat "cd " (or PROJECT-DIR default-directory) 
                         " && lein javac &") "*lein-javac*")))

Answer 3

I want to try auto complete but I haven't gotten to it yet.

Given the way leiningen/Clojure work anyway, I'm not sure how easy you could make compilation. When you compile Java code, don't you have to restart the repl/application for the JVM to reload it anyway?

Answer 4

Malabar-mode is abandonware but I think it's shooting for the level of functionality that you want. It seems to me that a coprocess-based autocompletion engine should be feasible with CEDET, leiningen, and swank-clojure, but I have a day job and side work...