Emacs java-mode: malabar, jdee, or eclim?

Question

I want to use emacs for java coding, but I'm confused on what mode to use for java coding. There's jdee, which seems ide-like; malabar, who is said to be more well versed in java 1.5 constructs than jdee; and emacs-eclim, which is an eclipse backend for emacs. There are also a wealth of completion extensions for emacs, and I'm also confused on which one to use. In fact, I'm so confused that I deferred using any of them until I get recommendations.

What is the current best option for java-mode + completion in emacs? And, if ever I decide to use a combination of what I mentioned above, will conflicts happen?

Answer 1

For those used to the power of Emacs text manipulation then Eclipse can seem like pedaling a bicycle with one foot. The Emacs+ plugin from http://www.mulgasoft.com/ is excellent for getting Emacs key bindings into Eclipse.

I use both Eclipse and Emacs a lot, but if I only did Java development I might use only Eclipse with Emacs+. It takes some work to get many Eclipse features enabled on Emacs.

My advice is to use Emacs >= 23. If you are on a Mac, look at AquaMacs. I use JDEE as the Java plugin. This has the serious drawback of not playing well with generics. It's not that it stops working, it's just that a lot of stuff isn't recognized. Do not use the old 2.3.5 JDEE plugin (that comes with most Linux distributions), but get the 2.4 version from the sourceforge site. Also get the Emacs Code Browser (ECB); this is a plugin that will give you stuff like Eclipse's Project Explorer and Outline views (other developers will look at this and not believe you when tell them that it's Emacs). I've used this setup for commercial projects on Windows, Mac, and Linux in the past year.

In fact, Eclipse plays pretty well with Emacs and I often switch between the two. Eclipse has some nice refactoring tools that I used to use sed for, and it has a good debugger interface. You can use them simultaneously. I find that I use Eclipse when working with other people's code and Emacs when I am writing my own code---Emacs is that much faster. Note that for me, a lot of the value of Emacs is the non-Java functionality, like editing Tomcat configuration files on remote servers from my local Emacs, writing professional documents with LaTeX, developing in Python or Bash or MATLAB or XML, and the odd text manipulation task (e.g., converting CVS files into String[] arrays).

I haven't used the other two projects you mention. It is possible to use the Eclipse compiler with Emacs already, so I'm not sure I see the point of the emacs-eclim project, which seems to be moribund anyway. The Malabar project might be interesting, but seems to be the product of one somewhat cranky developer (e.g., the warning "if you're not using Maven (why?) you should not consider malabar-mode"---I'll tell my clients that?).

Java on Emacs is in a sad state. I wish for JDEE to be revitalized, but it's not clear when or if that will happen. The web site and mailing list offer few clues.

Answer 2

I use emacs-eclim with auto-complete-mode support and java-mode highlighting exclusively for Java programming. 90% of my work is done in emacs, but I switch to eclipse when I need to debug, run unit tests or do major refactorings. All in all, this setup works very well for me.

I haven't tried JDEE for years, but I remember it was a b*tch to set up. I didn't care for the UI very much, as it put up lots of prearranged windows that were locked in place. I like to be able to switch back and forth between editing buffers, often showing just one window, but splitting and rearranging on the fly when it becomes necessary.

Note: I am an emacs-eclim maintainer, and this has probably coloured my judgement.

Answer 3

If you're using Maven, then I'd recommend malabar-mode. It will set everything up for you automagically, no need for editing project files like you'd have to do with JDEE. The downside I've found with malabar, is that it can consume a lot of memory if you've got a lot of multi level module projects open.

Both Malabar and JDEE will give you "true" completion, i.e. only completions that are possible. However, there are two amazing "intelligent guessing completion frameworks" in Emacs. hippie-expand and auto-complete.

The former is great (can complete whole code blocks for you, making it possible to e.g. cycle through all if-tests in your projects), but auto-complete mode is even better. It'll give you a nice intelli sense style menu, will "learn" as you use it, and allows you to define a file with the completions you'd like to be available in the various languages.