From: Charles Oliver Nutter <headius@...>
Date: 2011-01-21T14:29:57+09:00
Subject: Re: jruby in a pure java environment

On Thu, Jan 20, 2011 at 12:24 AM, Martin DeMello
<martindemello@gmail.com> wrote:
> I'm curious about JRuby's adoption as a tool in pure Java places - has
> anyone used it in places where all the shipping code had to be in
> Java?
>
> [asked on stackoverflow
> http://stackoverflow.com/questions/4450488/using-jruby-as-a-tool-for-java-programming
> but didn't get many answers]

I weary of stackoverflow. For some reason it seems like the myspace of
tech Q/A forums.

Anyway, about your question...

The biggest use case for JRuby by far is deploying a Ruby application
in a pure Java environment. Usually this takes the form of a Rails or
Sinatra app deployed on a Java server, where native dependencies are
completely disallowed. And for those of you struggling with native
dependencies: yes...you can run a Rails app on JRuby without a single
native gem, bundled up once and deployed on any platform without
rebuilding a thing. Ponder that for a moment :)

Of course the other use case is where people simply want to use a
particular Java library because it's the best or only solution for
their problem, or because they don't want to deal with native
dependencies again.

In general, most uses of JRuby are to take advantage of Java libraries
and the JVM...and I think that's where JRuby will continue to shine
for a long time.

Sure, JRuby's a really good Ruby implementation too, and you don't
have to know or touch Java to take advantage of it. And we'll continue
to improve that side of things into the future. But it's not usually
the primary motivating reason for people to use JRuby.

- Charlie