Beginning with JRuby

Ruby JRuby
1

Hi
I want to start learning JRuby. But only a beginner to Java. Please
suggest any good tutorial to start step by step

Thanks
Tom

2

On Thu, Sep 15, 2011 at 8:59 AM, Tom M. [email protected] wrote:

I want to start learning JRuby. But only a beginner to Java. Please
suggest any good tutorial to start step by step

Start what? JRuby (any Ruby tutorial will do, there are numerous books
along the lines of “Ruby from beginner to expert/professional”, Java
itself (there’s libraries of Java introductions), or JRuby’s Java
integration?

–
Phillip G.

gplus.to/phgaw | twitter.com/phgaw

A method of solution is perfect if we can forsee from the start,
and even prove, that following that method we shall attain our aim.
– Leibniz

3

or JRuby’s Java
integration?

Hi
Yes I need JRuby’s java integration . So onething I understood is, to
use JRuby I should know Java also. Right?

Thanks

4

Hi
Thanks for your reply. So anything we do with java can be done with
JRuby?
(Please excuse if this is a blunder question.)

5

On Thu, Sep 15, 2011 at 11:10 AM, Tom M. [email protected] wrote:

Yes I need JRuby’s java integration . So onething I understood is, to
use JRuby I should know Java also. Right?

Wrong, actually. :slight_smile: JRuby is first and foremost a full* Ruby
implementation.

However, JRuby can also access Java classes, and you can operate on
them (almost) like they are Ruby objects**.

See for example the JRuby Wiki:
CallingJavaFromJRuby · jruby/jruby Wiki · GitHub or
StackOverflow:
Can I import Java class files into JRuby? - Stack Overflow

  • AFAIK, Ruby 1.9 support isn’t fully complete yet, but most of it
    does work (use it via “$ jruby -v 1.9”), and 1.8 compatibility is
    complete including 1.8.7 (important for Rails!).

** IronRuby in the .NET world works pretty much the same: It’s Ruby
with integration into the runtime it sits on top of (the CLR for .NET,
the JVM for JRuby).

–
Phillip G.

gplus.to/phgaw | twitter.com/phgaw

A method of solution is perfect if we can forsee from the start,
and even prove, that following that method we shall attain our aim.
– Leibniz

6

On Thu, Sep 15, 2011 at 05:03, Tom M. [email protected] wrote:

Hi
Thanks for your reply. So anything we do with java can be done with
JRuby?
(Please excuse if this is a blunder question.)

For the most part, yes. There’s alot of information on their wiki:

In particular, if you’re trying to integrate the Ruby side with Java
libraries, check out this page:

I personally would recommend the book, Using JRuby (
Search), as it does a great job of
explaining how to call out to Java from JRuby as well as how to call
Ruby
from Java. Highly recommended if you’re wanting to do something serious
with JRuby/Java integration.

-Nick

7

On Thu, Sep 15, 2011 at 12:03 PM, Tom M. [email protected] wrote:

Hi
Thanks for your reply. So anything we do with java can be done with
JRuby?
(Please excuse if this is a blunder question.)

As far as I know: Yes (I never needed the JRuby Java integration).
It’s one of the development goals for JRuby.

For example, if you want Ruby’s features, you can use them, and if you
need, say, Java’s math classes, you can integrate them. And, AFAIK,
you can write something in Java, and integrate JRuby as scripting
engine.

–
Phillip G.

gplus.to/phgaw | twitter.com/phgaw

A method of solution is perfect if we can forsee from the start,
and even prove, that following that method we shall attain our aim.
– Leibniz