From: Florian Gilcher <flo@...>
Date: 2008-11-19T22:28:59+09:00
Subject: Re: JRuby on Android (from: What would you like to know about Jruby?)

First of all, thanks for the answer. As I see, it is not just a wild  
guess.

On Nov 19, 2008, at 2:04 PM, Charles Oliver Nutter wrote:

> Admittedly, I have not spent a lot of time looking at Android, but  
> I'm certain it would be possible to produce a modified version of  
> JRuby that could run on it. In the end, there's only a few key  
> pieces that would need to work:
>
> - The code would either need to be always interpreted or  
> precompiled, since we can't generate Java bytecode on Android at  
> runtime.

Okay, this was the first problem I ran into. But i had a hard time to  
asses how far JRuby depends on this. So I lost interest (you know...  
fun project). Do you think this is solvable in a clean way with not  
too much of work?

> - We would need to trim the core classes to those that would work on  
> Android, and then to methods supported by Android.

Trimming the package would be needed anyways, I don't see a problem  
there.

> - Finally, we'd need a bytecode backporting tool if 1.5 bytecode was  
> not acceptable. There are various "retro" tools that do a pretty  
> good job.

I played around with some, but they were a bit troublesome. The  
biggest problem is that they generate JVM Bytecode which is different  
from the Bytecode the Android VM uses. There is a converter, but I had  
my problems with that one, too.

> So it's certainly possible, but I don't think anyone's started  
> looking at it. It would take a bit of work.
>
> - Charlie

Thanks for the info. Maybe I will have a look into it again.

Regards,
Florian Gilcher