Re: Java > 1.5

[Andrew Haley <aph@redhat.com>]

On 16/08/14 10:43, Ruben De Smet wrote:
> On 08/16/2014 10:13 AM, Andrew Haley wrote:
>> On 15/08/14 18:54, Ruben De Smet wrote:
>>> Dear java@gcc.gnu.org list,
>>>
>>> I've gotten to compile some things with GCJ (hooray!) which don't run
>>> fine (ooooh). If I don't come to run it on my own, I'll certainly file a
>>> bug report or contact this list.
>>>
>>> I would like to avoid having to distribute a Java runtime to users, but
>>> my teammate is writing code in Java 1.7. I read GCJ only understands 1.5.
>>>
>>> Is there any development going on for Java 1.7? Would it be a lot of
>>> work to implement some Java 1.7 features? I would take it on me if needed.
>>
>> Right now there's not much prospect of that.  The problem is the class
>> libraries, which would require a lot of work. The best prospect is to
>> convert libgcj to use the libraries from OpenJDK, which would work,
>> but again the conversion would take maybe 6 months for someone who
>> knows gcj very well, along with some compiler changes.  It could be
>> done, but there needs to be a compelling reason.
> 
> Is there any reason gcj isn't yet using OpenJDK libraries, or is it just
> that you didn't think of that yet?

It's a lot of work.  libgcj has its own interface to gcj, and we'd need
to convert it to the interface the openJDK libraries use.

> I guess you'll have to implement all the new 1.6 and 1.7 Java features
> to get the OpenJDK libraries to work?

Yes, but that's less of an issue.

>>> There were two things I noticed with my teammates code that were using
>>> 1.7 features. @Override on interfaces and multi exception catch (like
>>> catch (IOException | OtherException e) ).
>>
>> I'm sure it's possible.
> 
> What would it take me to implement them? Should I CC a devel-mailinglist
> right here?

Sure.  But I don't quite understand what you want me to tell you.  You'd
need to understand the problem and figure out how to fix it.

Andrew.