Re: Interface gcj-compiled library with Java programs in a runtime (other than gij)?

[Yi Lin <qinsoon@gmail.com>]

Thank you all for the answers. I think I have some clue about CNI/JNI on 
the interface.

But I still have doubt about how a shared library compiled from Java can 
be used by a) c/c++, b) Java code running on other JVM (not libgcj 
interpreter). I think b) is straightforwad if a) is possible.

So for a), is calling a shared library of compiled java code any 
different than calling a shared library from normal c/c++ code? I have 
been spending two days exploring this and trying different approaches. 
My expectation is to load the compiled Java lib and use its method via 
dlopen, dlsym, etc. I guess another possibility is to use JvCreateVM(), 
and do everything in Java fashion. I don't have any success in either 
yet. Any hint would be very helpful so I could stop wasting time on a 
wrong track.

Thanks,
Yi

On 2012/2/14 21:31, Bryce McKinlay wrote:
> On Tue, Feb 14, 2012 at 9:47 AM, Andrew Haley<aph@redhat.com>  wrote:
>> On 02/13/2012 06:32 PM, David Daney wrote:
>>> I am just going from memory here, but I think that the interpreter can
>>> only call native code via JNI.
>> Ahh, if that were really true, interpreted code couldn't call
>> Object.<init>() ...
>
> David is saying that "native" methods in interpreted classes can't be
> implemented with CNI. Which is true, I think.
>
> Obviously, the interpreter can call native CNI methods in other
> (non-interpreted) classes, like Object. Hence the trampoline example.
>
> Bryce