Re: [Aegisvm-devel] patch to jni.c

[Gildas B. <gb...@al...>]

On Thursday 25 July 2002 01:54, Philip Fong wrote:
> Hi,
> 
> Hmm, I am usually not very fond of such use of macros.  But I see your
> point though.  The various method invocation routines definitely need
> a lot of factoring.  I am still thinking about how to do this the
> right way.  My experience is that most of the nasty bugs I have seen have
> to do with either the garbage collector or one of the method invocation
> routines.  These functions are extremely delicate, and break very 
> easily.  My fear is that using macro-based templates might make the
> code even more cryptic.  However, I welcome any thoughts you might
> have on this matter.
> 

I am not found of them either ;-)
The main motivation for using such macros is to replace the multitude of 
small wrapper functions that jni.c is using. All the Call##JType##Method*() 
functions are in fact wrappers around ae_jni_CallMethodA()  where the bulk 
of the work is done anyway. ae_jni_CallMethodA() is the important function 
where all the improvements are likely to be done in the future, the 
wrappers themselves shouldn't have to change much.
But I guess this is also a matter of taste ;-)

> > The second part of the changes is an attempt to implement more of the 
JNI 
> > functions. These changes need to be reviewed carefully as I'm not 
entirely 
> > sure I understood all the subtilities involved, even though they all 
seem 
> > to work correctly.
> > List of implemented functions:
> > - all the ae_jni_Call##JType##Method*()
> > - ae_jni_GetFieldID()
> > - all the ae_jni_Get/Set##JType##Field()
> > - ae_jni_GetStringUTFLength()
> > - ae_jni_GetStringUTFChars()
> > - ae_jni_ReleaseStringUTFChars()
> > - ae_jni_GetArrayLength()
> 
> This is perfect!  As I mentioned before, we could probably discuss a bit
> more before we give a good shot at the ae_jni_Call##JType##Method*()
> functions, but it would be extremely nice if you would be able to help
> out with implementing the rest.  Thanks in advance.
> 

If you want me to send you a patch without the macros I can do it (not that 
I will like to do it, but I can ;-).

One of the reasons why I started implementing these JNI functions is that 
I'm trying to run the mauve java testsuite 
(http://sources.redhat.com/mauve/) on AegisVM but the testsuite doesn't 
even bootstrap with the current AegisVM cvs because of missing JNI 
functions and a few other things. It's almost working though and I will 
send you the remaining patches when it is.

> 
> BTW, which release (or cvs tag) was your previous patch made out of?
> 
Current cvs :)

Regards,

--
Gildas