bug#9088: Java, JARS primary?

[Michael Zucchi]

Hi again,

I (mostly) just have an observation to add to the bug tracker discussion
on the dependency generation.

Using $? will not suffice as a dependency check, as it's trivially easy
to create an example which will compile ok after a change but create a
broken jar. e.g. add a new abstract method to an abstract class but
forget to fix all sub-classes.

So without compiler support for dependency generation I think the only
practical solution will be to build all files every time.  Even the
sub-directory holding the classes will probably need to be wiped away
otherwise the jar could contain extraneous classes no longer generated
from the corresponding source which would probably not be a good thing.

I have had a bit of a look at automake.in and some of the .am files - it
seems to me it would not be any use using the existing in built language
code as that is designed for 1:1 source:object compilation.

But before I get too bogged down in that I think I will first try to
create a simple Makefile with the required features for discussion, and
then worry about how to generate it.  Most of it should be
straightforward apart from deciding on conventions.

Regards,
 Michael