Question about javac and modules exporting the same packages at compile time

[Florian Troßbach]

Hi,

Playing a bit more with Jigsaw, i was surprised by the behaviour of javac
and would like to inquire about the motivation for this.

I have three modules. One module reads the other two which have different
module names but are otherwise identical. Compiling this, I get a load of
compiler warnings about the same packages, but it compiles just fine. I
assume it compiles it against the first version of a class it finds.

When I run the application, I get a java.lang.module.ResolutionException,
so this is good. My question is though - this could have been a compile
error too, but the compiler tolerates it. What is the motivation behind
this?

Best regards,
Florian