RFR(S) 8172288: Fix error message when trying to define an existing package to a module

[Alan Bateman]

On 10/01/2017 15:18, harold seigel wrote:

> Yes.  I'll modify the bug to include that.
>
> What exception should the JVM throw for this?

IllegalStateException might be okay for the cases where the package is 
already defined to another module. Note that you'll need to change 
Layer.java and run the tests the java/lang/module tests. We also have 
changes in jake that are going to have to change too.

The other one is "Module java.base is already defined". If we ever get 
that then the JDK is seriously broken, meaning InternalError but I 
assume you'd prefer to throw IllegalStateException.

-Alan