Where do empty compilation units belong?

[Alex Buckley]

On 11/19/2018 9:27 PM, Jayaprakash Artanareeswaran wrote:
> I have the following folder structure in a module
>
> my.module
>           -module-info.java
>           - p
>               -- C.java
>               -- q
>                   --- D.java
>
> where C.java contains only the package declaration and D.java is
> empty.
>
> When I run javac with --module-source-path and all the individual
> files as arguments the compiler is happy and reports no error. This
> behavior is different from Eclipse compiler which reports an error
> about "declaring a named package because this compilation unit is
> associated to the named module". Is this because empty compilation
> units are considered to be part of unnamed modules or because the
> D.java and hence package q are omitted?

 From the above, it's hard to understand for which file an error is 
reported by Eclipse. In any case, as Jon indicated, if the file D.java 
is empty, then there is no stream of tokens matching the JLS 7.3 
production `CompilationUnit` and thus there is no compilation unit to 
discuss.

In contrast, the file C.java does contain a compilation unit and I would 
expect it to be "associated" (JLS 7.3 again) with the `my.module` module 
like any other compilation unit contained in a file in the same 
directory. It is legal to annotate the package declaration in the 
compilation unit contained in C.java (let's not rathole into a 
discussion about package-info.java), and the types that can be used in 
the annotation are determined by what `my.module` reads.

Alex