On Sat, 11 Mar 2023 17:00:18 GMT, Alan Bateman <al...@openjdk.org> wrote:
>> `buildModules` is expected to be called with additional packages but instead
>> it's called with all packages including all exported and open packages.
>>
>>
>> /**
>> * Build a module descriptor into a byte array.
>> * @param moduleAttribute the {@code Module} attribute
>> * @param packages additional module packages
>> * @param handler a handler that receives a {@link ClassBuilder}
>> * @return the classfile bytes
>> */
>> public static byte[] buildModule(ModuleAttribute moduleAttribute,
>> List<PackageDesc> packages,
>> Consumer<? super ClassBuilder> handler)
>> {
>>
>>
>> I checked the implementation that seems to match `@param packages` that
>> expects additional module packages that are not exported nor open. If it
>> intends to take additional packages, it will need to filter the exported and
>> open packages at the callsite.
>>
>> Or the `packages` parameter lists all packages that will be used to create
>> `ModulePackages` attribute. This seems to be easier to understand.
>
> Maybe the variants of Classfile.buildModule need to be looked at again. For
> the usage here, buildModule(ModuleAttribute, Consumer<? super ClassBuilder>)
> would be more useful as it would allow all of the additional attributes to be
> emitted in the handler rather than having buildModule making the decision on
> whether to emit the ModulePackages attribute.
`Classfile::buildModule` is a helper method simplifying the major use case -
building valid module with minimal user effort and knowledge. It emits
`ModulePackages` if there are any packages specified and not exported nor
opened. That is the configuration which JVM expects and majority of users are
not aware of.
Other module-specific attributes can be added in the underlying handler, using
`ClassBuilder::with`.
A different building approach can be used in cases (which I would like to know
more about) where even `ModulePackages` attribute needs to be "customised" or
provided unconditionally. It is always possible to build module as a class
using `Classfile::build` from scratch and provide all the attributes manually.
-------------
PR: https://git.openjdk.org/jdk/pull/11368
