RFR: 8263399: CDS should archive only classes allowed by module system

[Yumin Qi]

On Thu, 11 Mar 2021 01:08:16 GMT, Ioi Lam <iklam at openjdk.org> wrote:

> `ClassListParser::load_current_class()` tries to archive a boot class from `-Xbootclasspath/a` into the unnamed package, even if the module system forbids this class from being defined in the unnamed package.
> 
> Such classes, even if archived, won't be usable at runtime anyway. The only test case affected by this code is test/hotspot/jtreg/runtime/cds/appcds/jigsaw/classpathtests/BootAppendTests.java, which asserts that such class must be archived, but also asserts that such archived classes cannot be used at runtime. So the first assert seems unnecessary and should be removed.
> 
> The main change is in classListParser.cpp.
> 
> The change in metaspaceShared.cpp is necessary because the `Preload Warning: Cannot find %s"` message was sometimes printed only in the code path that I've deleted.

LGTM.

-------------

Marked as reviewed by minqi (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/2929