> Can I please get a review for this change which fixes the issue reported in 
> https://bugs.openjdk.java.net/browse/JDK-8275509?
> 
> The `ModuleDescriptor.hashCode()` method uses the hash code of its various 
> components to compute the final hash code. While doing so it ends up calling 
> hashCode() on (collection of) various `enum` types. Since the hashCode() of 
> enum types is generated from a call to `java.lang.Object.hashCode()`, their 
> value isn't guaranteed to stay the same across multiple JVM runs.
> 
> The commit here proposes to use the ordinal of the enum as the hash code. As 
> Alan notes in the mailing list discussion, any changes to the ordinal of the 
> enum (either due to addition of new value, removal of a value or just 
> reordering existing values, all of which I think will be rare in these 
> specific enum types) isn't expected to produce the same hash code across 
> those changed runtimes and that should be okay. 
> 
> The rest of the ModuleDescriptor.hashCode() has been reviewed too and apart 
> from calls to the enum types hashCode(), rest of the calls in that 
> implementation, either directly or indirectly end up as calls on 
> `java.lang.String.hashCode()` and as such aren't expected to cause 
> non-deterministic values.
> 
> A new jtreg test has been added to reproduce this issue and verify the fix.

Jaikiran Pai has updated the pull request incrementally with one additional 
commit since the last revision:

  remove unintentional change in test case

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6078/files
  - new: https://git.openjdk.java.net/jdk/pull/6078/files/065c3118..e8f19d82

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6078&range=07
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6078&range=06-07

  Stats: 7 lines in 1 file changed: 0 ins; 6 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6078.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6078/head:pull/6078

PR: https://git.openjdk.java.net/jdk/pull/6078

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