> 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: Test case changes: - Test all boot layer modules instead of just the java.sql module - Reduce the number of processes launched for reproducibility testing from 50 to 2 ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/6078/files - new: https://git.openjdk.java.net/jdk/pull/6078/files/dee4197f..3552edf0 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6078&range=09 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6078&range=08-09 Stats: 74 lines in 1 file changed: 16 ins; 35 del; 23 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
