Currently, the two subclasses of `java.util.EnumSet` optimize bulk operations when the argument is also a `EnumSet`, but there is no such optimization for wrapper sets (returned by `Collections.unmodifiableSet`, `Collections.synchronizedSet`, etc.) and immutable sets (returned by `Set.of` methods) of `Enum`s.
This PR introduces optimization classes for these situations. No public APIs are changed. ------------- Commit messages: - add `import` in SetFactories.java - Fix typo - Update SetFactories.java - make configure not executable - Update Collections.java - Revert "Merge remote-tracking branch 'origin/optimize-enum-coll' into optimize-enum-coll" - Merge remote-tracking branch 'origin/optimize-enum-coll' into optimize-enum-coll - Check for unmodifiable sets in `unmodifiableSet` - fix error - add tests for Set.of factories - ... and 12 more: https://git.openjdk.org/jdk/compare/e4d1cff6...7f704c35 Changes: https://git.openjdk.org/jdk/pull/12498/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=12498&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8302818 Stats: 723 lines in 8 files changed: 674 ins; 0 del; 49 mod Patch: https://git.openjdk.org/jdk/pull/12498.diff Fetch: git fetch https://git.openjdk.org/jdk pull/12498/head:pull/12498 PR: https://git.openjdk.org/jdk/pull/12498
