If a thread-safe implementation is not needed, it is recommended to use HashMap in place of Hashtable. `ConditionalSpecialCasing.entryTable` is read-only Map which is modified only in `static` block. It means we can safely replace it with HashMap.
------------- Commit messages: - [PATCH] Unnecessary Hashtable usage in ConditionalSpecialCasing Changes: https://git.openjdk.org/jdk/pull/9172/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9172&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8288628 Stats: 4 lines in 1 file changed: 1 ins; 1 del; 2 mod Patch: https://git.openjdk.org/jdk/pull/9172.diff Fetch: git fetch https://git.openjdk.org/jdk pull/9172/head:pull/9172 PR: https://git.openjdk.org/jdk/pull/9172