Specification update to clarify Matcher behavior to include a null return value.
------------- Commit messages: - 8217496 Matcher.group() can return null after usePattern Changes: https://git.openjdk.java.net/jdk/pull/5827/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5827&range=00 Issue: https://bugs.openjdk.java.net/browse/JDK-8217496 Stats: 6 lines in 1 file changed: 4 ins; 0 del; 2 mod Patch: https://git.openjdk.java.net/jdk/pull/5827.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/5827/head:pull/5827 PR: https://git.openjdk.java.net/jdk/pull/5827
