Summary

Define JNIDetachReleasesMonitors as obsolete

Problem

The JNIDetachReleasesMonitors flag was added to JDK 6 when it was realized that the VM was not compliant with the JNI specification regarding the release of monitors when a JNI attached thread detached - see JDK-6336479, and also:

http://www.oracle.com/technetwork/java/javase/adoptionguide-137484.html#2.1.1

The flag allowed for restoration of the incorrect behaviour if an application was somehow relying on it. By now all applications should themselves be JNI-spec compliant and this workaround should not be needed, so the flag should be removed.

Solution

We can obsolete the JNIDetachReleasesMonitors flag in JDK 9 (accept it, report it is obsolete and ignore it) and then expire (remove) it in JDK 10.

Specification

The JNIDetachReleasesMonitors flag is made obsolete. It's use will be accepted, but trigger no action other than issuing an informational message that the flag is now obsolete.