The JDK implementation contains sun.nio.ByteBuffered class that is no longer used and should be deleted together with other related code in sun.misc.Resource and java.net.URLClassLoader.

Its intent was to avoid copying of data during class-loading and use ClassLoader.defineClass method operating directly on a ButeBuffer that maps portion of JAR file into memory but this path is not used in Mustang builds where only central catalogue is mapped into memory.