SimpleJavaFileObject specification would benefit from implSpec

Several of the methods of SimpleJavaFileObject are structured like:

"This implementation always throws UnsupportedOperationException. Subclasses can change this behavior as long as the contract of $METHOD is obeyed."

This idiom would be better captured using an implSpec tag and directed inheritance, something like:

"{@inhertiDoc JavaFileObject}
 @implSpec his implementation always throws UnsupportedOperationException."