Javadoc
Given an identified for an existing object, create another handle. This is particularly
useful when using optimistic concurrency control and we need one object instance per
thread to ensure that state is safely managed.
WARNING: if the Uid is invalid, e.g., points to a state that no longer exists, then a handle
will still be returned because checks for validity (other than null parameter) cannot be done
until you try to use the state. At that time a lock will be refused (state cannot be activated)
and a suitable warning message will be output.