Question on SharedDictionary

[yumin qi]

Hi, Ioi

  In set_shared_dictionary(..):
void SystemDictionary::set_shared_dictionary(HashtableBucket<mtClass>* t,
int length,
                                             int number_of_entries) {
  assert(length == _shared_dictionary_size *
sizeof(HashtableBucket<mtClass>),
         "bad shared dictionary size.");
  _shared_dictionary = new
Dictionary(ClassLoaderData::the_null_class_loader_data(),
                                      _shared_dictionary_size, t,
number_of_entries);
}

I just wonder why not using SharedDictionary here?
Searched workspace (11) for SharedDictionary, looks it is not used (as
instance object). There is many cast from DictionaryEntry to
SharedDictionaryEntry, there should be not many if _shared_dictionary is an
instance of SharedDictionary, right?

Thanks
Yumin