code: public <T> List<Key<T>> getKeysByRefs(final List<DBRef> refs) {
          final List<Key<T>> keys = new ArrayList<Key<T>>(refs.size());
          for (final DBRef ref : refs) {
              final Key<T> testKey = refToKey(ref);
              keys.add(testKey);
          }
          return keys;
      }
docs: Gets the Keys for a list of objects
  
  @param refs the objects to process
  @param <T>  the type of the objects
  @return the list of Keys