code: public T users_getInfo(Collection<Integer> userIds, EnumSet<ProfileField> fields)
      throws FacebookException, IOException {
      // assertions test for invalid params
      assert (userIds != null);
      assert (fields != null);
      assert (!fields.isEmpty());
  
      return this.callMethod(FacebookMethod.USERS_GET_INFO,
                             new Pair<String, CharSequence>("uids", delimit(userIds)),
                             new Pair<String, CharSequence>("fields", delimit(fields)));
    }
docs: Retrieves the requested info fields for the requested set of users.
  @param userIds a collection of user IDs for which to fetch info
  @param fields a set of ProfileFields
  @return a T consisting of a list of users, with each user element
  containing the requested fields.