code: public Collection<User> getFavorites(String photoId, int perPage, int page) throws FlickrException {
          Map<String, Object> parameters = new HashMap<String, Object>();
  
          parameters.put("method", METHOD_GET_FAVORITES);
  
          parameters.put("photo_id", photoId);
  
          if (perPage > 0) {
              parameters.put("per_page", Integer.toString(perPage));
          }
  
          if (page > 0) {
              parameters.put("page", Integer.toString(page));
          }
  
          Response response = transport.get(transport.getPath(), parameters, apiKey, sharedSecret);
          if (response.isError()) {
              throw new FlickrException(response.getErrorCode(), response.getErrorMessage());
          }
          List<User> users = new ArrayList<User>();
  
          Element userRoot = response.getPayload();
          NodeList userNodes = userRoot.getElementsByTagName("person");
          for (int i = 0; i < userNodes.getLength(); i++) {
              Element userElement = (Element) userNodes.item(i);
              User user = new User();
              user.setId(userElement.getAttribute("nsid"));
              user.setUsername(userElement.getAttribute("username"));
              user.setFaveDate(userElement.getAttribute("favedate"));
              users.add(user);
          }
          return users;
      }
docs: Returns the list of people who have favorited a given photo.
  
  This method does not require authentication.
  
  @param photoId
  @param perPage
  @param page
  @return List of {@link com.flickr4java.flickr.people.User}