public static <E> void onFailure(HttpRequestHandler<E> handler, String error) {
   try {
     handler.onFailure(error);
   } catch (Exception e) {
     e.printStackTrace();
   }
 }
 public static <E> void onSuccess(HttpRequestHandler<E> handler, E data) {
   try {
     handler.onSuccess(data);
   } catch (Exception e) {
     e.printStackTrace();
   }
 }
 public static <E> void onSuccess(
     HttpRequestHandler<E> handler, E data, int totalPages, int currentPage) {
   try {
     handler.onSuccess(data, totalPages, currentPage);
   } catch (Exception e) {
     e.printStackTrace();
   }
 }