code: @SuppressWarnings ("WeakerAccess")
      public Long getLong (int index) {
          String string = getString (index);
          return (string != null) ? Long.parseLong (string) : null;
      }
docs: Retrieve an indexed element and return it as a Long.
  
  @param index An integer value specifying the offset from the beginning of the array.
  @return The element as a Long, or null if the element is not found.