code: public static <R> R getStaticField(Class<?> clazz, String fieldName) {
      try {
        return getStaticField(clazz.getDeclaredField(fieldName));
      } catch (Exception e) {
        throw new RuntimeException(e);
      }
    }
docs: Reflectively get the value of a static field.
  
  @param clazz Target class.
  @param fieldName The field name.
  @param <R> The return type.
  @return Value of the field.