code: public static boolean isSingleValueType(Class<?> type) {
  
          LettuceAssert.notNull(type, "Class must not be null!");
  
          return findDescriptor(type).map((descriptor) -> !descriptor.isMultiValue() && !descriptor.isNoValue()).orElse(false);
      }
docs: Returns {@literal true} if {@code type} is a reactive wrapper type for a single value.
  
  @param type must not be {@literal null}.
  @return {@literal true} if {@code type} is a reactive wrapper type for a single value.