@Nonnull
    public static <T> NullableOptional<T> of(@Nullable T value) {
        return new NullableOptional<>(value);
    }
Returns a {@code NullableOptional} with the specified present value.

@param <T> the class of the value
@param value the value to be present
@return a {@code NullableOptional} with the value present
helper/src/main/java/me/lucko/helper/utils/NullableOptional.java