Make `BYTES_PER_*` constants public in `DataSize`

[albertus82]

At the moment the constants in org.springframework.util.unit.DataSize are private and cannot be used, for example, in annotations, so we have to bloat our code with 1024 everywhere.

Thanks.

[sbrannen]

Hi @albertus82,

Those constants in DataSize are intentionally private because they represent an internal implementation detail.

One normally uses one of the static parse(...) methods in DataSize to parse a data size string, and DataSize.parse(CharSequence, DataUnit) accepts a DataUnit in case you need to specify one.

Note that Spring Boot also has built-in support for converting application properties to DataSize values. See Converting Data Sizes for details.

At the moment the constants in org.springframework.util.unit.DataSize are private and cannot be used, for example, in annotations, so we have to bloat our code with 1024 everywhere.

Can you please provide concrete examples of how you are using DataSize?

For example, which annotations are you talking about?

Cheers,

Sam

[albertus82]

Hi @sbrannen,

Those constants in DataSize are intentionally private because they represent an internal implementation detail.

Commons IO contains something similar in its org.apache.commons.io.FileUtils class.

IMHO those constants are actually only some specific powers of two. You might reword them before making them public if their name represent an implementation detail (and maybe keep the private ones referencing the public ones).

For example, which annotations are you talking about?

e.g. @jakarta.validation.constraints.Size (on arrays).

Thanks.

[sbrannen]

Thanks for the feedback, @albertus82.

For what it's worth, the min and max attributes in Bean Validation's @Size annotation are of type int; whereas, the constants in DataSize are of type long. So, that's not a good match.

In any case, the constants in DataSize are not intended for public consumption, and we would like to keep it that way. We feel that the API provided by the static parse(...) methods in DataSize and the support for automatic conversion of property values to DataSize in Spring Boot are sufficient for the needs of Spring applications.

If you have a concrete need for similar constants, you can use the ones in Commons IO as you mentioned. Otherwise, you can easily create public constants within your project for such purposes.

In light of the above, I am closing this issue.

Regards,

Sam