Support for plain Time fields

[OmarHawk]

Overview of the feature request

Hi,

while there is currrently support for something like an Instant (datetime(6)) there is currently no support for a plain Time value without a Date. Do you think it makes sense to introduce a new data type here as part of JHIpster itself? If so, I'd like to contribute to this.

• Liquibase also supports this https://docs.liquibase.com/concepts/data-type-handling.html by the way.
• Would probably map to LocalTime in Java side.
• Would generate an input using type="time" https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/time

Motivation for or Use Case

We have the use case to define opening hours. With the existing fields you can either have a plain String where the user must enter the correct format with : by himself, or have Datetime like fields, where the user is required to enter a useless Date value.
Of course, we could also try to implement this as a blueprint, but I think, data types are part of the jhipster core, and this seems to be a special data type that is currently not supported....

Related issues or PR

Searching for "Time" finds too much unrelated stuff, so idk.

• Checking this box is mandatory (this is just to show you read everything)

[mshima]

I am ok with this, changing a database type of a field is not accepted in no major versions, but an annotation can be used.

[OmarHawk]

So you mean, this should be implemented with an annotation?

Please note, that this is not a "changed" data type, but a new one, so there should be no backwards compatibility issues as long as one is not using this new type... For consistency reasons I would really vote for having an actual type like Instant, Long, String.... Time.

An Annotation would be useful here to define maybe the resolution of the time (seconds, milliseconds, ...)