static "extra-lazy" operations for collections

[gavinking]

I would like to remove extra-lazy collections from Hibernate 6.

But instead of just killing them without providing any way to achieve the same thing, we could easily add some operations like:

Hibernate.getSize(my.getItems())
Hibernate.get(my.getMap(), key)
Hibernate.contains(my.getItems(), item)
Hibernate.remove(my.getItems(), item)
Hibernate.put(my.getMap(), key, value)

So that you can do item-level operations on a collection without actually loading it.

Reactions to this idea?

FTR I don't think it would be hard for me to implement it. OTOH, it's code, and code must be maintained.

[Sanne]

I do like the new helpers you're proposing, but I'm skeptical of removing the extra-lazy capability.

So reasons to keep the extra-lazy:

• People know it, and it's a useful feature even in its current shape (albeit limited)
• When mapping a relation as a Map<k,v> it allows loading selected keys only, even by code which is oblivious of the object being managed, and not having to depend on Hibernate.
• It allows loading patterns which are beneficial to make optimal use of the 2LC

Reasons to introduce such a new API as well (eventually?):

• It allows more fine grained control, e.g. get only the size without having to load it all, and we could implement contains as a boolean-returning SQL w/o actually loading the entry (not sure if that's actually a good idea, my point being we'd have more such options)
• It allows performing such optimisations even if the extra-lazyness wasn't specificed on the mapping; it's great to focus more on the use case rather than enforce a single option via static mapping.

[beikov]

So this feature is here to stay as we figured it is indeed useful and people actually use it.

[gavinking]

Right, it seems so. But the proposal to add operations to the Hibernate class is still live.

[gavinking]

This is implemented in #5094.