make identification variables (and the SELECT) clause optional in JPQL

[gavinking]

This is a minimal change to support the subset in Jakarta Data i.e. it is only allowed when there is just one thing in the FROM clause.

see #452

[gavinking]

Interesting. I came up with an alternative approach that in certain ways is even more "minimal".

We could say that whenever the identification variable is missing (in a range declaration, or in a path expression) then it is implicitly assigned the variable this.

So you could write:

select this from Entity where name like :name

And that would be equivalent to:

select this from Entity this where this.name like :name

I actually like this quite a lot. WDYT @lukasj?

[gavinking]

We could say that whenever the identification variable is missing (in a range declaration, or in a path expression) then it is implicitly assigned the variable this.

I pushed a second commit which shows what that would look like.

[lukasj]

it looks better with this, thanks!

[gavinking]

Awesome! 🎉🎉🎉