jpa - JPQL Aggregation return -


lets have following jpql query

select e.column1, e.column2, sum(e.column3), sum(e.column4) entity e group e.column1, e.column2

obviously wont returning entity object bit more complex. how return in method?

public list<???> query1() {     query q = entitymanager.createquery("...");     list<something???> list = q.getresultlist();     return list; }

such query returns list<object[]>, each element array of objects. first element of array have type of entity.column1, second 1 have type of entity.column2, , last 2 ones (with hibernate @ least) of type long (check eclipselink).

it's transform list<object[]> in list<foo>, looping on list of objects , transforming each 1 foo. may use constructor notation directly in query (provided foo has such constructor), dislike it, because isn't refactorable:

select new com.baz.bar.foo(e.column1, e.column2, sum(e.column3), sum(e.column4)) ...

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