java - Select elements from joined ElementCollection -

problem description

suppose have data model looks (simplified keep short):

@entity class unit { ... }  @embeddable class numberwithunit {   double value;    @manytoone ( fetch = fetchtype.lazy, optional = false )   @joincolumn(name = "unitid")   unit unit;      }  @entity class product {    @id    int id;     @elementcollection    @collectiontable( name = "sisu" )    list<numberwithunit> sizeinseveralunits; } 

that model might not make sense shows structure need work with.

now we'd issue query this:

select p.id, s product p join p.sizeinseveralunits s 

the problem, however, hibernate 4.3.11 doesn't produce correct sql statement query , don't know (yet) how fix that.

the sql produced looks

select product_.id, sisu_.id product product_ join sisu sisu_ on product_.id = sisu_.productid 

that query fails of course, since there no column sisu_.id. instead hibernate should solve select sisu_.value, sisu_.unitid. in fact, if we'd use single numberwithunit , query hibernate correctly resolve , generate correct sql - if we'd join (it's unnecessary tested anyways).

question

how can individual elements of elementcollection selected in hql/jpql?

what we've tried far

• making use of hibernate specific elements() function, i.e. rewrite query select p.id, elements(p.sizeinseveralunits) product p. works due other reasons we'd use last resort (reasons being we're building framework generates queries , should able create join whenever sees collection in entity etc.).
• we've debugged hqlsqlwalker etc. find out when selecting "one-to-one" numberwithunit ast node type componenttype correct. when using join select elements joined collection type gets bagtype correct collection. after hibernate seems lost , assumes want join entity , tries load id.
• we guessed (but assumed guessing wrong) might unit relation inside numberwithunit causing problem changed simple scalar value test. expected didn't change thing.

what we've though not tried yet

• providing custom user type knows how handle numberwithunit collections of it. if there no standard/better way of solving our problem , works we'd go this.
• testing simpler types, e.g. list<string>.
• upgrading hibernate 5. since ast handling redesigned in hibernate 5 might working in version. upgrading means quite effort , risk break other things in our not-so-small system we'd later when have more resources available.