java - Using hibernate criteria query for joining a not directly referenced entity -

java - Using hibernate criteria query for joining a not directly referenced entity -

i run criteria query on entity using bring together entity. java/hibernate point of view there no reference sec entity, there 1 sec first entity.

to create understandable, here cat'ifized situation:

===== cat.java ===== @id private long id; @column( unique = true, nullable = false ) private string name; ===== kitten.java ===== @id private long id; @column( unique = true, nullable = false ) private string name; @onetoone(optional = false) private cat mother; //only 1 kid per mother ...

now want query cats restrictions , orderby kitten.

session.createcriteria(cat.class) .createalias(???? , "kitten") .add( restrictions.like( "kitten.name", "name_of_a_kitten" ) .addorder( order.asc( "kitten.name" ) ) .list();

first thought of using subqueries couldn't find solution ordering , subquerys aren't readable alias in eyes.

cat can't changed there no way alter bi-directionallity.

how can achive query?

btw. i'm using hibernate 4.2.

i think it's not possible accomplish requirement simple hibernate criteria query.

criteria api can "select" root entity , require cat root entity. unfortunately cat entity has not reference kitten, it's not possible bring together it.

from point of view, have 2 options:

1) hql

if not pinned criteria api, utilize hql.

final list<cat> cats = session.createquery("select c kitten k bring together k.mother c k.name=:name order k.name") .setparameter("name", "name_of_a_kitten").list();

2) extract cat kitten collection explicitly

select kitten collection

final list<kitten> kittens = session.createcriteria(kitten.class) .add(restrictions.like("name", "name_of_a_kitten")) .addorder(order.asc("name")) .list();

and transform cat collection, e.g. using lambda-j (ontoone relation not lazy,so cat loaded )

final list<cat> cats = extract(kittens, on(kitten.class).getmother());

subquery

as you've noted, using subquery not useful because of impossibility ordering kitten attributes

final detachedcriteria q = detachedcriteria.forclass(kitten.class) .createalias("mother", "c") .add(restrictions.like("name", "name_of_a_kitten")) .setprojection(projections.property("c.id")); final list<cat> cats = session.createcriteria(cat.class) .add(property.forname("id").in(q)).list(); //not possible order kitten attributes

java hibernate criteria hibernate-criteria