This is my situation, I have two basic POJO's which I've given a simple hibernate mapping :
Person
- PersonId
- Name
- Books
Book
- Code
- Description
My SQL Query returns rows that look like this :
PERSONID NAME CODE DESCRIPTION
-------- ---------- ---- -----------
1 BEN 1234 BOOK 1
1 BEN 5678 BOOK 2
2 JOHN 9012 BOOK 3
My hibernate query looks like this :
session.createSQLQuery("select personid, name, code, description from person_books")
.addEntity("person", Person.class)
.addJoin("book", "person.books")
.list();
This is per section : 18.1.3 of the hibernate documentation : http://docs.jboss.org/hibernate/core/3.6/reference/en-US/html/querysql.html#d0e17464
What I expect to get in my list is 2 Person Objects with the contained book objects in the collection of books :
List
|- Ben
| |- Book 1
| '- Book 2
'- John
'- Book 3
What I am actually seeing is this :
List
|- Object[]
| |- Ben
| | |- Book 1
| | '- Book 2
| '- Book 1
|- Object[]
| |- Ben
| | |- Book 1
| | '- Book 2
| '- Book 2
'- Object[]
|- John
| '- Book 3
'- Book 3
Does anyone know if it's possible to get what I want using this method?
Expanding on Mathews answer. To force hibernate to only return a list of persons do:
List<Person> peopleWithBooks = session.createSQLQuery(
"select {p.*}, {b.*} from person p, book b where <complicated join>").
.addEntity("p", Person.class)
.addJoin("b", "p.books")
.addEntity("p", Person.class)
.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY)
.list();
Associated Book entities will be fetched and initialized without a additional call to the db.
The duplicate
.addEntity("p", Person.class)
is necessary because
.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY)
operates on the last entity added.