Using Hibernate Criteria

[Hanna Habashy]

If I have a class like this:

class User2Book
{
long id;
String category;
Book book;

}

    

How can I create a criteria on this class that return a list of books only filtered by category?
P.S. I simplified the example I have to work with.

Thanks,

[Mansi Mishra]

Try this...

   
DetachedCriteria criteria = DetachedCriteria.forClass(User2Book.class);
getHibernateTemplate.findByCriteria(criteria).add(Restrictions.eq("category", filterValue))
 

[Hanna Habashy]

Mansi Mishra. wrote:Try this...

   
DetachedCriteria criteria = DetachedCriteria.forClass(User2Book.class);
getHibernateTemplate.findByCriteria(criteria).add(Restrictions.eq("category", filterValue))
 

Can you elaborate on how this code going to return a list of books?

Thanks,

[Mansi Mishra]

Hanna Habashy wrote:

Mansi Mishra. wrote:Try this...

Can you elaborate on how this code going to return a list of books?

Thanks,

getHibernateTemplate.findByCriteria(criteria).add(Restrictions.eq("category", filterValue))

returns a list of User2Book objects filtered by "category" using the "filterValue"
All you need to do is fetch this into an arraylist of the same type

   
List<User2Book> books = (List<User2Book>)getHibernateTemplate.findByCriteria(criteria).add(Restrictions.eq("category", filterValue));
 

returns a list of User2Book objects.

[Hanna Habashy]

Mansi Mishra. wrote:

Hanna Habashy wrote:

Mansi Mishra. wrote:Try this...

Can you elaborate on how this code going to return a list of books?

Thanks,

getHibernateTemplate.findByCriteria(criteria).add(Restrictions.eq("category", filterValue))

returns a list of User2Book objects filtered by "category" using the "filterValue"
All you need to do is fetch this into an arraylist of the same type

   
List<User2Book> books = (List<User2Book>)getHibernateTemplate.findByCriteria(criteria).add(Restrictions.eq("category", filterValue));
 

returns a list of User2Book objects.

Thanks for the response, but my question is how to return a list of books, not a list of User2Book.

[stanislav bashkirtsev]

http://docs.jboss.org/hibernate/stable/core/reference/en/html/querycriteria.html

[Mansi Mishra]

Oh okay...
Then may be you could try using projections. That should let you fetch a list of books.

[Hanna Habashy]

Thanks, I get it solved.

criteria = createCriteria(User2Book.class, "u2b")
crit.add(Restrictions.eq("u2p.category", value));
crit.setProjection(Property.forName("book"));
crit = crit.createCriteria("user");