Package org.hibernate.query.criteria

Class CriteriaDefinition<R>

  • Type Parameters:
    R - the query result type
    All Implemented Interfaces:
    AbstractQuery<R>, CommonAbstractCriteria, CriteriaBuilder, CriteriaQuery<R>, Serializable, HibernateCriteriaBuilder, JpaCriteriaBase, JpaCriteriaNode, JpaCriteriaQuery<R>, JpaCteContainer, JpaQueryableCriteria<R>, JpaSelectCriteria<R>
    @Incubating
public abstract class CriteriaDefinition<R>
extends HibernateCriteriaBuilderDelegate
implements JpaCriteriaQuery<R>
    A utility class that makes it easier to build criteria queries. From within an initializer block of a (usually anonymous) subclass, all operations of the CriteriaBuilder and CriteriaQuery may be called without the need for specifying the target object.

    For example: 

     sessionFactory.inTransaction(session -> {
     List<Book> books
             = new CriteriaDefinition<>(sessionFactory, Book.class) {{
                 var book = from(Book.class);
                 where(like(book.get(Book_.title), "%Hibernate%"));
                 orderBy(desc(book.get(Book_.publicationDate)), asc(book.get(Book_.isbn)));
                 book.fetch(Book_.authors);
             }}
             .createSelectionQuery(session)
             .setMaxResults(10)
             .getResultList();
     ...
 });

    A CriteriaDefinition may even be used to modify a base HQL or criteria query: 

     sessionFactory.inTransaction(session -> {
     List<Book> books
             = new CriteriaDefinition<>(sessionFactory, Book.class,
                     "from Book left join fetch authors where type = BOOK") {{
                 var book = (JpaRoot<Book>) getSelection();
                 where(getRestriction(), like(book.get(Book_.title), "%Hibernate%"));
                 orderBy(desc(book.get(Book_.publicationDate)), asc(book.get(Book_.isbn)));
             }}
             .createSelectionQuery(session)
             .getResultList();
     ...
 });
    For queries which don't change between executions, the CriteriaDefinition may be safely built and cached at startup: 
     // build and cache the query
 static final CriteriaQuery<Book> bookQuery =
         new CriteriaDefinition<>(sessionFactory, Book.class) {{
             var book = from(Book.class);
             where(like(book.get(Book_.title), "%Hibernate%"));
             orderBy(desc(book.get(Book_.publicationDate)), asc(book.get(Book_.isbn)));
             book.fetch(Book_.authors);
         }};

 ...

 // execute it in a session
 sessionFactory.inTransaction(session -> {
     List<Book> books =
             session.createQuery(bookQuery)
                     .setMaxResults(10)
                     .getResultList();
     ...
 });
    Since:
    6.3
    See Also:
    Serialized Form