How to use XML configuration for named queries in Spring data JPA?

Question

As per the Documentation we can specify named queries in an XML. But it does not tell how to use it in the code. Can someone please help?

Answer 1

say you have defined the `Named Query` as `application.myquery` in XML file.

In service/dao layer

List results = em.createNamedQuery("application.myquery")
    .setParameter("username", "blah")
    .setParameter("password","blahblahblah")
    .getResultList();

The orm file need to be included inside persistence.xml and the same should reside at META-INF/persistence.xml.

<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0">

  <persistence-unit name="myUnit" transaction-type="RESOURCE_LOCAL">
    <mapping-file>META-INF/orm.xml</mapping-file>
    <exclude-unlisted-classes/>
  </persistence-unit>

</persistence>

Refer this for more info.

Answer 2

As is mentioned by the lead developer of Spring Data JPA here, all you need to do (if you are using a version newer or equal to Spring Data JPA 1.5 - I tested with 1.6.1.RELEASE) is add a method in the repository with the same name as the query.

For example you could have code like:

    @Entity
    @NamedQuery(name = "User.findByLastname", query="select u from User u where u.lastname = ?1")
    public class User {
       //whatever
    }

If you don't want to use annotations but prefer XML instead, you need to add

<named-query name="User.findByLastname">
  <query>select u from User u where u.lastname = ?1</query>
</named-query>

to orm.xml like is shown here

Finally the repository would look like

public interface UserRepository extends CrudRepository<User, Long> {

  @Query
  List<User> findByLastname(String lastname);
}

Answer 3

META-INF/orm.xml

<?xml version="1.0" encoding="UTF-8"?>
<entity-mappings xmlns="http://java.sun.com/xml/ns/persistence/orm"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm_2_0.xsd"
    version="2.0">

    <named-query name="Role.findByCond">
        <query>from Role where rid = ?1 and rname = ?2</query>
    </named-query>

</entity-mappings>

RoleRepository.java

@Query
List<Role> findByCond(String rid, String rname);