Named Query in hibernate & Hibernate Example 6

    1)     To consolidate all the queries of an Entity class. Putting all queries as annotations
          at Entity level.

    2)     To write queries at Entity level

@NamedQuery(name, actual query)

@NamedNativeQuery(name,actual SQL query)

In NamedNativeQuery , we can actually provide SQL type query as an argument.

HibernateNamedQuery.java

public class HibernateNamedQuery {

     public static void main(String[] args) {

          

         SessionFactory sessionFactory = new                                     Configuration().configure().buildSessionFactory();

           Session session = sessionFactory.openSession();

           session.beginTransaction();

          

           Query query = session.getNamedQuery("Person.byId");

           query.setLong(0,5);

           List<Person> list = (List<Person>) query.list();

           for(Person p: list)

                System.out.println(p.getName());

           Query query1 = session.getNamedQuery("Person.byName");

           query1.setString(0,"Person 1");

           List<Person> list1 = (List<Person>) query1.list();

           for(Person p: list1)

                System.out.println(p.getName());

          

           session.getTransaction().commit();

           session.close();

     }

}

Person.java

@Entity(name="PERSON")

@NamedQuery(name="Person.byId",query="from PERSON where id=?")

@NamedNativeQuery(name="Person.byName",query="Select * from Person where Name=?",resultClass=Person.class)

public class Person implements java.io.Serializable{

      private static final long serialVersionUID = 1L;

      private String name;

     

      @Id

      @GeneratedValue(strategy=GenerationType.AUTO)

      private long id;

      public String getName() {

            return name;

      }

      public void setName(String name) {

            this.name = name;

      }

      public long getId() {

            return id;

      }

      public void setId(long id) {

            this.id = id;

      }

}

Output:

Hibernate: select person0_.id as id0_, person0_.name as name0_ from PERSON person0_ where person0_.id=?

Person 5

Hibernate: Select * from Person where Name=?

Person 1