Java Persistence API

Named Queries

An entity may declare named queries, using the @NamedQuery annotation

@NamedQuery Annotation Example

  @Entity
  @NamedQuery(name="employeeBySsn" query="select e from Employee e where e.ssn = :ssn")
  public class Employee {
    ...
  }

  public class EmployeeDao {
    ...
    public Employee getEmployeeBySsn( String ssn ) {
      Query query = entityManager.getNamedQuery( "employeeBySsn" );
      query.setParameter( "ssn", ssn );
      return ( Employee )query.getSingleResult();
    }
    ...
  }

Multiple named queries can be defined by using the @NamedQueries annotation

@NamedQueries Annotation Example