spring data jpa how implement interface query method in dao interface

[wilson]

hi,all,

@Query("from Staff where cardNo = :cardNo")
    public Staff findByCardNo(@Param("cardNo") String cardNo);

but when I want to implement search method by a search criteria,how I to write the @Query("").I want to implement interface query methods in dao interface.
thanks for help.

[Marten Deinum]

I suggest a read of the spring-data-jpa reference guide... If you use @Query spring-data will generate the query for you if you want your own implementation don't use @Query but provide your own implementation (all that is explained in the reference guide).

[wilson]

I suggest a read of the spring-data-jpa reference guide... If you use @Query spring-data will generate the query for you if you want your own implementation don't use @Query but provide your own implementation (all that is explained in the reference guide).

thanks a lot!
like follows:
class Depart{
private int id;
}
class Staff{
@ManyToMany()
private List<Department> departments;
}

in daoImpl package:
class StaffDaoImpl implements StaffDao{
public List<Staff> findByDepartment(Long departmentId){
Query query=em.createQuery("select staff from Staff staff left join fetch staff.departments d where d.id = :departmentId");
query.setParameters("departmentId",departmentId);
return query.getResultList();

and now I want to use CriteriaBuilder implement "left join fetch staff.departments d where d.id = :departmentId",

please help,thanks!