Incompatible types; found: interface java.util.List<java.lang.Object>, required: interface java.util.List<test.entity.Emp>

Question

I have the following class structure

public class Emp implements java.io.Serializable {

....

}

public interface EmployeeDAO  {

 public List<Emp> findAllEmployees();

}

public class EmployeeDAOImpl  implements EmployeeDAO {

    public List<Emp> findAllEmployees() {
        CriteriaQuery cq = getEntityManager().getCriteriaBuilder().createQuery();
        cq.select(cq.from(Emp.class));
        return getEntityManager().createQuery(cq).getResultList();
    }
...

}

---

Issue I am having is

return getEntityManager().createQuery(cq).getResultList();

The above line gives me the following error, what could be the reason for this?

incompatible types; found: interface java.util.List<java.lang.Object>, 
required: interface java.util.List<test.entity.Emp>

The same code works in other higher version of Java. My current JDK is 1.6

Answer 1

You didn't tell the CriteraQuery which type it will return.

public List<Emp> findAllEmployees() {
    CriteriaQuery<Emp> cq = getEntityManager().getCriteriaBuilder().createQuery(Emp.class);
    cq.select(cq.from(Emp.class));
    return getEntityManager().createQuery(cq).getResultList();
}