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I have following dao method:
@Override
public List<AdminRole> findAll() {
Session session = sessionFactory.getCurrentSession();
Criteria criteria = session.createCriteria(AdminRole.class);
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
return criteria.list();
}
Actually I want to retrieve all entries from database.
Sometimes I see duplicates. This happens when I add user with AdminRole.
I have read that it is possible when I use EAGER fetch type and this should be fix adding following line:
criteria.setResultTransformer(Criteria.DISTINCT_ROOT_ENTITY);
But this doesn’t help me.
my mapping:
@Entity
@Table(name = "terminal_admin_role")
public class AdminRole {
@Id
@Column(name = "role_id", nullable = false, unique = true)
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "user_id")
@SequenceGenerator(name = "user_id", sequenceName = "user_id")
private Long adminId;
@Column(name = "role")
private String role;
public AdminRole(String role) {
this.role = role;
}
public AdminRole() {
}
// get set
@Override
public String toString(){
return role;
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (!(o instanceof AdminRole)) {
return false;
}
AdminRole adminRole = (AdminRole) o;
if (!role.equals(adminRole.role)) {
return false;
}
return true;
}
@Override
public int hashCode() {
return role.hashCode();
}
}
and
@Entity
@Table(name = "terminal_admin")
public class TerminalAdmin {
@ManyToMany(fetch=FetchType.EAGER,cascade=CascadeType.ALL)
@JoinTable(name = "admin_role", joinColumns = {
@JoinColumn(name = "admin_id", nullable = false) },
inverseJoinColumns = { @JoinColumn(name = "role_id",
nullable = false) })
private Set<AdminRole> adminRoles;
//...
}
P.S.
I cannot switch fetch type.
I don’t want to put this list into set.
Answer
There is no reason to use DISTINCT_ROOT_ENTITY or anything similar, all you need is:
session.createCriteria(AdminRole.class).list();
If you get duplicates, then you really have them in the database. Check the code which saves AdminRoles either directly or by cascading from other entities.
When cascading PERSIST/MERGE operations from other entities, make sure that the operation is cascaded to a persistent/detached AdminRole instance, not to a transient (new) one.