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Hibernate version: 3.1 and Hibernate Annotation

Mapping documents:

User:

@Entity
@Table(name = "USUARIO")
@javax.persistence.SequenceGenerator(name = "SEQ_USUARIO", sequenceName = "SEQ_USUARIO")
public class User extends BaseModel {

private Integer codigo;

@Id(generate = GeneratorType.SEQUENCE, generator = "SEQ_USUARIO")
@Column(name = "CD_USUARIO")
public Integer getCodigo() {
return codigo;
}

public void setCodigo(Integer codigo) {
this.codigo = codigo;
}

private List<Group> grupos;

@ManyToMany(cascade = { CascadeType.ALL, CascadeType.MERGE }, mappedBy = "usuarios")
public List<Group> getGrupos() {
return grupos;
}

public void setGrupos(List<Group> grupos) {
this.grupos = grupos;
}

}

Group:

@Entity
@Table(name = "GRUPO")
@javax.persistence.SequenceGenerator(name = "SEQ_GRUPO", sequenceName = "SEQ_GRUPO")
public class Group extends BaseModel {

private Integer codigo;

@Id(generate = GeneratorType.SEQUENCE, generator = "SEQ_GRUPO")
@Column(name = "CD_GRUPO")
public Integer getCodigo() {
return codigo;
}

public void setCodigo(Integer codigo) {
this.codigo = codigo;
}

private DSystem sistema;

@ManyToOne
@JoinColumn(name = "CD_SISTEMA")
public DSystem getSistema() {
return sistema;
}

public void setSistema(DSystem sistema) {
this.sistema = sistema;
}

private Collection<User> usuarios;

@ManyToMany(cascade = { CascadeType.ALL, CascadeType.MERGE })
@JoinTable(table = @Table(name = "GRUPO_USUARIO"), joinColumns = { @JoinColumn(name = "CD_GRUPO") }, inverseJoinColumns = { @JoinColumn(name = "CD_USUARIO") })
public Collection<User> getUsuarios() {
return usuarios;
}

public void setUsuarios(Collection<User> usuarios) {
this.usuarios = usuarios;
}

}

System:

@Entity
@Table(name = "SISTEMA")
@javax.persistence.SequenceGenerator(name = "SEQ_SISTEMA", sequenceName = "SEQ_SISTEMA")
public class DSystem extends BaseModel {

private Integer codigo;

@Id(generate = GeneratorType.SEQUENCE, generator = "SEQ_SISTEMA")
@Column(name = "CD_SISTEMA")
public Integer getCodigo() {
return codigo;
}

public void setCodigo(Integer codigo) {
this.codigo = codigo;
}

private String nome;

@Column(name = "NM_SISTEMA")
public String getNome() {
return nome;
}

public void setNome(String nome) {
this.nome = nome;
}

private List<Group> grupos;

@OneToMany(mappedBy = "sistema")
@JoinColumn(name = "CD_SISTEMA")
public List<Group> getGrupos() {
return grupos;
}

public void setGrupos(List<Group> grupos) {
this.grupos = grupos;
}

}



Code between sessionFactory.openSession() and session.close():

Full stack trace of any exception that occurs:

Name and version of the database you are using:

The generated SQL (show_sql=true):

Debug level Hibernate log excerpt:



Hi everyone,

I was writing a hql query and didn't finished because i have a question about manyToMany relationship.
I have 3 entities: User, Group and System.
User have a collection of Groups and Group have a collection of Users (Here is the ManyToMany relationship), and Group have a System (ManyToOne relationship).

So, I want to write a query to retrieve all users that are in some group that is part of one System.

Does anyone know how to help me?

I find trying to write a query to do 3 tier searches all at one time to be too troublesome.

Find the system. Get the correct group from the system. Load the users for that group.