多元查询jdo无主关系

Question

我需要一些帮助

我正在使用gae，datastore和jdo

国家1 - N部门;部门1 - N省，无主关系，知道省的国家数据

实体派：

@PersistenceCapable(detachable = "true")
public class Pais implements Serializable{
    /**
     * 
     */
    private static final long serialVersionUID = -4204342672595368670L;
    @PrimaryKey
    @Persistent
    private String idPais;
    @Persistent
    private String codigo;
    @Persistent
    private String descripcion;
    @Persistent
    private Long version;
    @NotPersistent
    private String operacion;   
    @NotPersistent
    private String codePais;

实体Departamento：

@PersistenceCapable(detachable = "true")
public class Departamento implements Serializable{
    private static final long serialVersionUID = 2029238048901900816L;
    @PrimaryKey
    @Persistent
    private String idDepartamento;
    @Persistent
    private String codigo;
    @Persistent
    private String descripcion;
    @Persistent
    private Long version;
    @Persistent
    @Unowned
    private Pais beanPais;
    @Persistent
    private String codePais;
    @NotPersistent
    private String operacion;
    @NotPersistent
    private String codeDepartamento;

Entity Provincia

@PersistenceCapable(detachable = "true")
public class Provincia implements Serializable{
    /**
     * 
     */
    private static final long serialVersionUID = -2560617366920790922L;
    @PrimaryKey
    @Persistent
    private String idProvincia;
    @Persistent
    private String codigo;
    @Persistent
    private String descripcion;
    @Persistent
    private Long version;
    @NotPersistent
    private String operacion;
    @NotPersistent
    private String codeProvincia;
    @Persistent
    private String codeDepartamento;
    @Persistent
    @Unowned
    private Departamento beanDepartamento;
    @NotPersistent
    private String codePais;

查询允许我查看国家/地区数据，访问分区 JDO