小编Pat*_*ski的帖子

我有一些hibernate @OneToMany映射的问题.就像这里一样

@Entity
@Table(name = "albums")
@SequenceGenerator(name = "ALBUMS_SEQ", sequenceName = "albums_seq", allocationSize = 1)
public class AlbumDs {

    @Id @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "ALBUMS_SEQ")
    private Integer id;
    private Integer ownerId;
    private String name;
    private String description;
    private Date created;
    @OneToMany(cascade = CascadeType.ALL) 
    @JoinColumn(name = "albumId", insertable = true, updatable = true)
    private Set<UserAlbumDs> users = new HashSet<UserAlbumDs>();

    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public Integer getOwnerId() { …

我有这样的实体:

@Entity
public class Album {

    private Integer id;
    private Integer ownerId;
    private String name;
    private String description;
    private Date created;
    @OneToMany @JoinColumn(name = "albumId")
    private Set<AlbumUser> users = new HashSet<AlbumUser>();
    @OneToMany @JoinColumn(name = "albumId")
    private Set<Picture> pictures = new HashSet<Picture>();
}

另一个:

@Entity
public class Picture {

    private Integer id;
    private Integer creatorId;
    private Integer albumId;
    private Date created;
    private String title;
    private String description; 
    @ManyToOne @JoinColumn(name = "eventId")
    private Event event;
}

使用Criteria API我希望获得具有过滤的Picturs集的唯一AlbumD.我尝试这样的事情:

public Album read(Integer albumId, …