Hibernate：單個表中的多個@ManyToMany關系

Question

我有一個項目，其中Hibernate用於管理實體。 兩個表之間可以存在多個@ManyToMany關系。 所以基本上我有這樣的代碼：

@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@JoinTable(name = "movies_screenplay_authors",
        joinColumns = @JoinColumn(name = "movie_id", nullable = false, updatable = false),
        inverseJoinColumns = @JoinColumn(name = "staff_id", nullable = false, updatable = false))
private Set<Staff> screenplayAuthors = Sets.newHashSet();

@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@JoinTable(name = "movies_story_authors",
        joinColumns = @JoinColumn(name = "movie_id", nullable = false, updatable = false),
        inverseJoinColumns = @JoinColumn(name = "staff_id", nullable = false, updatable = false))
private Set<Staff> storyAuthors = Sets.newHashSet();

現在，我想將這些關系存儲在單個表中，並附加一些描述關系類型的列。 所以基本上，我想有這樣的東西（使用偽代碼）：

@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@JoinTable(name = "movies_staff",
        joinColumns = @JoinColumn(name = "movie_id", nullable = false, updatable = false),
        inverseJoinColumns = @JoinColumn(name = "staff_id", nullable = false, updatable = false),
        joinCriteria = @JoinCriteria(columnName = "staff_type", value = StaffType.SCREENPLAY_AUTHOR, enumType = EnumType.STRING))
private Set<Staff> screenplayAuthors = Sets.newHashSet();

@ManyToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
@JoinTable(name = "movies_staff",
        joinColumns = @JoinColumn(name = "movie_id", nullable = false, updatable = false),
        inverseJoinColumns = @JoinColumn(name = "staff_id", nullable = false, updatable = false),
        joinCriteria = @JoinCriteria(columnName = "staff_type", value = StaffType.STORY_AUTHOR, enumType = EnumType.STRING))
private Set<Staff> storyAuthors = Sets.newHashSet();

這在Hibernate或Java世界的任何地方都是可能的嗎？

Answer 1

您可以在每個@JoinTable注釋之后添加如下內容：

@Fetch(FetchMode.SUBSELECT)

這一切。