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hibenrate(8)一对一对象关系

发布时间: 2012-10-08 19:54:56 作者: rapoo

hibenrate(八)一对一对象关系
一、一对一单/双向外键关联(Annotation)
Annotation: @OneToOne @JoinColumn(name="")
XML:<many-to-one unique(单向)
<many-to-one unique <one-to-one property-ref(双向)
a)Husband.java

@Entitypublic class Husband {private int id;private Wife wief.........@Id@GeneratedValuepublic int getId() {return id;}@OneToOne@JoinColumn(name="wifeId")public Wife getWife() {return wife;}..........}

b)Wife.java
@Entitypublic class Wife {private int id;……………            @Id@GeneratedValuepublic int getId() {return id;}        //双向关联时加入:         //  private Husband husband;        // @OneToOne(mappedBy="wife")         // public Husband getHusband(){              return husband;;          }………………….}




注:凡是双向关联,必设:mappedBy



二、一对一单/双向主键关联(Annotation) (不重要)有bug
Annotation: @OneToOne@PrimaryKeyJoinColumn

a)Husband.java Wife.java的设置一样
..............@OneToOne@PrimaryKeyJoinColumnpublic Wife getWife() {return wife;}...........

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