【hibernate框架】一对一单向主键关联(Annotation实现)

单项主键关联指的是：husband和wife之间有关联关联的。但是是用主键做关联的，说白了就是husband的id会参考wife的id(husband的id是1，n那么它所对应的wife的id也是1)。

Husband.java:

package cn.edu.hpu.one2one;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.JoinColumn;import javax.persistence.OneToOne;import javax.persistence.PrimaryKeyJoinColumn;@Entitypublic class Husband {private int id;private String name;private Wife wife;@Id@GeneratedValuepublic int getId() {return id;}public void setId(int id) {this.id = id;}@OneToOne//@JoinColumn(name="wifeid")@PrimaryKeyJoinColumn //用主键做连接的一种东西public Wife getWife() {return wife;}public void setWife(Wife wife) {this.wife = wife;}public String getName() {return name;}public void setName(String name) {this.name = name;}}

wife.java:

package cn.edu.hpu.one2one;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.OneToOne;@Entitypublic class Wife {private int id;private String name;private Husband husband;@Id@GeneratedValuepublic int getId() {return id;}public void setId(int id) {this.id = id;}@OneToOne(mappedBy="wife")public Husband getHusband() {return husband;}public void setHusband(Husband husband) {this.husband = husband;}public String getName() {return name;}public void setName(String name) {this.name = name;}}

生成的建表语句：
 create table Husband (
        id integer not null auto_increment,
        name varchar(255),
        primary key (id)
    )


    create table Wife (
        id integer not null auto_increment,
        name varchar(255),
        primary key (id)
    )


    alter table Husband 
        add index FKAEEA401BF5211E1C (id), 
        add constraint FKAEEA401BF5211E1C 
        foreign key (id) 
        references Wife (id)
schema export complete
可以看见Wife和Husband表里面没有外键的字段，但是两个主键之间会设关联。
(看数据库的图形化界面，你也会看到husband的id字段上有小钥匙的图标，这就是一个主键关联)