一对一双向外键关联(Annotation方法): 一夫(Husband)一妻(Wife)的一对一双向外键关联 Husband和Wife实体类：

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;@Entitypublic class Husband {	private int id;	private String name;	private Wife wife;	@Id	@GeneratedValue	public int getId() {		return id;	}	public void setId(int id) {		this.id = id;	}		@OneToOne	@JoinColumn(name="wifeid")	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;	}		}

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	@GeneratedValue	public int getId() {		return id;	}	public void setId(int id) {		this.id = id;	}		@OneToOne	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： alter table Husband          drop          foreign key FKAEEA401BC6294CED     alter table Wife          drop          foreign key FK29233185D75BEA     drop table if exists Husband     drop table if exists Wife     create table Husband (         id integer not null auto_increment,         name varchar(255),         wifeid integer,         primary key (id)     )     create table Wife (         id integer not null auto_increment,         name varchar(255),         husband_id integer,         primary key (id)     )     alter table Husband          add index FKAEEA401BC6294CED (wifeid),          add constraint FKAEEA401BC6294CED          foreign key (wifeid)          references Wife (id)     alter table Wife          add index FK29233185D75BEA (husband_id),          add constraint FK29233185D75BEA          foreign key (husband_id)          references Husband (id) 双向关联在数据库中只需一边设置外键就行了,所以wife的husband_id就可以不要 mappedBy="wife"告诉hibernate，Wife和husband之间是一个1对1的关联， 对方husband类的wife属性已经做映射了,你就不用管我生成的外键的关联了 对方那边是主导，你不用管我这边的设置 这个时候wife建表语句中就没有husband_id属性了 凡是双向关联必设mappedBy 所以wife实体类注解写成： @OneToOne(mappedBy="wife") public Husband getHusband() { return husband; }

生成的表中wife就没有husband_id字段了

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