hibernate 一对一双向关联_外键

这种情况是多对一的特例，即外键不准重复。

 

 

1.单向一对一

Person类：

package com.bjpowernode.hibernate.domain;
public class Person {
	private int id;
	private String name;
	private IdCard idCard;
	
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public IdCard getIdCard() {
		return idCard;
	}
	public void setIdCard(IdCard idCard) {
		this.idCard = idCard;
	}
}

 

Person配置文件：

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>

	<class name="com.bjpowernode.hibernate.domain.Person" table="t_person">
		<id name="id">
			<generator class="native"/>
		</id>
		
		<property name="name"/>
		
		<many-to-one name="idCard" unique="true"/>
		
	
	</class>
	
</hibernate-mapping>

 

 

 

 

 

IdCard类：

package com.bjpowernode.hibernate.domain;



public class IdCard {
	private int id;
	private String name;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	/*public Set getStudents() {
		return students;
	}
	public void setStudents(Set students) {
		this.students = students;
	}*/
	
	
}

 

IdCard配置文件：

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>

	<class name="com.bjpowernode.hibernate.domain.IdCard" table="t_idcard">
		<id name="id">
			<generator class="native"/>
		</id>
		
		<property name="name"/>
		
	
	</class>
	
</hibernate-mapping>

 

 

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2.双向一对一

 

Person类和配置文件完全一样，这里不再添加。

 

IdCard中添加一个Person的引用。

package com.bjpowernode.hibernate.domain;



public class IdCard {
	private int id;
	private String name;
	private Person person;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	/*public Set getStudents() {
		return students;
	}
	public void setStudents(Set students) {
		this.students = students;
	}*/
	public Person getPerson() {
		return person;
	}
	public void setPerson(Person person) {
		this.person = person;
	}
	
	
}

 

 

IdCard配置文件：

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>

	<class name="com.bjpowernode.hibernate.domain.IdCard" table="t_idcard">
		<id name="id">
			<generator class="native"/>
		</id>
		
		<property name="name"/>
		
		<one-to-one name="person" property-ref="idCard"/>
	
	</class>
	
</hibernate-mapping>

 

至此，双向一对一，外键策略完成。