以Student与StuIDCard一对一双向关联为例，说一下用XML实现两者的一对一双向关联。
学生与学生证之间的关联关系。
Student.java:
package cn.edu.hpu.model;
public class Student {
private int id;
private String name;
private int age;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
StudentIdCard.java:
package cn.edu.hpu.model;
public class StuIDCard {
private int id;
private String num;
private Student student;//与学生实体类单向关联
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getNum() {
return num;
}
public void setNum(String num) {
this.num = num;
}
public Student getStudent() {
return student;
}
public void setStudent(Student student) {
this.student = student;
}
}
Student.hbm.xml:
<pre name="code" class="html"><?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping package="cn.edu.hpu.model">
<class name="Student" table="student" dynamic-update="true">
<id name="id" column="id">
<generator class="native"></generator>
</id>
<property name="name"></property>
<property name="age"></property>
<one-to-one name="stuIDCard" property-ref="student"></one-to-one>
</class>
</hibernate-mapping>
StuIDCard.hbm.xml:
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="cn.edu.hpu.model.StuIDCard">
<id name="id">
<generator class="native"></generator>
</id>
<property name="num"/>
<!-- 站在当前类的立场考虑，设外键关联的时候设置的 many-to-one-->
<!-- many-to-one多个学生证对应一个学生 unique="true"唯一为true，必须保证id唯一，就变成了一对一-->
<!--column定义哪个字段做为外键关联类字段-->
<many-to-one name="student" column="id" unique="true"></many-to-one>
</class>
</hibernate-mapping>
