hibernate实现一对一关系映射(基于主键)_hibernate 一对一关系实现-优快云博客

本文链接：https://blog.youkuaiyun.com/qq_22498277/article/details/51472890

本文介绍了一对一关联映射在Hibernate中的实现方式，包括Department和Manager两个类的定义及其相互间的一对一关联关系，并展示了如何通过XML配置文件进行一对一关联的映射。

Department类：

package cn.lfd.hibernate.n21.one2one;
public class Department {
	private Integer deptID;
	private String deptName;
	private Manager mgr;
	public Integer getDeptID() {
		return deptID;
	}
	public void setDeptID(Integer deptID) {
		this.deptID = deptID;
	}
	public String getDeptName() {
		return deptName;
	}
	public void setDeptName(String deptName) {
		this.deptName = deptName;
	}
	public Manager getMgr() {
		return mgr;
	}
	public void setMgr(Manager mgr) {
		this.mgr = mgr;
	}
	
}

Manager类:

package cn.lfd.hibernate.n21.one2one;
public class Manager {
	private Integer mgrId;
	private String mgrName;
	private Department dept;
	public Integer getMgrId() {
		return mgrId;
	}
	public void setMgrId(Integer mgrId) {
		this.mgrId = mgrId;
	}
	public String getMgrName() {
		return mgrName;
	}
	public void setMgrName(String mgrName) {
		this.mgrName = mgrName;
	}
	public Department getDept() {
		return dept;
	}
	public void setDept(Department dept) {
		this.dept = dept;
	}
	
}

Manaeger.hbm.xml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">
<!-- Generated 2014-9-29 8:46:32 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping package="cn.lfd.hibernate.n21.one2one">
    <class name="Manager" table="MANAGERS">
        <id name="mgrId" type="java.lang.Integer">
            <column name="MGR_ID" />
            <generator class="native" />
        </id>
        <property name="mgrName" type="java.lang.String">
            <column name="MGR_NAME" length="40"/>
        </property>
        
      <one-to-one name="dept" class="Department">
      </one-to-one>
    </class>
</hibernate-mapping>

Department.hbm.xml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">
<!-- Generated 2014-9-29 8:46:32 by Hibernate Tools 3.4.0.CR1 -->
<hibernate-mapping package="cn.lfd.hibernate.n21.one2one">
    <class name="Department" table="DEPARTMENTS">
        <id name="deptID" type="java.lang.Integer">
            <column name="DEPT_ID" />
            <generator class="foreign">
            	<param name="property">mgr</param>
            </generator>
        </id>
        <property name="deptName" type="java.lang.String">
            <column name="DEPT_NAME"/>
        </property>
        
        <!-- 映射一对一的关系  constrained="true"给当前主键添加外键约束-->
        <one-to-one name="mgr" class="Manager" constrained="true"></one-to-one>
    </class>
</hibernate-mapping>