一 關聯映射類型
1．多對一(Employee - Department)
多對一關聯是一個部門可以有多個員工
所用到的映射文件為：
<many-to-one name="depart" column="depart_id"/>
二 代碼分析
1．首先創建兩個類，Department和Employee，並把他們關聯起來
（1）Department類
package com.hbsi.domain;
//部門類
public class Department {
private int id;
private String name;
public Department() {
super();
// TODO Auto-generated constructor stub
}
public Department(int id, String name) {
super();
this.id = id;
this.name = name;
}
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 String toString() {
return "Department [id=" + id + ", name=" + name + "]";
}
}
（2）Employee類
package com.hbsi.domain;
//員工類 一般主鍵是建在多的一方
public class Employee {
private int id;
private String name;
// 得到的是一個 對象，可以得到員工對應的部門的詳細信息
private Department depart;
public Employee() {
super();
// TODO Auto-generated constructor stub
}
public Employee(int id, String name, Department depart) {
super();
this.id = id;
this.name = name;
this.depart = depart;
}
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 Department getDepart() {
return depart;
}
public void setDepart(Department depart) {
this.depart = depart;
}
public String toString() {
return "Employee [id=" + id + ", name=" + name + ", depart=" + depart
+ "]";
}
}
注：之所以在員工表中設主鍵是為了減少資源消耗，而如果設置
private int depart_id;
通過員工查找部門的話，只能找到部門的id,得不到部門的其他信息 ，
設置的Deparment的類對象作為外鍵，可以得到部門的所有信息
