Mybatis 一对多(OneToOne)关系映射

CREATE TABLE t_customer( 
  id int(10) not null auto_increment, 
  address varchar(120), 
  postcode varchar(6), 
  sex varchar(2), 
  cname varchar(24), 
  primary key(id) 
)charset="GB2312"; 

CREATE TABLE t_orders( 
  id int(10) not null auto_increment, 
  code varchar(24), 
  customer_id int(3) not null, 
  primary key(id) 
)charset="GB2312";

ALTER TABLE t_orders 
ADD CONSTRAINT orders_customer_fk FOREIGN KEY (customer_id) REFERENCES t_customer(id)

-- t_orders.customer_id 参照 t_customer.id

package com.lixing.ibatis.entity.onetomany; 

import java.io.Serializable; 
import java.util.List; 

public class Customer implements Serializable{ 
  private static final long serialVersionUID = 451949797460417653L; 
  private int id; 
  private String address; 
  private String postcode; 
  private String sex; 
  private String cname; 
  private List<Orders> orders;   //一个Customer 对应N多个Orders

  public int getId() { 
    return id; 
  } 
  public void setId(int id) { 
    this.id = id; 
  } 
  public String getAddress() { 
    return address; 
  } 
  public void setAddress(String address) { 
    this.address = address; 
  } 
  public String getPostcode() { 
    return postcode; 
  } 
  public void setPostcode(String postcode) { 
    this.postcode = postcode; 
  } 
  public String getSex() { 
    return sex; 
  } 
  public void setSex(String sex) { 
    this.sex = sex; 
  } 
  public String getCname() { 
    return cname; 
  } 
  public void setCname(String cname) { 
    this.cname = cname; 
  } 
  public List<Orders> getOrders() { 
    return orders; 
  } 
  public void setOrders(List<Orders> orders) { 
    this.orders = orders; 
  } 
} 

package com.lixing.ibatis.test; 

import java.util.Iterator; 
import java.util.List; 

import org.apache.ibatis.session.SqlSession; 
import org.apache.ibatis.session.SqlSessionFactory; 
import org.junit.After; 
import org.junit.Before; 
import org.junit.Test; 

import com.lixing.ibatis.entity.onetomany.Customer; 
import com.lixing.ibatis.entity.onetomany.Orders; 
import com.lixing.ibatis.onetomany.mapper.CustomerMapper; 
import com.lixing.ibatis.onetomany.mapper.OrdersMapper; 
import com.lixing.ibatis.util.MyBatisUtil; 


public class OrdersMapperTest { 
  private SqlSessionFactory sqlSessionFactory=null; 
  private SqlSession session=null; 
    
  @Before 
  public void before(){ 
    sqlSessionFactory=MyBatisUtil.getInstance(); 
    session=sqlSessionFactory.openSession(); 
  } 
    
  @Test 
  public void testInsertOrders(){ 
    Orders orders=new Orders(); 
    orders.setCode("code__1"); 
    orders.setCustomerId(1); 
     
    OrdersMapper ordersMapper=session.getMapper(OrdersMapper.class); 
    ordersMapper.insertOrders(orders); 
    session.commit();     
  } 
    
  @Test 
  public void testInsertCustomerOneToMany(){ 
    Customer customer=new Customer(); 
    customer.setCname("Lixing5"); 
    customer.setPostcode("518105"); 
    customer.setSex("男"); 
    customer.setAddress("广东省深圳市5"); 
     
    CustomerMapper customerMapper=session.getMapper(CustomerMapper.class); 
    customerMapper.insertCustomer(customer); 
    System.out.println(customer.getId()); 
     
    Orders orders1=new Orders(); 
    orders1.setCode("code__5_1"); 
    orders1.setCustomerId(customer.getId()); 
     
    Orders orders2=new Orders(); 
    orders2.setCode("code__5_2"); 
    orders2.setCustomerId(customer.getId()); 
     
    Orders orders3=new Orders(); 
    orders3.setCode("code__5_3"); 
    orders3.setCustomerId(customer.getId()); 
     
    OrdersMapper ordersMapper=session.getMapper(OrdersMapper.class); 
    ordersMapper.insertOrders(orders1); 
    ordersMapper.insertOrders(orders2); 
    ordersMapper.insertOrders(orders3); 
     
    session.commit();    
  } 
    
     
  @Test 
  public void testGetOrdersManyToOne(){ 
    OrdersMapper ordersMapper=session.getMapper(OrdersMapper.class); 
    List<Orders> list=ordersMapper.getOrdersById(5); 
    for(int i=0;i<list.size();i++){ 
      Orders orders=list.get(i); 
      Customer customer=orders.getCustomer(); 
      System.out.println(orders.getId()+"\t"+orders.getCode()+"\t"+orders.getCustomerId()); 
      System.out.println("\t \t--:"+customer.getId()+"\t"+customer.getCname()); 
    }     
    session.commit(); 
  } 
    
    
  @Test 
  public void testGetCustomerOneToMany(){ 
    CustomerMapper customerMapper=session.getMapper(CustomerMapper.class); 
    Customer customer=customerMapper.getCustomer(5); 
    List<Orders> orders=customer.getOrders(); 
    System.out.println(customer.getId()+"\t"+customer.getCname()+"\t"+customer.getPostcode()+"\t"+customer.getAddress()); 
    for(int i=0;i<orders.size();i++){ 
      Orders order=orders.get(i); 
      System.out.println("\t \t --:"+order.getId()+"\t"+order.getCode()+"\t"+order.getCustomerId()); 
    } 
    session.commit(); 
  } 
    
  @After 
  public void after(){ 
    session.close(); 
  } 
}