//銷售單對(duì)象
public class SaleBill {
    private Long id;
    private String sn;
    private Set<</span>SaleBillItem> items = new HashSet<</span>SaleBillItem>();
    //getter & setter
}  
        
//銷售單明細(xì)對(duì)象
public class SaleBillItem {
    private Long id;
    private Double price;
    private SaleBill bill;
    //getter & setter
}

<mapper namespace="cd.itcast.mybatis.salebill.SaleBillMapper">
<!-- 保存SaleBill對(duì)象，該調(diào)用必須放在SaleBillItem對(duì)象保存之前 -->
    <insert id="saveSaleBill" keyProperty="id" parameterType="SaleBill"
                useGeneratedKeys="true">
                INSERT INTO salebill(sn) values (#{sn})
    </insert>
<!-- 保存SaleBillItem對(duì)象 -->
    <insert id="saveSaleBillItem" keyProperty="id" parameterType="SaleBillItem" useGeneratedKeys="true">
            INSERT INTO salebillitem(price,bill_id) values (#{price},#{bill.id})
</insert>
<!-- 內(nèi)嵌映射SaleBill對(duì)象，注意，因?yàn)槭墙M合關(guān)系，所以不會(huì)出現(xiàn)單獨(dú)去拿SaleBillItem對(duì)象的情況，所以只需要映射SaleBill主對(duì)象即可 -->
<resultMap type="SaleBill" id="salebillmap">
            <id property="id" column="id"/>
            <result column="sn" property="sn"/>
            <collection property="items" column="id" ofType="SaleBillItem" >
            <id column="item_id" property="id"/>
            <result column="item_price" property="price"/>
            <association property="bill" column="bill_id" resultMap="salebillmap" />
           </collection>
</resultMap>
 
<!-- 因?yàn)榱斜砗蛦为?dú)的get方法都是采用內(nèi)聯(lián)的查詢，所以把公用的SQL提取出來 -->
    <sql id="select">
            SELECT b.*,item.id as item_id,item.price as item_price FROM salebill b LEFT JOIN salebillitem item ON b.id = item.bill_id
     </sql>
 
<!-- get -->
    <select id="get" parameterType="long" resultMap="salebillmap">
            <include refid="select"/> WHERE b.id = #{id}
     </select>
 
<!-- 列表查詢 -->
    <select id="list" resultMap="salebillmap">
            <include refid="select"/>
     </select>
 
<!-- 刪除SaleBill對(duì)象 -->
    <delete id="delete" parameterType="long">
            DELETE FROM salebill WHERE id = #{id}      
    </delete>
 
<!-- 刪除SaleBill對(duì)象對(duì)應(yīng)的Item對(duì)象，注意，因?yàn)橛型怄I的約束，這條刪除語句應(yīng)該放在delete SaleBill之前執(zhí)行。注意，傳入的這個(gè)id應(yīng)該是SaleBill的id -->
    <delete id="deleteItems" parameterType="long">
     DELETE FROM salebillitem WHERE bill_id = #{id}
    </delete>
</mapper>

//先創(chuàng)建一個(gè)Mapper接口，使用接口來完成映射
public interface SaleBillMapper {
? ? void saveSaleBill(SaleBill sb);
? ? void saveSaleBillItem(SaleBillItem sbi);
? ? SaleBill get(Long id);
? ? //在接口中可以直接映射分頁對(duì)象
? ? List<</span>SaleBill> list(RowBounds rb);
? ? void delete(Long id);
? ? void deleteItems(Long billId);
}

@Test
public void testSave() {
? ? //創(chuàng)建SaleBill對(duì)象
? ? SaleBill sb = new SaleBill();
? ? sb.setSn("001");
? ? //創(chuàng)建一個(gè)明細(xì)對(duì)象
? ? SaleBillItem sbi = new SaleBillItem();
? ? sbi.setPrice(100d);
? ? sbi.setBill(sb);
? ? //創(chuàng)建一個(gè)明細(xì)對(duì)象
? ? SaleBillItem sbi2 = new SaleBillItem();
? ? sbi2.setPrice(300d);
? ? sbi2.setBill(sb);
? ? //處理關(guān)系
? ? sb.getItems().add(sbi);
? ? sb.getItems().add(sbi2);
? ? //保存
? ? SqlSession session = MyBatisUtil.openSession();
? ? SaleBillMapper mapper = session.getMapper(SaleBillMapper.class);
? ? //注意，先保存SaleBill對(duì)象
? ? mapper.saveSaleBill(sb);
? ? //保存明細(xì)對(duì)象
? ? mapper.saveSaleBillItem(sbi);
? ? mapper.saveSaleBillItem(sbi2);
? ? session.commit();
? ? session.close();
}
?
@Test
public void testGet() {
? ? SqlSession session = MyBatisUtil.openSession();
? ? //得到SaleBill對(duì)象
? ? SaleBillMapper mapper = session.getMapper(SaleBillMapper.class);
? ? SaleBill sb = mapper.get(5l);
? ? Set<</span>SaleBillItem> items = sb.getItems();
? ? for (SaleBillItem item : items) {
? ? ? ? ? ? System.out.println(item.getPrice());
? ? }
? ? session.close();
}
?
@Test
public void testDelete() {
? ? SqlSession session = MyBatisUtil.openSession();
? ? SaleBillMapper mapper = session.getMapper(SaleBillMapper.class);
? ? mapper.deleteItems(1l);
? ? mapper.delete(1l);
? ? session.commit();
? ? session.close();
} ? ?

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.cnpiec.ireader.dao.GetBookDataDao">
? ? <insert id="batchInsertBook" parameterType="Book">
? ? ? ? INSERT INTO BOOK (BOOKID,NAME,PARTNERNAME) VALUES
? ? ? ? <foreach collection="list" item="book" separator=",">
? ? ? ? ? ? (#{book.bookId}, #{book.name}, #{book.partnerName})
? ? ? ? </foreach>
? ? </insert>
</mapper>

<mappers>
? ? <mapper resource=” tk/mybatis/simple/mapper/CountryMapper.xml ” / >
? ? <mapper resource=” tk/mybatis/simple/mapper/UserMapper . xml ” / >
? ? <mapper resource=” tk/mybatis/simple/mapper/RoleMapper.xml ” />
? ? <mapper resource=” tk/mybatis/simple/mapper/PrivilegeMapper . xml ” />
? ? <mapper resource=” tk/mybatis/simple/mapper/UserRoleMapper . xml ” />
? ? <mapper resource=” tk/mybatis/simple/mapper / RolePrivilegeMapper.xml ” />
</mappers>

<mappers>
? ? <package name= ” tk.mybatis . simple . mapper ” />
</mappers>