1.用Maven創建我們的項目seckill

利用Maven去創建工程然后導入Idea中并完成相關配置，這里的注意點：

1. 1利用Maven創建web項目命令：mvn archetype:generate -DgroupId=org.seckill -DartifactId=seckill -DarchetypeArtifactId=maven-archetype-webapp -DarchetypeCatalog=local
   然后使用IDEA打開該項目，在IDEA中對項目按照Maven項目的標準骨架補全我們項目的相應文件包，最后的工程結構如下:

工程目錄

main包下進行我們項目的代碼編寫及相關配置文件，test包下進行我們junit單元測試。

打開WEB-INF下的web.xml，它默認為我們創建servlet版本為2.3

<web-app xmlns="http://java.sun.com/xml/ns/javaee"         
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"                          
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee                      
         http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"         
         version="3.0"         
         metadata-complete="true">  <!--用maven創建的web-app需要修改servlet的版本為3.0-->
</web-app>

然后打開pom.xml，在里面添加我們需要的第三方jar包的坐標配置信息，如SSM框架、數據庫、日志，如下:

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>org.seckill</groupId>
  <artifactId>seckill</artifactId>
  <packaging>war</packaging>
  <version>1.0-SNAPSHOT</version>
  <name>seckill Maven Webapp</name>
  <url>http://maven.apache.org</url>
  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
    <!-- slf4j是規范，接口 -->
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>1.7.12</version>
    </dependency>
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-core</artifactId>
        <version>1.1.1</version>
    </dependency>
    <!-- 實現slf4j接口并整合 -->
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>1.1.1</version>
    </dependency>
    <!-- 數據庫相關的依賴 -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.3</version>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>c3p0</groupId>
        <artifactId>c3p0</artifactId>
        <version>0.9.1.2</version>
    </dependency>
    <!-- dao框架，mybatis依賴 -->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.3.0</version>
    </dependency>
    <!-- mybatis整合spring的依賴 -->
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>1.2.3</version>
    </dependency>
    <!-- servlet-web相關的依賴 -->
    <dependency>
        <groupId>taglibs</groupId>
        <artifactId>standard</artifactId>
        <version>1.1.2</version>
    </dependency>
    <dependency>
        <groupId>jstl</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.5.4</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
    </dependency>
    <!-- spring依賴 -->
    <!-- 1、spring核心依賴 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-beans</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <!-- 2、spring dao依賴 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-tx</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <!-- 3、spring web依賴 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <!-- 3、spring test依賴 -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>4.1.7.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.apache.openejb</groupId>
        <artifactId>javaee-api</artifactId>
        <version>5.0-1</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>javax.faces</groupId>
        <artifactId>jsf-api</artifactId>
        <version>1.2_04</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet.jsp</groupId>
        <artifactId>jsp-api</artifactId>
        <version>2.1</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>javax.faces</groupId>
        <artifactId>jsf-impl</artifactId>
        <version>1.2_04</version>
        <scope>provided</scope>
    </dependency>
  </dependencies>
  <build>
    <finalName>seckill</finalName>
  </build>
</project>

到此，我們項目的初始化工作完成。

2. 秒殺系統業務分析

秒殺系統業務流程如下:

Paste_Image.png

由圖可以發現，整個系統其實是針對庫存做的系統。用戶成功秒殺商品，對于系統的操作就是:1.減庫存。2.記錄用戶的購買明細。
下面看看我們用戶對庫存的業務分析:

Paste_Image.png

記錄用戶的秒殺成功信息，需要記錄:1.誰購買成功了。2.購買成功的時間/有效期。3.付款/發貨信息。這些數據組成了用戶的秒殺成功信息，也就是用戶的購買行為。

為什么系統需要事務?看如下這些故障:1.若是用戶成功秒殺商品我們記錄了其購買明細卻沒有減庫存。導致商品的超賣。2.減了庫存卻沒有記錄用戶的購買明細。導致商品的少賣。對于上述兩個故障，若是沒有事務的支持，損失最大的無疑是我們的用戶和商家。在MySQL中，它內置的事務機制，可以準確的幫我們完成減庫存和記錄用戶購買明細的過程。

MySQL實現秒殺的難點分析:當用戶A秒殺id為10的商品時，此時MySQL需要進行的操作是:1.開啟事務。2.更新商品的庫存信息。3.添加用戶的購買明細，包括用戶秒殺的商品id以及唯一標識用戶身份的信息如電話號碼等。4.提交事務。若此時有另一個用戶B也在秒殺這件id為10的商品，他就需要等待，等待到用戶A成功秒殺到這件商品然后MySQL成功的提交了事務他才能拿到這個id為10的商品的鎖從而進行秒殺，而同一時間是不可能只有用戶B在等待，肯定是有很多很多的用戶都在等待拿到這個行級鎖。秒殺的難點就在這里，如何高效的處理這些競爭？如何高效的完成事務?在后面模塊如何進行高并發的優化。

3. Dao層設計開發

首先創建數據庫數據表，通過手寫sql。

-- 創建數據庫
create database seckill;

-- 使用數據庫
use seckill;

-- 創建數據表
create table seckill(
  seckill_id bigint not null auto_increment comment '商品庫存id',
  name varchar(120) not null comment '商品名稱',
  number int(11) not null comment '庫存數量',
  create_time timestamp not null default current_timestamp comment '創建時間',
  start_time timestamp not null comment '秒殺開始時間',
  end_time timestamp not null comment '秒殺介紹時間',
  primary key (seckill_id),
  key idx_start_time (start_time),
  key idx_end_time (end_time),
  key idx_create_time (create_time)
) engine innodb auto_increment = 1000 default charset = utf8 comment '秒殺庫存表';

--  初始化數據
insert into
  seckill(name,number,start_time,end_time)
value
  ('2000元秒殺iphone7',  200,'2017-01-05 00:00:00','2017-01-06 00:00:00'),
  ('500元秒殺華為P9',    300,'2017-01-05 00:00:00','2017-01-06 00:00:00'),
  ('2000元秒殺華為MATE9',400,'2017-01-05 00:00:00','2017-01-06 00:00:00'),
  ('2500元秒殺小米MIX',  100,'2017-01-05 00:00:00','2017-01-06 00:00:00');

-- 秒殺成功明細表
create table seccess_killed(
  seckill_id bigint(20) not null comment '秒殺商品id',
  user_phone bigint(20) not null comment '用戶手機',
  state tinyint not null default -1 comment '狀態標示：-1：無效 0：成功 1：已付款 2：已發貨',
  create_time timestamp not null default current_timestamp comment '創建時間',
  primary key (seckill_id,user_phone),
  key idx_create_time (create_time)
) engine=innodb charset=utf8 comment='秒殺成功明細表';

然后創建對應表的實體類。
Seckill.java，代碼如下:

package org.seckill.entity;

import java.util.Date;
/**
 * Created by joshul on 2016/12/30.
 */
public class Seckill {

    private long seckillId;
    private String name;
    private int number;
    private Date startTime;
    private Date endTime;
    private Date createTime;

    public long getSeckillId() {
        return seckillId;
    }

    public void setSeckillId(long seckillId) {
        this.seckillId = seckillId;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getNumber() {
        return number;
    }

    public void setNumber(int number) {
        this.number = number;
    }

    public Date getStartTime() {
        return startTime;
    }

    public void setStartTime(Date startTime) {
        this.startTime = startTime;
    }

    public Date getEndTime() {
        return endTime;
    }

    public void setEndTime(Date endTime) {
        this.endTime = endTime;
    }

    public Date getCreateTime() {
        return createTime;
    }

    public void setCreateTime(Date createTime) {
        this.createTime = createTime;
    }

    @Override
    public String toString() {
        return "Seckill{" +
                "seckillId=" + seckillId +
                ", name='" + name + '\'' +
                ", number=" + number +
                ", startTime=" + startTime +
                ", endTime=" + endTime +
                ", createTime=" + createTime +
                '}';
    }
}

SuccessKilled.java，代碼如下:

package org.seckill.entity;

import java.util.Date;

public class SuccessKilled {
    private long seckilled;//成功秒殺過的id
    private long userPhone;//用戶電話
    private short state; //用來記錄交易狀態
    private Date createTime;//記錄創建時間

    private Seckill seckill;//變通，多對一

    public long getSeckilled() {
        return seckilled;
    }

    public void setSeckilled(long seckilled) {
        this.seckilled = seckilled;
    }

    public long getUserPhone() {
        return userPhone;
    }

    public void setUserPhone(long userPhone) {
        this.userPhone = userPhone;
    }

    public short getState() {
        return state;
    }

    public void setState(short state) {
        this.state = state;
    }

    public Date getCreateTime() {
        return createTime;
    }

    public void setCreateTime(Date createTime) {
        this.createTime = createTime;
    }

    public Seckill getSeckill() {
        return seckill;
    }

    public void setSeckill(Seckill seckill) {
        this.seckill = seckill;
    }

    @Override
    public String toString() {
        return "SuccessKilled{" +
                "seckilled=" + seckilled +
                ", userPhone=" + userPhone +
                ", state=" + state +
                ", createTime=" + createTime +
                '}';
    }
}   

針對實體創建出對應dao層的接口，在com.joshul.seckill.dao包下
Seckill.java:

package org.seckill.dao;

import java.util.Date;
import java.util.List;

import org.apache.ibatis.annotations.Param;

import org.seckill.entity.Seckill;

public interface SeckillDao {
    /**
     * 減庫存
     * @param seckillId
     * @param killTime
     * @return 如果影響的行數大于1，表示更新記錄行數
     */
    int reduceNumber(@Param("seckillId")long seckillId, @Param("killTime")Date killTime);

    /**
     * 根據id查詢秒殺對象
     * @param seckillId
     * @return
     */
    Seckill queryById(@Param("seckillId")long seckillId);
    /**
     * 根據偏移量查詢秒殺商品列表
     * @param offet
     * @param limit
     * @return
     */
    List<Seckill> queryAll(@Param("offset") int offet,@Param("limit")int limit);
}

SuccessKilled.java:

package org.seckill.dao;

import org.apache.ibatis.annotations.Param;

import org.seckill.entity.SuccessKilled;


public interface SuccessSeckilledDao {
    /**
     * 插入購買明細，可過濾重復
     * @param seckillId
     * @param userPhone
     * @return 插入的行數
     */
    int insertSuccessSeckilled(@Param("seckillId") long seckillId,@Param("userPhone") long userPhone);
    /**
     * 根據id查詢SuccessKilled并攜帶秒殺產品對象實例
     * @param seckillId
     * @return
     */
    SuccessKilled queryByIdWithSeckill(@Param("seckillId") long seckillId,@Param("userPhone") long userPhone);
}

接下來基于MyBatis來實現之前設計的Dao層接口。
在mybatis-config.xml加入如下配置信息:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
    PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
    "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>
    <settings>
        <!--使用jdbc的getGeneratedKeys 獲取數據庫自增主鍵值-->
        <setting name="useGeneratedKeys" value="true"/>
        <!--使用列別名替換列名 默認：true select name as title from table-->
        <setting name="useColumnLabel" value="true"/>
        <!--開起駝峰命名轉換：Table(create_time) ->Entity(createTime) –>-->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>

配置文件創建好后需要關注的是Dao接口該如何實現，mybatis為提供了mapper動態代理開發的方式為自動實現Dao的接口。在mapper包下創建對應Dao接口的xml映射文件，里面用于編寫操作數據庫的sql語句，SeckillDao.xml和SuccessKilledDao.xml。

SeckillDao.xml:

<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="org.seckill.dao.SeckillDao">
    <!--目的：為DAO借口方法提供sql配置-->
    <update id="reduceNumber">
         update
           seckill
         set
           number=number -1
         where seckill_id = #{seckillId}
         and start_time <![CDATA[ <= ]]>   #{killTime}
         and end_time >= #{killTime}
         and number > 0;
    </update>
    <select id="queryById" resultType="Seckill" parameterType="long">
         select seckill_id,name,number,start_time, end_time, create_time
         from seckill
         where seckill_id=#{seckillId}
    </select>

    <select id="queryAll" resultType="Seckill">
         select seckill_id,name,number,start_time,end_time,create_time
         from seckill
         order by create_time DESC
         limit #{offset},#{limit}
    </select>
</mapper>

SuccessKilledDao.xml:

<?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">
<!-- 命名空間，用于對SQL的分類管理 -->
<mapper namespace="org.seckill.dao.SuccessSeckilledDao">
    <insert id="insertSuccessSeckilled">
        insert ignore into success_skilled(seckill_id,user_phone,state)
        values(#{seckillId},#{userPhone},0)
    </insert>
    <!--根據id查詢SuccessKilled并攜帶Seckill實體-->
    <!--如何告訴Mybatis把結果映射到SuccessKilled同時映射seckill屬性-->
    <!--可以自由控制SQL-->
    <select id="queryByIdWithSeckill" resultType="Successkilled">
        select
            sk.seckill_id,
            sk.user_phone,
            sk.create_time,
            sk.state,
            <!--通過別名的方式來將查詢結果封裝到Successkilled的seckill屬性中-->
            s.seckill_id "seckill.seckill_id",
            s.name "seckill.name",
            s.number "seckill.number",
            s.start_time "seckill.start_time",
            s.end_time "seckill.end_time",
            s.create_time "seckill.create_time"
        from success_skilled sk
        inner join seckill s on sk.seckill_id=s.seckill_id
        where sk.seckill_id=#{seckillId} and sk.user_phone=#{userPhone}
    </select>
</mapper>

接下來開始MyBatis和Spring的整合，整合目標:
1.更少的編碼:只寫接口，不寫實現類。
2.更少的配置:別名、配置掃描映射xml文件、dao實現。
3.足夠的靈活性:自由定制SQL語句、自由傳結果集自動賦值。

在resources包下創建一個spring包，里面放置spring對Dao、Service、transaction的配置文件。
在spring包下創建一個spring配置dao層對象的配置文件spring-dao.xml內容如下:

<?xml version="1.0" encoding="UTF-8"?>
<beans
    xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:p="http://www.springframework.org/schema/p" 
    xmlns:aop="http://www.springframework.org/schema/aop"
    xsi:schemaLocation="http://www.springframework.org/schema/beans 
                        http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
                        http://www.springframework.org/schema/tx
                        http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
                        http://www.springframework.org/schema/mvc
                        http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
                        http://www.springframework.org/schema/context 
                        http://www.springframework.org/schema/context/spring-context-2.5.xsd
                        http://www.springframework.org/schema/aop
                        http://www.springframework.org/schema/aop/spring-aop-4.3.xsd 
                        http://www.springframework.org/schema/p
                        http://www.springframework.org/schema/p/spring-aop-4.3.xsd 
                        http://www.springframework.org/schema/c
                        http://www.springframework.org/schema/c/spring-aop-4.3.xsd ">
<!-- 引入db.properties-->
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="location" value="classpath:db.properties"></property>
</bean>
<!-- 配置c3p0 -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
    <!-- 數據庫的基本配置 -->
    <property name="driverClass" value="${db.driver}"></property>
    <property name="jdbcUrl" value="${db.url}"></property>
    <property name="user" value="${db.username}"></property>
    <property name="password" value="${db.password}"></property>
    <!-- 配置c3p0的屬性 -->
    <property name="maxPoolSize" value="30"></property>
    <property name="minPoolSize" value="10"></property>
    <!--關閉連接后不自動commit-->
    <property name="autoCommitOnClose" value="false"/>
    <!--獲取連接超時時間-->
    <property name="checkoutTimeout" value="1000"></property>
    <!--當獲取連接失敗重試次數-->
    <property name="acquireRetryAttempts" value="2"/>
</bean>
<!-- 配置 SqlSessionFactoryBean-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    <!--注入數據庫連接池-->
    <property name="dataSource" ref="dataSource"></property>
    <!--配置mybatis全局配置文件：mybatis-config.xml-->
    <property name="configLocation" value="classpath:mybatis-config.xml"></property>
    <!--掃描entity包 使用別名-->
    <property name="typeAliasesPackage" value="org.seckill.entity"></property>
    <!--掃描sql配置文件：mapper需要的xml文件-->
    <property name="mapperLocations" value="classpath:mapper/*.xml"></property>
</bean>
<!-- 配置掃描dao接口包，動態實現dao接口，注入spring容器中 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
    <!--當sqlSessionFactory bean啟動的時候，properties還未加載，所以通過BeanName后處理的方式-->
    <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property>
    <!--給出需要掃描Dao接口包-->
    <property name="basePackage" value="org.seckill.dao"></property>
</bean>
</beans>

這樣便完成了Dao層編碼的開發，接下來就可以利用junit進行Dao層編碼的測試了。首先測試SeckillDao.java，利用IDEA快捷鍵shift+command+T
對SeckillDao.java進行測試，然后IDEA會自動在test包的java包下為生成對SeckillDao.java中所有方法的測試類SeckillDaoTest.java,內容如下:

package org.seckill.dao;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.seckill.entity.Seckill;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import javax.annotation.Resource;

import java.util.Date;
import java.util.List;

import static org.junit.Assert.*;

/**
 * Created by joshul on 2017/1/3.
 */

//junit啟動時加載springIOC容器
@RunWith(SpringJUnit4ClassRunner.class)
//告訴junit spring配置文件
@ContextConfiguration({"classpath:spring/spring-dao.xml"})
public class SeckillDaoTest {
    //注入Dao實現類依賴
    @Resource
    private SeckillDao seckillDao;

    @Test
    public void queryById() throws Exception {
        long id = 1000L;
        Seckill seckill = seckillDao.queryById(id);
        System.out.println(seckill.getNumber());
        System.out.println(seckill);
    }

    @Test
    public void queryAll() throws Exception {
        /**
         * java不會保存形參的記錄，queryAll(int offset,int limit)會被解釋成queryAll(int arg0,int arg1）
         * 所以會出現綁定錯誤，需要在接口的形參中使用@Param注解
         */
        List<Seckill> seckills = seckillDao.queryAll(0,100);
        for (Seckill seckill:seckills) {
            System.out.println(seckill);
        }
    }

    @Test
    public void reduceNumber() throws Exception {
        Date killTime = new Date();
        int updateCount = seckillDao.reduceNumber(1000L,killTime);
        System.out.println(updateCount);
    }
}

SuccessSeckilledDaoTest

package org.seckill.dao;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.seckill.entity.SuccessKilled;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

import javax.annotation.Resource;

import static org.junit.Assert.*;

/**
 *
 */
//junit啟動時加載springIOC容器
@RunWith(SpringJUnit4ClassRunner.class)
//告訴junit spring配置文件
@ContextConfiguration({"classpath:spring/spring-dao.xml"})
public class SuccessSeckilledDaoTest {

    @Resource
    private SuccessSeckilledDao successSeckilledDao;

    @Test
    public void insertSuccessKilled() throws Exception {
        Long id = 1001L;
        long phone = 13877511732L;
        int insertCount = successSeckilledDao.insertSuccessSeckilled(id,phone);
        System.out.println("insertCount = " + insertCount);
    }

    @Test
    public void queryByIdwithSeckill() throws Exception {
        Long id = 1001L;
        long phone = 13877511732L;
        SuccessKilled successKilled = successSeckilledDao.queryByIdWithSeckill(id,phone);
        System.out.println(successKilled);
        System.out.println(successKilled.getSeckill());
    }

}

到此，成功完成了Dao層開發及測試，接下來我們將進行Service層的開發工作。
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