1、需求分析和技术难点：
(1) 分析：
秒杀的时候：减少库存和购买记录明细两个事件保持在同一个事物中。
使用联合查询避免同一用户多次秒杀同一商品（利用在插入购物明细表中的秒杀id和用户的唯一标识来避免）。
(2) 秒杀难点:事务和行级锁的处理
(3) 实现那些秒杀系统(以天猫的秒杀系统为例)
(4) 我们如何实现秒杀功能?
① 秒杀接口暴漏
② 执行秒杀
③ 相关查询
下面我们以主要代码实现秒杀系统：
PS：由于文章字符限制，没有办法将所有的代码列在文章中，大家可以在公众号内回复
”秒杀“
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2.数据库设计和DAO层
(1) 数据库设计
(2) Dao层和对应的实体
① Seckill.java
② SuccessKilled.java
③ SeckillDao
④ SuccessKilledDao
⑤ mybatis配置文件：
⑥ SeckillDao.xml
⑦ SuccessKilledDao.xml
⑧ Mybatis整合Service：spring-dao.xml
3 Service层
① SeckillService
② SeckillServiceImpl
③ 异常的处理：
a.SeckillCloseException
b. SeckillException
c. RepeatKillException
④ 枚举SeckillStatEnum
⑤ spring_spring.xml文件
4.Web层,JSP页面和JS
(1) 详情页流程逻辑逻辑
(2) 配置web.xml
(3) SeckillResult
(4) spring-web.xml
(5) SeckillController中：
package com.force4us.web;
import com.force4us.dto.Exposer;
import com.force4us.dto.SeckillExecution;
import com.force4us.dto.SeckillResult;
import com.force4us.entity.Seckill;
import com.force4us.enums.SeckillStatEnum;
import com.force4us.exception.RepeatKillException;
import com.force4us.exception.SeckillCloseException;
import com.force4us.exception.SeckillException;
import com.force4us.service.SeckillService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.test.annotation.Repeat;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.*;
import java.util.Date;
import java.util.List;
@Controller
@RequestMapping("/seckill")
public class SeckillController {
@Autowired
private SeckillService seckillService;
@RequestMapping(value = "/list",method= RequestMethod.GET)
public String list(Model model) {
List<Seckill> list = seckillService.getSeckillList();
model.addAttribute("list",list);
return "list";
}
@RequestMapping(value = "/{seckillId}/detail",method = RequestMethod.GET)
public String detail(@PathVariable("seckillId") Long seckillId, Model model){
if(seckillId == null){
return "redirect:/seckill/list";
}
Seckill seckill = seckillService.getById(seckillId);
if(seckill == null){
return "forward:/seckill/list";
}
model.addAttribute("seckill", seckill);
return "detail";
}
//ajax ,json暴露秒杀接口的方法
@RequestMapping(value="/{seckillId}/exposer",method = RequestMethod.POST,produces = {"application/json;charset=UTF-8"})
@ResponseBody
public SeckillResult<Exposer> exposer(@PathVariable("seckillId") Long seckillId){
SeckillResult<Exposer> result;
try {
Exposer exposer = seckillService.exportSeckillUrl(seckillId);
result = new SeckillResult<Exposer>(true,exposer);
} catch (Exception e) {
e.printStackTrace();
result = new SeckillResult<Exposer>(false,e.getMessage());
}
return result;
}
@RequestMapping(value="/{seckillId}/{md5}/execution", method = RequestMethod.POST,
produces = {"application/json;charset=UTF-8"})
@ResponseBody
public SeckillResult<SeckillExecution> execute(@PathVariable("seckillId") Long seckillId,
@PathVariable("md5") String md5,
@CookieValue(value="killPhone", required = false) Long phone){
if(phone == null){
return new SeckillResult<SeckillExecution>(false,"未注册");
}
SeckillResult<SeckillExecution> result;
try {
SeckillExecution execution = seckillService.executeSeckillProcedure(seckillId,phone, md5);
return new SeckillResult<SeckillExecution>(true,execution);
} catch (RepeatKillException e1) {
SeckillExecution execution = new SeckillExecution(seckillId, SeckillStatEnum.REPEAT_KILL);
return new SeckillResult<SeckillExecution>(true,execution);
} catch(SeckillCloseException e2){
SeckillExecution execution = new SeckillExecution(seckillId, SeckillStatEnum.END);
return new SeckillResult<SeckillExecution>(true,execution);
}catch(Exception e){
SeckillExecution execution = new SeckillExecution(seckillId, SeckillStatEnum.INNER_ERROR);
return new SeckillResult<SeckillExecution>(true,execution);
}
}
@RequestMapping(value = "/time/now", method = RequestMethod.GET)
@ResponseBody
public SeckillResult<Long> time(){
Date now = new Date();
return new SeckillResult<Long>(true,now.getTime());
}
@RequestMapping("/test")
public String test(){
return "helloworld";
}
}
(6) list.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@include file="common/tag.jsp"%>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
<title>秒杀列表页</title>
<%@include file="/WEB-INF/jsp/common/head.jsp"%>
</head>
<body>
<div class="container">
<div class="panel panel-default">
<div class="panel-heading text-center">
<h2>秒杀列表</h2>
</div>
<div class="panel-body">
<table class="table table-hover">
<thead>
<tr>
<th>名称</th>
<th>库存</th>
<th>开始时间</th>
<th>结束时间</th>
<th>创建时间</th>
<th>详情页</th>
</tr>
</thead>
<tbody>
<c:forEach items="${list}" var="sk">
<tr>
<td>${sk.name}</td>
<td>${sk.number}</td>
<td>
<fmt:formatDate value="${sk.startTime}" pattern="yyyy-MM-dd HH:mm:ss" />
</td>
<td>
<fmt:formatDate value="${sk.endTime}" pattern="yyyy-MM-dd HH:mm:ss" />
</td>
<td>
<fmt:formatDate value="${sk.createTime}" pattern="yyyy-MM-dd HH:mm:ss" />
</td>
<td><a class="btn btn-info" href="/seckill/${sk.seckillId}/detail" target="_blank">详情</a></td>
</tr>
</c:forEach>
</tbody>
</table>
</div>
</div>
</div>
</body>
<!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->
<script src="https://cdn.bootcss.com/jquery/1.12.4/jquery.min.js"></script>
<!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
<script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
</html>
(7) details.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@include file="common/tag.jsp"%>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
<title>秒杀详情页</title>
<%@include file="common/head.jsp"%>
</head>
<body>
<div class="container">
<div class="panel panel-default text-center">
<div class="pannel-heading">
<h1>${seckill.name}</h1>
</div>
<div class="panel-body">
<h2 class="text-danger">
<%--显示time图标--%>
<span class="glyphicon glyphicon-time"></span>
<%--展示倒计时--%>
<span class="glyphicon" id="seckill-box"></span>
</h2>
</div>
</div>
</div>
<%--登录弹出层 输入电话--%>
<div id="killPhoneModal" class="modal fade">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<h3 class="modal-title text-center">
<span class="glyphicon glyphicon-phone"> </span>秒杀电话:
</h3>
</div>
<div class="modal-body">
<div class="row">
<div class="col-xs-8 col-xs-offset-2">
<input type="text" name="killPhone" id="killPhoneKey"
placeholder="填写手机号^o^" class="form-control">
</div>
</div>
</div>
<div class="modal-footer">
<%--验证信息--%>
<span id="killPhoneMessage" class="glyphicon"> </span>
<button type="button" id="killPhoneBtn" class="btn btn-success">
<span class="glyphicon glyphicon-phone"></span>
Submit
</button>
</div>
</div>
</div>
</div>
</body>
<!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->
<script src="https://cdn.bootcss.com/jquery/1.12.4/jquery.min.js"></script>
<!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
<script src="https://cdn.bootcss.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>
<%--jQuery Cookie操作插件--%>
<script src="https://cdn.bootcss.com/jquery-cookie/1.4.1/jquery.cookie.min.js"></script>
<%--jQuery countDown倒计时插件--%>
<script src="https://cdn.bootcss.com/jquery.countdown/2.2.0/jquery.countdown.min.js"></script>
<script src="/resource/script/seckill.js" typ="text/javascript"></script>
<script type="text/javascript">
$(function(){
seckill.detail.init({
seckillId:${seckill.seckillId},
startTime:${seckill.startTime.time},
endTime:${seckill.endTime.time}
});
})
</script>
</html>
(8) seckill.js
//存放主要交互逻辑的js代码
// javascript 模块化(package.类.方法)
var seckill = {
//封装秒杀相关ajax的url
URL: {
now: function () {
return '/seckill/time/now';
},
exposer: function (seckillId) {
return '/seckill/' + seckillId + '/exposer';
},
execution: function (seckillId, md5) {
return '/seckill/' + seckillId + '/' + md5 + '/execution';
}
},
//验证手机号
validatePhone: function(phone){
if(phone && phone.length == 11 && !isNaN(phone)){
return true;
}else{
return false;
}
},
//详情页秒杀逻辑
detail:{
//详情页初始化
init:function (params) {
//手机验证和登录，计时交互
//规划我们的交互流程
//在cookie中查找手机号
var killPhone = $.cookie('killPhone');
//验证手机号
if(!seckill.validatePhone(killPhone)){
//绑定手机，控制输出
var killPhoneModal = $('#killPhoneModal');
killPhoneModal.modal({
show:true,//显示弹出层
backdrop:'static',//禁止位置关闭
keyboard:false//关闭键盘事件
});
$('#killPhoneBtn').click(function () {
var inputPhone = $('#killPhoneKey').val();
console.log("inputPhone" + inputPhone);
if(seckill.validatePhone(inputPhone)){
//电话写入cookie，7天过期
$.cookie('killPhone',inputPhone,{expires:7, path:'/seckill'});
//验证通过，刷新页面
window.location.reload();
}else{
$('#killPhoneMessage').hide().html('<label class="label label-danger">手机号错误</label>').show(300);
}
});
}
//已经登录
//计时交互
var startTime = params['startTime'];
var endTime = params['endTime'];
var seckillId = params['seckillId'];
$.get(seckill.URL.now(), {}, function (result) {
if (result && result['success']) {
var nowTime = result['data'];
//时间判断 计时交互
seckill.countDown(seckillId, nowTime, startTime, endTime);
} else {
console.log('result: ' + result);
alert('result: ' + result);
}
});
}
},
handlerSeckill: function (seckillId, node) {
//获取秒杀地址,控制显示器,执行秒杀
node.hide().html('<button class="btn btn-primary btn-lg" id="killBtn">开始秒杀</button>');
$.post(seckill.URL.exposer(seckillId), {}, function (result) {
//在回调函数种执行交互流程
if (result && result['success']) {
var exposer = result['data'];
if (exposer['exposed']) {
//开启秒杀
//获取秒杀地址
var md5 = exposer['md5'];
var killUrl = seckill.URL.execution(seckillId, md5);
console.log("killUrl: " + killUrl);
//绑定一次点击事件
$('#killBtn').one('click', function () {
//执行秒杀请求
//1.先禁用按钮
$(this).addClass('disabled');//,<-$(this)===('#killBtn')->
//2.发送秒杀请求执行秒杀
$.post(killUrl, {}, function (result) {
if (result && result['success']) {
var killResult = result['data'];
var state = killResult['state'];
var stateInfo = killResult['stateInfo'];
//显示秒杀结果
node.html('<span class="label label-success">' + stateInfo + '</span>');
}
});
});
node.show();
} else {
//未开启秒杀(浏览器计时偏差)
var now = exposer['now'];
var start = exposer['start'];
var end = exposer['end'];
seckill.countDown(seckillId, now, start, end);
}
} else {
console.log('result: ' + result);
}
});
},
countDown: function (seckillId, nowTime, startTime, endTime) {
console.log(seckillId + '_' + nowTime + '_' + startTime + '_' + endTime);
var seckillBox = $('#seckill-box');
if (nowTime > endTime) {
//秒杀结束
seckillBox.html('秒杀结束!');
} else if (nowTime < startTime) {
//秒杀未开始,计时事件绑定
var killTime = new Date(startTime + 1000);//todo 防止时间偏移
seckillBox.countdown(killTime, function (event) {
//时间格式
var format = event.strftime('秒杀倒计时: %D天 %H时 %M分 %S秒 ');
seckillBox.html(format);
}).on('finish.countdown', function () {
//时间完成后回调事件
//获取秒杀地址,控制现实逻辑,执行秒杀
console.log('______fininsh.countdown');
seckill.handlerSeckill(seckillId, seckillBox);
});
} else {
//秒杀开始
seckill.handlerSeckill(seckillId, seckillBox);
}
}
}
5.优化：
由于减少库存和购买明细需要在同一事物当中，在次中间会出现网络延迟，GC，缓存，数据库的并发等，所以需要进行优化。
(1) 使用Redis优化：具体代码看上面。
(2) 调整业务逻辑：先进行insert，插入购买明细，然后进行减少库存数量，具体代码看上面。
(3) 调用存储过程seckill.sql
6.系统部署：
到这里，已经基本完工。由于文章字符限制，没有办法将所有的代码列在文章中，大家可以在公众号内回复
”秒杀“
获取源码，方便您的学习
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