基于Redis结合SpringBoot的秒杀案例详解

<?xml version="1.0" encoding="UTF-8"?>
<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.13.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.baizhi</groupId>
    <artifactId>quickbuy</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>quickbuy</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.5.5</version>
        </dependency>

        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpcore</artifactId>
            <version>4.4.10</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

package com.baizhi;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class QuickbuyApplication {

    public static void main(String[] args) {
        SpringApplication.run(QuickbuyApplication.class, args);
    }
}

@RestController
public class QuickBuyController {
    @Autowired
    private SellService sellService;

    @RequestMapping("/quickBuy/{item}/{owner}")
    public String quickbuy(@PathVariable String item,@PathVariable String owner){
        String result=sellService.quickBuy(item,owner);
        if(!result.equals("0")){
            return owner+"success";
        }else{
            return owner+"fail";
        }
    }
}

package com.baizhi.service;

import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.connection.ReturnType;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

@Service
public class SellService {
    @Resource
    private RedisTemplate redisTemplate;

    public String quickBuy(String item, String owner) {
        //用lua脚本实现秒杀
        String luaScript="local owner=ARGV[1]\n" +
                "local item=KEYS[1] \n" +
                "local leftNum=tonumber(redis.call('get',item)) \n" +
                "if(leftNum>=1)\n" +
                "then redis.call('decrby',item,1)\n" +
                "redis.call('rpush','ownerList',owner)\n" +
                "return 1 \n" +
                "else \n" +
                "return 0 \n" +
                "end\n" +
                "\n";
        String key=item;
        String args=owner;
        DefaultRedisScript<String> redisScript=new DefaultRedisScript<String>();
        redisScript.setScriptText(luaScript);
        //调用lua脚本，请注意传入的参数
        Object luaResult=redisTemplate.execute((RedisConnection connection)->connection.eval(
           redisScript.getScriptAsString().getBytes(),
           ReturnType.INTEGER,
           1,
           key.getBytes(),
           args.getBytes()
        ));
        //根据lua脚本的执行情况返回结果
        return luaResult.toString();
    }
}

server.port=8081

spring.redis.host=192.168.159.22
spring.redis.port=6379

package com.baizhi.client;

import org.apache.http.HttpEntity;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.apache.http.util.EntityUtils;

public class QuickBuyClients extends Thread{
    @Override
    public void run() {
        QuickBuyUtil.quickBuy();
    }

    public static void main(String[] args) {
        //开启15个线程，线程数多余秒杀商品数
        for(int cnt=0;cnt<15;cnt++){
            new QuickBuyClients().start();
        }
    }
}
//封装秒杀方法的工具类
class QuickBuyUtil{
    //在这个方法里，用HttpGet对象发起秒杀请求
    public static void quickBuy(){
        String user=Thread.currentThread().getName();
        CloseableHttpClient httpClient= HttpClientBuilder.create().build();
        //创建秒杀Get类型的url请求
        HttpGet httpGet=new HttpGet("http://localhost:8081/quickBuy/Computer/"+user);
        //得到响应结果
        CloseableHttpResponse res=null;
        try{
            res=httpClient.execute(httpGet);
            HttpEntity responseEntity=res.getEntity();
            if(res.getStatusLine().equals("200")&&responseEntity!=null){
                System.out.println("秒杀结果："+ EntityUtils.toString(responseEntity));
            }
        }catch (ClientProtocolException e){
            e.printStackTrace();
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            try{
                //回收http连接资源
                if(httpClient!=null){
                    httpClient.close();
                }
                if(res!=null){
                    res.close();
                }
            }catch (Exception e){
                e.printStackTrace();
            }
        }
    }
}