Java电商秒杀实战1

搭建springboot项目

添加依赖

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

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


    <dependency>
      <groupId>org.springframework.boot</groupId>
      <artifactId>spring-boot-configuration-processor</artifactId>
      <optional>true</optional>
    </dependency>

    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
    </dependency>

    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.0.5</version>
    </dependency>

目录结构

 

集成Mybatis

添加mybatis-spring-boot-starter依赖

    <dependency>
      <groupId>org.mybatis.spring.boot</groupId>
      <artifactId>mybatis-spring-boot-starter</artifactId>
      <version>1.3.2</version>
    </dependency>

添加配置

#mybatis
mybatis.type-aliases-package=com.imooc.miaosha.domain
mybatis.configuration.map-underscore-to-camel-case=true
mybatis.configuration.default-fetch-size=100
mybatis.configuration.default-statement-timeout=3000
mybatis.mapperLocations=classpath:com/imooc/miaosha/dao/*.xml

添加druid配置

#druid
spring.datasource.url=jdbc:mysql://localhost:3306/miaosha?useUnicode=true&characterEncoding=UTF-8&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=123
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.filters=stat
spring.datasource.tomcat.max-active=2
spring.datasource.dbcp2.initial-size=1
spring.datasource.tomcat.max-wait=60000
spring.datasource.tomcat.min-idle=1
spring.datasource.tomcat.time-between-eviction-runs-millis=60000
spring.datasource.tomcat.min-evictable-idle-time-millis=300000
spring.datasource.tomcat.validation-query=select 'x'
spring.datasource.tomcat.test-on-borrow=true
spring.datasource.dbcp2.test-on-borrow=false
spring.datasource.dbcp2.test-on-return=false
spring.datasource.dbcp2.pool-prepared-statements=true
spring.datasource.dbcp2.max-open-prepared-statements=20

添加mysql、druid依赖

    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
    </dependency>

    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>druid</artifactId>
      <version>1.0.5</version>
    </dependency>

 

集成redis

首先安装Redis

修改配置文件redis.conf

将bind 127.0.0.1注释掉

修改daemonize为yes

设置密码

redies连接失败：Could not get a resource from the pool] with root cause

解决方法：关闭linux中的防火墙

命令：systemctl stop firewalld

添加Jedis依赖、添加Fastison依赖

    <dependency>
      <groupId>redis.clients</groupId>
      <artifactId>jedis</artifactId>
    </dependency>

    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>fastjson</artifactId>
      <version>1.2.38</version>
    </dependency>

添加redis配置

#redis
spring.redis.host=47.97.197.62
spring.redis.port=6379
spring.redis.timeout=3
spring.redis.password=123456
spring.redis.pool-max-total=10
spring.redis.pool.max-idle=10
spring.redis.pool.max-wait=3
spring.redis.pool.max-active=8

 RedisConfig

package com.imooc.miaosha.redis;

import org.apache.ibatis.annotations.Param;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.stereotype.Component;

@Component
@ConfigurationProperties(prefix ="spring.redis")
public class RedisConfig {
    private String host;
    private int port;
    private int timeout;
    private String password;
    private int poolMaxTotal;
    private int poolMaxIdle;
    private int poolMaxWait;

    public String getHost() {
        return host;
    }

    public void setHost(String host) {
        this.host = host;
    }

    public int getPort() {
        return port;
    }

    public void setPort(int port) {
        this.port = port;
    }

    public int getTimeout() {
        return timeout;
    }

    public void setTimeout(int timeout) {
        this.timeout = timeout;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public int getPoolMaxTotal() {
        return poolMaxTotal;
    }

    public void setPoolMaxTotal(int poolMaxTotal) {
        this.poolMaxTotal = poolMaxTotal;
    }

    public int getPoolMaxIdle() {
        return poolMaxIdle;
    }

    public void setPoolMaxIdle(int poolMaxIdle) {
        this.poolMaxIdle = poolMaxIdle;
    }

    public int getPoolMaxWait() {
        return poolMaxWait;
    }

    public void setPoolMaxWait(int poolMaxWait) {
        this.poolMaxWait = poolMaxWait;
    }
}

 RedisService

package com.imooc.miaosha.redis;

import com.alibaba.fastjson.JSON;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.stereotype.Service;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;
import redis.clients.jedis.JedisPoolConfig;

@Service
public class RedisService {

    @Autowired
    JedisPool jedisPool;

    /**
     * 获取单个对象
     */
    public <T> T get(KeyPrefix prefix,String key, Class<T> clazz) {
        Jedis jedis=null;
        try{
            jedis=jedisPool.getResource();
            //生成真正的key
            String realKey=prefix.getPrefix()+key;
            String str= jedis.get(realKey);
            T t=stringToBean(str,clazz);
            return t;
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 设置对象
     */
    public <T>boolean set(KeyPrefix prefix, String key, T value) {
        Jedis jedis=null;
        try{
            jedis=jedisPool.getResource();
            String str= beanToString(value);
            if(str==null||str.length()<=0){
                return false;

            }
            //生成真正的key
            String realKey=prefix.getPrefix()+key;
            int seconds= prefix.expireSeconds();
            if(seconds<=0){
                jedis.set(realKey,str);
            }else {
                jedis.setex(realKey,seconds,str);
            };
            return true;
        }finally {
            returnToPool(jedis);
        }
    }


    /**
     * 判断key是否存在
     */
    public <T>boolean exists(KeyPrefix prefix, String key) {
        Jedis jedis=null;
        try{
            jedis=jedisPool.getResource();
            //生成真正的key
            String realKey=prefix.getPrefix()+key;
            return jedis.exists(realKey);
        }finally {
            returnToPool(jedis);
        }
    }


    /**
     * 增加值
     */
    public <T>Long incr(KeyPrefix prefix, String key) {
        Jedis jedis=null;
        try{
            jedis=jedisPool.getResource();
            //生成真正的key
            String realKey=prefix.getPrefix()+key;
            return jedis.incr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 减少值
     */
    public <T> Long decr(KeyPrefix prefix, String key) {
        Jedis jedis=null;
        try{
            jedis=jedisPool.getResource();
            //生成真正的key
            String realKey=prefix.getPrefix()+key;
            return jedis.decr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    private <T> String beanToString(T value){

        if(value==null){
            return null;
        }
        Class<?> clazz=value.getClass();
        if(clazz==int.class||clazz==Integer.class){
            return ""+value;
        }else if(clazz==String.class){
            return(String)value;
        }else if(clazz==long.class||clazz==Long.class){
            return ""+value;
        }else {
            return JSON.toJSONString(value);
        }
    }

    @SuppressWarnings("unchecked")
    private <T> T stringToBean(String str,Class<T> clazz){
        if(str==null||str.length()<=0||clazz==null){
            return null;
        }
        if(clazz==int.class||clazz==Integer.class){
            return (T)Integer.valueOf(str);
        }else if(clazz==String.class){
            return (T) str;
        }else if(clazz==long.class||clazz==Long.class){
            return (T)Long.valueOf(str);
        }else {
            return JSON.toJavaObject(JSON.parseObject(str), clazz);
        }
    }

    private void returnToPool(Jedis jedis){
        if(jedis!=null){
            jedis.close();
        }
    }

}

 运行结果