主要实现一个商品秒杀的功能，梳理如何应对高并发的的技术的思路。
1.后端：SpringBoot、JSR303、MyBatis
2.前端：Thymeleaf、BootStrap、Jquery
3.中间件：RabbitMQ、Redis、Druid
1.添加maven
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.9.RELEASE</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
</dependencies>
1.导入依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
2.添加配置项：
spring.thymeleaf.cache=false
spring.thymeleaf.content-type=text/html
spring.thymeleaf.enabled=true
spring.thymeleaf.encoding=UTF-8
spring.thymeleaf.mode=HTML5
spring.thymeleaf.prefix=classpath:/templates/
spring.thymeleaf.suffix=.html
3.添加thymeleaf模版
<!DOCTYPE HTML>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<title>hello</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body>
<p th:text="'hello:'+${name}" ></p>
</body>
</html>
1.添加依赖
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.1</version>
</dependency>
2.添加配置
# mybatis
mybatis.type-aliases-package=com.chengxiaoxiao.seckillshop.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/chengxiaoxiao/seckillshop/dao/*.xml
1.添加依赖
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.5</version>
</dependency>
2.添加配置
spring.datasource.url=jdbc:mysql://localhost:3306/miaosha?useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true&useSSL=false&serverTimezone=GMT%2B8
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.filters=stat
spring.datasource.maxActive=2
spring.datasource.initialSize=1
spring.datasource.maxWait=60000
spring.datasource.minIdle=1
spring.datasource.timeBetweenEvictionRunsMillis=60000
spring.datasource.minEvictableIdleTimeMillis=300000
spring.datasource.validationQuery=select 'x'
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
spring.datasource.poolPreparedStatements=true
spring.datasource.maxOpenPreparedStatements=20
logging.leve.com.chengxiaoxiao.seckillshop=debug
1.官网：https://redis.io/download
2.解压安装：
1.解压文件：tar -zxvf redis-5.0.0.tar.gz
2.移动到安装目录：mv redis-5.0.0 /usr/local/redis
3.编译一下：make -j 4
编译依赖gcc，安装如下：
1.yum install gcc
2.验证是否安装成功：rpm -qa |grep gcc
4.make install
5.修改配置文件
vi redis.config
1.修改可访问IP：修改bind 127.0.0.1 为bind 0.0.0.0
2.修改后台启用：daemonize yes
3.添加密码：requirepass
6.运行：redis-server ./redis.conf
7.重启：redis-cli shutdown save
8.命令行登录：auth password
9.修改redis为系统服务
1.cd utils
2. ./install_server.sh
config: /usr/local/redis/redis.config
log: /usr/local/redis/redis.log
data: /usr/local/redis/data
10.查看后台进程是否存在
1.查看进程：ps -ef |grep redis
2.端口是否在监听：netstat -lntp | grep 6379
3.添加依赖
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.38</version>
</dependency>
4.添加配置：
#redis
redis.host=192.168.220.128
redis.port=6379
redis.timeout=3
redis.password=123456
redis.poolMaxTotal=10
redis.poolMaxIdle=10
redis.poolMaxWait=3
- 获取zone名称：firewall-cmd --get-active-zones
- 执行防火墙开启端口：firewall-cmd --zone=public --add-port=6379/tcp --permanent
- 重启防火墙：firewall-cmd --reload
- 查看端口是否开启：firewall-cmd --query-port=6379/tcp
- 查看服务：chkconfig --list | grep redis
- 添加依赖：
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.6</version>
</dependency>
2.调用方法：
DigestUtils.md5Hex(src);
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>
1.添加注解类实现方法，注解类模板：
@Target({ METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER })
@Retention(RUNTIME)
@Documented
@Constraint(validatedBy = {IsMobileValidator.class })
public @interface IsMobile {
String message() default "手机号码格式错误";
Class<?>[] groups() default { };
Class<? extends Payload>[] payload() default { };
}
2.添加注解校验规则类
public class IsMobileValidator implements ConstraintValidator<IsMobile, String> {
@Override
public void initialize(IsMobile constraintAnnotation) {
}
@Override
public boolean isValid(String s, ConstraintValidatorContext constraintValidatorContext) {
return true;
}
}
2.使用
Vo对应属性上增加注解，实现校验
1.自定义类，继承自WebMvcConfigurerAdapter，并添加@Configuration注解,使用参数解析器，重写addArgumentResolvers方法，添加自定义的解析器
2.自定义参数解析器，实现HandlerMethodArgumentResolver接口，重写supportsParameter和resolveArgument。
3.这样就可以直接在参数中增加对应的user，直接获取值了
3.修改界面为中文：
找到jmeter下的bin目录，打开jmeter.properties 文件
第三十七行修改为
language=zh_CN
3.基本步骤：
1.添加线程组
2.添加HTTP请求配置器：
1.添加依赖
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
<scope>provided</scope>
</dependency>
2.添加plugins
<build>
<finalName>${project.artifactId}</finalName>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
3.修改打包方式为war
<packaging>war</packaging>
4.mainApplication需要继承SpringBootServletInitializer,并重写configure方法
@Override
protected SpringApplicationBuilder configure(SpringApplicationBuilder builder) {
return builder.sources(MainApplication.class);
}
5.项目根目录打包：mvn clean package 6.放tomcat目录下，启动（解决需要增加应用名） 1.可以把context设置为空 2.直接放到ROOT目录下
一、页面缓存
把页面渲染好的页面缓存放入redis
实现代码：
1.SpringBoot 2.0写法
//取缓存
WebContext ctx = new WebContext(request, response, request.getServletContext(), request.getLocale(), model.asMap());
html = thymeleafViewResolver.getTemplateEngine().process("goodlist", ctx);
if (!StringUtils.isEmpty(html)) {
redisService.set(GoodsKey.getGoodList, "", html);
}
2.SpringBoot 1.0写法
SpringWebContext context = new SpringWebContext(request,response,request.getServletContext(),request.getLocale(),model.asMap(),applicationContext);
String html = thymeleafViewResolver.getTemplateEngine().process("goods_list",context);
二、对象缓存
1.在Service中，取Dao的数据时，先取redis的数据，如果redis中没有才取数据库的数据。 当数据库数据修改时，自动修改redis的数据
三、页面静态化
1.vue，angular进行页面静态化，减少服务器请求
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
添加maven后，会自动添加热部署功能。但需要进行重新编译才可以实现更新
1.JS/CSS压缩
2.多个CSS/JS合并，减少链接
1.安装erlong
1.安装依赖：
yum install ncurses-devel
2.下载erlang包，编译安装
1)http://www.erlang.org/downloads
2)
2.安装RabbitMQ
1.下载地址：http://www.rabbitmq.com/install-generic-unix.html
2.
(1).报错
An attempt was made to call the method javax.servlet.ServletContext.getVirtualServerName()Ljava/lang/String; but it does not exist. Its class, javax.servlet.ServletContext, is available from the following locations:
jar:file:/Users/ac/.gradle/caches/modules-2/files-2.1/javax.servlet/servlet-api/2.4/3fc542fe8bb8164e8d3e840fe7403bc0518053c0/servlet-api-2.4.jar!/javax/servlet/ServletContext.class
jar:file:/Users/ac/.gradle/caches/modules-2/files-2.1/org.apache.tomcat.embed/tomcat-embed-core/8.5.34/a038040d68a90397f95dd1e11b979fe364a5000f/tomcat-embed-core-8.5.34.jar!/javax/servlet/ServletContext.class
(2).解决：servlet-api版本太低，升级即可，
1.下载tomcat.zip包（https://tomcat.apache.org/download-80.cgi），
2.找到lib/servlet-api.jar，复制到java jdk目录下/jre/lib/ext下