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简介

• Spring Cache是一个框架，实现了基于注解的缓存功能
• 底层可以使用EHCache、Caffeine、Redis实现缓存。

注解一般放在Controller的方法上，@CachePut 注解一般有两个参数，第一个时存储的名称，第二个时名称后边的key，使用SpEL动态的计算key。其余的注解也都是这两个参数。在用户端的查询操作需要使用@Cacheable，服务器端的增删改都使用@CacheEvict

引入依赖

SpringCache
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-cache</artifactId>
</dependency>Redis
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>mysql
<dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope>
</dependency>mybatis
<dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>2.2.0</version>
</dependency>

application.yml配置

server:port: 8888
spring:datasource:druid:driver-class-name: com.mysql.cj.jdbc.Driverurl: jdbc:mysql://localhost:3306/test?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull&useSSL=false&allowPublicKeyRetrieval=trueusername: rootpassword: 123456redis:host: localhostport: 6379password: 123456database: 1
logging:level:com:itheima:mapper: debugservice: infocontroller: info

常用注解

使用

1. 启动类添加注解

package com.itheima;import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;@Slf4j
@SpringBootApplication
-----------------------------------------
添加下面的注解
@EnableCaching
-----------------------------------------
public class CacheDemoApplication {public static void main(String[] args) {SpringApplication.run(CacheDemoApplication.class,args);log.info("项目启动成功...");}
}

使用方法上添加注解

package com.itheima.controller;import com.itheima.entity.User;
import com.itheima.mapper.UserMapper;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.web.bind.annotation.*;@RestController
@RequestMapping("/user")
@Slf4j
public class UserController {@Autowiredprivate UserMapper userMapper;/*** 新增方法返回值放入缓存*/@PostMapping//参数1，缓存名称，参数2，动态获取方法参数字段//最总保存效果是 [参数1::参数2]。例如[userCache::1]@CachePut(cacheNames = "userCache", key = "#user.id")//也可以这样写，参数2不再是方法参数，而是方法的返回值//@CachePut(cacheNames = "userCache",key = "#result.id")//也可以这样写，p0代表第一个参数，p1代表第二个参数//@CachePut(cacheNames = "userCache", key = "#p0.id")public User save(@RequestBody User user) {userMapper.insert(user);return user;}//删除  userCache::id@CacheEvict(cacheNames = "userCache", key = "#id")@DeleteMappingpublic void deleteById(Long id) {userMapper.deleteById(id);}//删除 所有的 userCache::*@CacheEvict(cacheNames = "userCache", allEntries = true)@DeleteMapping("/delAll")public void deleteAll() {userMapper.deleteAll();}//cache生成 userCache::id@Cacheable(cacheNames = "userCache", key = "#id")@GetMappingpublic User getById(Long id) {User user = userMapper.getById(id);return user;}}