引入redis缓存+本地缓存示例（Guava实现）

项目结构

流程

先调用本地缓存进行查找，没有查看redis缓存，没有查数据库，同时添加到redis和本地缓存中

代码

StudentServiceImpl

package com.wunaiieq.tmp_redis_20241217.service;import com.wunaiieq.tmp_redis_20241217.entity.Student;
import com.wunaiieq.tmp_redis_20241217.mapper.StudentMapper;
import lombok.SneakyThrows;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.google.common.cache.*;
import org.springframework.data.redis.core.RedisTemplate;import java.util.concurrent.TimeUnit;@Service
public class StudentServiceImpl implements StudentService{@Autowiredprivate StudentMapper studentMapper;@Autowiredprivate RedisService redisService;/*** 本地缓存*/private LoadingCache<String, Student> Cache = CacheBuilder.newBuilder()//设置并发级别为16，并发级别是指可以同时写缓存的线程数.concurrencyLevel(16)//设置缓存容器的初始容量为1000.initialCapacity(1000)//设置缓存最大容量为10000，超过10000之后就会按照LRU最近虽少使用算法来移除缓存项.maximumSize(10000)//设缓存1小时没被使用就过期.expireAfterAccess(1, TimeUnit.HOURS)//设置要统计缓存的命中率.recordStats()//设置缓存的移除通知.removalListener(new RemovalListener<Object, Object>() {@Overridepublic void onRemoval(RemovalNotification<Object, Object> notification) {System.out.println(notification.getKey() + " 被移除了，原因： " + notification.getCause());}}).build(new CacheLoader<String, Student>() {@Overridepublic Student load(String key) throws Exception {// 如果没有缓存先从redis中获取Student student0 = (Student) redisService.get("user:" + key);if (student0 != null) {return student0;}// 2、redis中没有查询数据库Student student = studentMapper.selectById(key);// 4、加入redis分布式缓存redisService.set("student:" + key, student);return student;}});/*** 根据用户id查询用户** @param id* @return*/@SneakyThrows@Overridepublic Student getById(Long id) {// 1、从本地缓存获取Student o = Cache.get(id + "");return o;}
}

RedisService、RedisConfig
博客链接

Controller

package com.wunaiieq.tmp_redis_20241217.controller;import com.wunaiieq.tmp_redis_20241217.entity.Student;
import com.wunaiieq.tmp_redis_20241217.service.StudentService;
import com.wunaiieq.tmp_redis_20241217.service.StudentServiceImpl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
public class Studentcontroller {@Autowiredprivate StudentServiceImpl studentServiceImpl;@GetMapping("/getByid")public Student getStudent(long id){return studentServiceImpl.getById(id);}
}

StudentService

package com.wunaiieq.tmp_redis_20241217.service;import com.wunaiieq.tmp_redis_20241217.entity.Student;
import lombok.SneakyThrows;public interface StudentService {@SneakyThrowsStudent getById(Long id);
}

StudentMapper

package com.wunaiieq.tmp_redis_20241217.mapper;import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.wunaiieq.tmp_redis_20241217.entity.Student;public interface StudentMapper extends BaseMapper <Student>{
}