pom.xml：
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!--redis-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>application.properties：
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/hrms?useUnicode=true&characterEncoding=utf8&useSSL=true&serverTimezone=GMT
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.jpa.database=mysql
#自动建表
spring.jpa.hibernate.ddl-auto=update
#设置数据库方言
spring.jpa.database-platform=org.hibernate.dialect.MySQL5InnoDBDialect
#打印sql
spring.jpa.show-sql=true
# Redis数据库索引（默认为0）
spring.redis.database=0
# Redis服务器地址
spring.redis.host=127.0.0.1
# Redis服务器连接端口
spring.redis.port=6379
# Redis服务器连接密码（默认为空）
spring.redis.password=123456
# 连接池最大连接数（使用负值表示没有限制）
spring.redis.jedis.pool.max-active=8
# 连接池最大阻塞等待时间（使用负值表示没有限制）
spring.redis.jedis.pool.max-wait=-1ms
# 连接池中的最大空闲连接
spring.redis.jedis.pool.max-idle=8
# 连接池中的最小空闲连接
spring.redis.jedis.pool.min-idle=0
# 连接超时时间（毫秒）
spring.redis.timeout=200msspringboot入口：
package com.example.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;
import springfox.documentation.swagger2.annotations.EnableSwagger2;
/**
*
*
*@author FastKing
*@date 17:42 2018/11/1
*@param
**/
@SpringBootApplication
@EnableSwagger2
@EnableCaching
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
@EnableCaching表示开启缓存
redis配置类：
package com.example.demo.config.redis;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import java.time.Duration;
import java.util.HashMap;
import java.util.HashSet;
/**
* @author FastKing
* @version 1.0
* @date 2018/11/5 11:40
**/
@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport {
@Bean
public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory connectionFactory){
//使用Jackson2JsonRedisSerializer来序列化和反序列化redis的value值
RedisTemplate<Object, Object> redisTemplate = new RedisTemplate<>();
redisTemplate.setConnectionFactory(connectionFactory);
Jackson2JsonRedisSerializer serializer = new Jackson2JsonRedisSerializer(Object.class);
ObjectMapper mapper = new ObjectMapper();
mapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
serializer.setObjectMapper(mapper);
redisTemplate.setValueSerializer(serializer);
//使用StringRedisSerializer来序列化和反序列化redis的key值
redisTemplate.setKeySerializer(new StringRedisSerializer());
redisTemplate.afterPropertiesSet();
return redisTemplate;
}
@Bean
public CacheManager cacheManager(RedisConnectionFactory connectionFactory){
// 生成一个默认配置，通过config对象即可对缓存进行自定义配置
// 不缓存空值
RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig().disableCachingNullValues();
// 设置一个初始化的缓存空间set集合
HashSet<String> cacheNames = new HashSet<>();
cacheNames.add("timeGroup");
cacheNames.add("user");
// 对每个缓存空间应用不同的配置
HashMap<String, RedisCacheConfiguration> configMap = new HashMap<>(2);
// 设置缓存的默认过期时间，也是使用Duration设置
configMap.put("timeGroup",config.entryTtl(Duration.ofMinutes(1)));
configMap.put("user",config.entryTtl(Duration.ofMinutes(1)));
// 使用自定义的缓存配置初始化一个cacheManager
// 注意这两句的调用顺序，一定要先调用该方法设置初始化的缓存名，再初始化相关的配置
return RedisCacheManager.builder(connectionFactory).initialCacheNames(cacheNames).withInitialCacheConfigurations(configMap).build();
}
}
前端index.html：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<div id="userList">
</div>
</body>
<script type="text/javascript" src="/js/jquery-3.3.1.min.js"></script>
<script type="text/javascript">
var obj = window.document.location;
var BASE_PATH = obj.href.substring(0, obj.href.indexOf(obj.pathname));
//请求渲染模拟
$.ajax({
url: BASE_PATH + "/user/list",
type: "get",
success: function f(data) {
$.each(data,function (index, data) {
$("#userList").append(data.username + "：<button onclick='detail("+data.id+")'>查看</button>");
})
}
}),
function detail(id){
$.ajax({
url: BASE_PATH + "/user/detail/"+id,
type: "get",
success: function f(data) {
console.log(data);
}
})
}
</script>
</html>后端Controller：
package com.example.demo.controller;
import com.example.demo.jpa.UserJpa;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
/**
* @ClassName UserController
* @Description TODO
* @Author Fast King
* @Date 2018/11/1 21:58
* @Version 1.0
**/
@RestController
@RequestMapping("user")
public class UserController {
@Autowired
private UserJpa userJpa;
@GetMapping("list")
public Object list(){
return userJpa.findAll();
}
@GetMapping("detail/{id}")
@Cacheable(value = "user" , key = "#id" , condition = "#result eq null ")
public Object detail(@PathVariable Integer id){
return userJpa.findById(id);
}
}
@Cacheable为spring中的缓存注解
redis是个键值对数据库
value为你在redis配置类中设置的缓存空间名称，key为redis的键，condition为执行下面方法的条件
使用了该注解的方法，会优先从redis中找对应数据，如果redis中有则直接返回，如果没有再执行方法从数据库中找。
看一下效果：
我们点一下查看
控制台打印了sql
再点查看，控制台就没有打印了。
过一分钟后，redis缓存失效，再点查看，控制台就又打印了
说明redis缓存成功