SpringBoot+Mybatis+Redis 实现缓存

缺乏、安全感 2022-05-26 07:30 168阅读 0赞

搭建环境：

IDEA，jdk1.8，springboot1.5.3

新建springboot项目  依赖选择如下

![70][]

springboot的推荐项目结构如下

![70 1][]

其中

*  root package结构：com.example.myproject
 *  应用主类Application.java置于root package下，通常我们会在应用主类中做一些框架配置扫描等配置， 我们放在root package下可以帮助程序减少手工配置来加载到我们希望被Spring加载的内容
 *  实体（Entity）与数据访问层（Repository）置于com.example.myproject.domain包下
 *  逻辑层（Service）置于com.example.myproject.service包下
 *  Web层（web）置于com.example.myproject.web包下

搭建完的项目结构如下

![70 2][]

**本文采用mybatis-generator自动生成mapper，dao，entity，**具体操作步骤见

[https://blog.csdn.net/sinat\_29774479/article/details/78542626][https_blog.csdn.net_sinat_29774479_article_details_78542626]  Intellji IDE使用mybatis-generator自动生成mybatis相关文件

删除application.properties  新建application.yml,

**server:**

**    port:** 8080

**spring:**

**    datasource:**

**        name:** test

**        url:** jdbc:mysql://127.0.0.1:3306/world

**        username:** root

**        password:** 1234

*        \#* *使用* *druid* *数据源*

**        type:** com.alibaba.druid.pool.DruidDataSource

**        driver-class-name:** com.mysql.jdbc.Driver

**        filters:** stat

**        maxActive:** 20

**        initialSize:** 1

**        maxWait:** 60000

**        minIdle:** 1

**        timeBetweenEvictionRunsMillis:** 60000

**        minEvictableIdleTimeMillis:** 300000

**        validationQuery:** select 'x'

**        testWhileIdle:** true

**        testOnBorrow:** false

**        testOnReturn:** false

**        poolPreparedStatements:** true

**        maxOpenPreparedStatements:** 20

**redis:**

**    host:** 171.188.96.88

**    port:** 6379

**    password:** root

**mybatis:**

**    mapper-locations:** classpath:mapper/\*.xml

**    type-aliases-package:** com.redis.domain

*\#pagehelper* *分页插件*

**pagehelper:**

**    helperDialect:** mysql

**    reasonable:** true

**    supportMethodsArguments:** true

**    params:** count=countSql

添加redis的配置类,继承CachingConfigurerSupport根据自己需要重写方法

**package** com.redis.config;

**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.cache.interceptor.KeyGenerator;

**import** org.springframework.context.annotation. Bean ;

**import** org.springframework.context.annotation. Configuration ;

**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.core.StringRedisTemplate;

**import** org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;

**import** java.lang.reflect.Method;

*/\*\**

*\* Redis* *缓存配置类*

*\**

*\** ***@author*** *wl*

*\*/*

@Configuration

@EnableCaching

**public class** RedisConfig **extends** CachingConfigurerSupport \{

*/\** *定义缓存数据* *key* *生成策略的* *bean*

*包名* *+* *类名* *+* *方法名* *+* *所有参数*

*\*/*

@Bean

**public** KeyGenerator wiselyKeyGenerator() \{

**return new** KeyGenerator() \{

@Override

**public** Object generate(Object target, Method method, Object... params) \{

StringBuilder sb = **new** StringBuilder();

sb.append(target.getClass().getName());

sb.append(method.getName());

**for** (Object obj : params) \{

sb.append(obj.toString());

**return** sb.toString();

\};

*/\** *要启用* *spring* *缓存支持* *,* *需创建一个* *CacheManager* *的* *bean* *，* *CacheManager* *接口有很多实现，这里* *Redis* *的集成，用* *RedisCacheManager* *这个实现类*

*Redis* *不是应用的共享内存，它只是一个内存服务器，就像* *MySql* *似的，*

*我们需要将应用连接到它并使用某种* *“* *语言* *”* *进行交互，因此我们还需要一个连接工厂以及一个* *Spring* *和* *Redis* *对话要用的* *RedisTemplate* *，*

*这些都是* *Redis* *缓存所必需的配置，把它们都放在自定义的* *CachingConfigurerSupport* *中*

*\*/*

@Bean

**public** CacheManager cacheManager(

@SuppressWarnings ( **"rawtypes"** ) RedisTemplate redisTemplate) \{

RedisCacheManager cacheManager = **new** RedisCacheManager(redisTemplate);

*// cacheManager.setDefaultExpiration(60);//* *设置缓存保留时间（* *seconds* *）*

**return** cacheManager;

*//1.* *项目启动时此方法先被注册成* *bean* *被* *spring* *管理*

@Bean

**public** RedisTemplate<String, String> redisTemplate(

RedisConnectionFactory factory) \{

StringRedisTemplate template = **new** StringRedisTemplate(factory);

Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = **new** Jackson2JsonRedisSerializer(Object. **class** );

ObjectMapper om = **new** ObjectMapper();

om.setVisibility(PropertyAccessor. ***ALL*** , JsonAutoDetect .Visibility. ***ANY*** );

om.enableDefaultTyping(ObjectMapper.DefaultTyping. ***NON\_FINAL*** );

jackson2JsonRedisSerializer.setObjectMapper(om);

template.setValueSerializer(jackson2JsonRedisSerializer);

template.afterPropertiesSet();

**return** template;

新建controller

**package** com.redis.controller;

**import** com.redis.service.CityService;

**import** org.springframework.beans.factory.annotation. Autowired ;

**import** org.springframework.boot.autoconfigure. EnableAutoConfiguration ;

**import** org.springframework.web.bind.annotation. RequestMapping ;

**import** org.springframework.web.bind.annotation. ResponseBody ;

**import** org.springframework.web.bind.annotation. RestController ;

@RestController

@EnableAutoConfiguration

@RequestMapping ( **"/query"** )

**public class** CityController \{

@Autowired

**private** CityService **cityService** ;

@ResponseBody

@RequestMapping ( **"/findAll"** )

**public** Object findAll() \{

**return** **cityService** .selectAllCity();

在CityMapper.xml中加入

< **select** **id** **="selectAllCity"** **resultMap** **="BaseResultMap"** >

select

< **include** **refid** **="Base\_Column\_List"** />

from city

</ **select** >

新建service

**package** com.redis.service;

**import** com.redis.domain.City;

**import** java.util.List;

**public interface** CityService \{

List<City> selectAllCity();

实现service接口

**package** com.redis.service;

**import** com.redis.dao.CityMapper;

**import** com.redis.domain.City;

**import** org.springframework.beans.factory.annotation. Autowired ;

**import** org.springframework.cache.annotation. Cacheable ;

**import** org.springframework.stereotype. Service ;

**import** java.util.List;

@Service (value = **"cityService"** )

**public class** CityServiceImpl **implements** CityService \{

@Autowired

**private** CityMapper **cityMapper** ;

@Override

@Cacheable (value = **"all"** , keyGenerator = **"wiselyKeyGenerator"** )

**public** List<City> selectAllCity() \{

**return** **cityMapper** .selectAllCity();

查看redis数据库,发现第二次查询时间大幅减少，且出现配置中的缓存

![70 3][]

[70]: /images/20220526/5ec704faddd64fc7889cacfcfb5106ed.png
[70 1]: /images/20220526/5509f979058f43e3b0e225d0788e0003.png
[70 2]: /images/20220526/c8997964e27f4b8ca3dd2269bcb1e336.png
[https_blog.csdn.net_sinat_29774479_article_details_78542626]: https://blog.csdn.net/sinat_29774479/article/details/78542626
[70 3]: /images/20220526/688321d937264c20b87595a2377842ad.png