新增依賴

由於redis快取是公共應用，所以我們把依賴與配置新增到了common模組下面，在common模組pom.xml下新增以下依賴

<!-- redis -->
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

<!-- spring2.X整合redis所需common-pool2-->
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-pool2</artifactId>
    <version>2.6.0</version>
</dependency>
 

配置

配置類

在service-base模組新增redis配置類，固定寫法，貼上即可

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.RedisSerializationContext;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;

import java.time.Duration;

@EnableCaching //開啟快取
@Configuration  //配置類
public class RedisConfig extends CachingConfigurerSupport {

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {
        RedisTemplate<String, Object> template = new RedisTemplate<>();
        RedisSerializer<String> redisSerializer = new StringRedisSerializer();
        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.setConnectionFactory(factory);
        //key序列化方式
        template.setKeySerializer(redisSerializer);
        //value序列化
        template.setValueSerializer(jackson2JsonRedisSerializer);
        //value hashmap序列化
        template.setHashValueSerializer(jackson2JsonRedisSerializer);
        return template;
    }

    @Bean
    public CacheManager cacheManager(RedisConnectionFactory factory) {
        RedisSerializer<String> redisSerializer = new StringRedisSerializer();
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        //解決查詢快取轉換異常的問題
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(om);
        // 配置序列化（解決亂碼的問題）,過期時間600秒
        RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig()
                .entryTtl(Duration.ofSeconds(600))
                .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer))
                .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer))
                .disableCachingNullValues();
        RedisCacheManager cacheManager = RedisCacheManager.builder(factory)
                .cacheDefaults(config)
                .build();
        return cacheManager;
    }
}

 

使用redis模組配置

在使用到redis的模組的配置檔案application.properties中新增redis配置

spring.redis.host=192.168.44.132
spring.redis.port=6379
spring.redis.database= 0
spring.redis.timeout=1800000

spring.redis.lettuce.pool.max-active=20
spring.redis.lettuce.pool.max-wait=-1
#最大阻塞等待時間(負數表示沒限制)
spring.redis.lettuce.pool.max-idle=5
spring.redis.lettuce.pool.min-idle=0
 

linux中redis配置

1. 關閉防火牆

   #1:檢視防火狀態
   systemctl status firewalld
   service  iptables status
   
   #2:暫時關閉防火牆
   systemctl stop firewalld
   service  iptables stop
   
   #3:永久關閉防火牆
   systemctl disable firewalld
   chkconfig iptables off
   
   #4:重啟防火牆
   systemctl enable firewalld
   service iptables restart  
   

2. redis配置檔案

   1.註釋掉bind 127.0.0.1
   
   2.修改protected-mode yes 為 protected-mode no
   

使用

由於首頁資料變化不是很頻繁，而且訪問量相對較大，所以我們有必要把首頁介面資料快取到redis快取中，減少資料庫壓力和提高訪問速度改造service-cms模組首頁banner介面，首頁課程與講師介面類似

springboot註解

快取@Cacheable

根據方法對其返回結果進行快取，下次再請求時，如果有快取，則直接讀取快取資料返回；如果快取不存在，則執行方法，並把返回的結果存入快取中。一般用在查詢方法上。

屬性值如下：

快取@CachePut

使用該註解標誌的方法，每次都會執行，並將結果存入指定的快取中。其他方法可以直接從響應的快取中讀取快取資料，而不需要再去查詢資料庫。一般用在新增方法上。

屬性值如下：

快取@CacheEvict

使用該註解標誌的方法，會清空指定的快取。一般用在更新或者刪除方法上

在service方法上使用註解

    @Cacheable(value = "banner", key = "'selectIndexList'")
    @Override
    public List<CrmBanner> selectAllBanner() {
        QueryWrapper<CrmBanner> wrapper = new QueryWrapper<>();
        wrapper.orderByDesc("id");
        wrapper.last("limit 2");
        List<CrmBanner> list = baseMapper.selectList(wrapper);
        return list;
    }

keys *檢視redis是否存入

可以看到值已存入redis