springboot整合redis

springboot整合redis

springboot2.x之后原来底层操作redis使用的jedis被替换成了lettuce

jedis：采用直连，多个线程同时操作是不安全的，如果想要避免不安全，就要使用jedis pool连接池，但是比较麻烦，类似BIO模式

lettuce：采用netty，实例可以在多个线程中进行共享，不存在线程不安全的情况，可以减少线程数据，类似NIO模式

• springboot知识回顾

所有的配置类，都有一个自动配置类，自动配置类都会绑定一个properties文件

我们可以找到springboot自动配置类的jar包里的META-INF下的spring.factories文件查看redis自动配置类源码

• 源码简单说明：

@Configuration(proxyBeanMethods = false)
@ConditionalOnClass(RedisOperations.class)
@EnableConfigurationProperties(RedisProperties.class)
@Import({ LettuceConnectionConfiguration.class, JedisConnectionConfiguration.class })
public class RedisAutoConfiguration {

    /**
     * 默认的redisTemplate,我们可以自定义一个redisTemplate来替换这个
     */
	@Bean
	@ConditionalOnMissingBean(name = "redisTemplate")
	@ConditionalOnSingleCandidate(RedisConnectionFactory.class)
	public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {
        // 默认的redisTemplate没有过多的设置,但是redis对象都是需要序列化的
        // 两个泛型都是object类型,我们使用的时候需要强制转换
		RedisTemplate<Object, Object> template = new RedisTemplate<>();
		template.setConnectionFactory(redisConnectionFactory);
		return template;
	}

    /**
     * 由于string类型是redis中最常用的,所以单独提供了一个bean
     */
	@Bean
	@ConditionalOnMissingBean
	@ConditionalOnSingleCandidate(RedisConnectionFactory.class)
	public StringRedisTemplate stringRedisTemplate(RedisConnectionFactory redisConnectionFactory) {
		StringRedisTemplate template = new StringRedisTemplate();
		template.setConnectionFactory(redisConnectionFactory);
		return template;
	}

}

代码实战

导包

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-pool2</artifactId>
    <version>2.6.0</version>
</dependency>

配置文件

spring:
  redis:
    # redis服务器ip
    host: 192.168.84.136
    # redis服务端口号
    port: 6379
    # redis数据库索引
    database: 0
    # redis密码,如果redis没有配置需要密码这里就不用配置
    password: 123456
    # 连接超时时间
    timeout: 17000
    lettuce:
      pool:
        # 连接池最大数,使用负值表示没有限制
        max-active: 20
        # 连接池最大阻塞等待时间
        max-wait: -1
        # 连接池最大空闲连接数
        max-idle: 5
        # 连接池最小空闲连接数
        min-idle: 0

redis配置类

package com.yl.redisd.springboot.guigu.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.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;

/**
 * redis配置类
 *
 * @author Y-wee
 */
@Configuration
// 开启缓存
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport {

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory factory) {
        RedisTemplate<String, Object> template = new RedisTemplate<>();
        // String类型序列化对象
        RedisSerializer<String> redisSerializer = new StringRedisSerializer();
        // jackson序列化对象
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);

        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(objectMapper);

        template.setConnectionFactory(factory);
        // key序列化方式
        template.setKeySerializer(redisSerializer);
        template.setHashKeySerializer(redisSerializer);
        // value序列化方式
        template.setValueSerializer(jackson2JsonRedisSerializer);
        // hash类型的value序列化方式
        template.setHashValueSerializer(jackson2JsonRedisSerializer);

        return template;
    }

    @Bean
    public CacheManager cacheManager(RedisConnectionFactory factory) {
        RedisSerializer<String> redisSerializer = new StringRedisSerializer();
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);

        // 解决查询缓存转换异常的问题
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(objectMapper);

        // 配置序列化(解决乱码的问题),过期时间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;
    }
}

controller

package com.yl.redisd.springboot.guigu.controller;

import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;

/**
 * redis接口
 *
 * @author Y-wee
 */
@RestController
@RequestMapping("/redis")
public class RedisController {
    @Resource
    private RedisTemplate redisTemplate;

    @GetMapping("/get")
    public String get(){
        // 插入String类型键值对到redis
        redisTemplate.opsForValue().set("name","lucy");
        // 从redis获取值
        String name = (String)redisTemplate.opsForValue().get("name");
        return name;
    }

}

浏览器访问：http://localhost:8080/redis/get 返回lucy