Spring boot中使用redis

Redis，英文全称是Remote Dictionary Server（远程字典服务），是一个开源的使用ANSI C语言编写、支持网络、可基于内存亦可持久化的日志型、Key-Value数据库，并提供多种语言的API。

与MySQL数据库不同的是，Redis的数据是存在内存中的。它的读写速度非常快，每秒可以处理超过10万次读写操作。因此redis被广泛应用于缓存，另外，Redis也经常用来做分布式锁。除此之外，Redis支持事务、持久化、LUA 脚本、LRU 驱动事件、多种集群方案。

1.引入依赖

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

2.创建工厂配置

package com.example.demo;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;


@Configuration
public class RedisConfig {
    @Bean
    public RedisConnectionFactory factory(){
        JedisConnectionFactory factory = new JedisConnectionFactory();
        factory.setPort(6379);
        factory.setHostName("localhost");
        return factory;
    }
}

3.使用redis工厂

package com.example.demo;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;



@RestController
public class Test {

    @Autowired
    RedisConnectionFactory factory;

    @GetMapping("/a")
    public String test() {
        RedisConnection connection = factory.getConnection();
        connection.set("a".getBytes(), "aaa".getBytes());
        return new String(connection.get("a".getBytes()));
    }
}

4.使用redis模版

使用上面创建的factory

@Bean
public RedisTemplate redisTemplate(RedisConnectionFactory factory){
    RedisTemplate<String, Object> template = new RedisTemplate<String, Object>();
    template.setConnectionFactory(factory);
    return template;
}

字符串

@RestController
public class Test {

    @Autowired
    RedisTemplate<String, Object> template;

    @GetMapping("/a")
    public String test() {
        template.opsForValue().set("a", "badianboke");
        return template.opsForValue().get("a").toString();
    }
}

集合

UserEntity user1 = new UserEntity();
user1.setName("八点");

UserEntity user2 = new UserEntity();
user1.setName("博客");

template.opsForList().rightPush("abc", user1);
template.opsForList().rightPush("abc", user2);

List<Object> list = template.opsForList().range("abc", 0, template.opsForList().size("abc") - 1);

for (Object obj : list){
    System.out.println(obj);
}

实体类 [ 需要继承 Serializable 接口 ]

package com.example.demo;


import java.io.Serializable;

public class UserEntity implements Serializable {
    public String name;
    public Integer age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}

5.序列化

使用 StringRedisSerializer 序列化和反序列化 key

使用 Jackson2JsonRedisSerializer 序列化和反序列化 value

@Bean
    public RedisTemplate<String,Object> redisTemplate(RedisConnectionFactory redisConnectionFactory){
        //配置redisTemplate
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(redisConnectionFactory);
        // 使用StringRedisSerializer来序列化和反序列化redis的key值
        StringRedisSerializer stringSerializer = new StringRedisSerializer();
        // 用Jackson2JsonRedisSerializer来序列化和反序列化redis的value值
        Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = serializer();

        redisTemplate.setKeySerializer(stringSerializer);//key序列化
        redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);//value序列化
        redisTemplate.setHashKeySerializer(stringSerializer);//Hash key序列化
        redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer);//Hash value序列化
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }

afterPropertiesSet 方法主要是进行设置默认序列化 JdkSerializationRedisSerializer

public void afterPropertiesSet() {
        super.afterPropertiesSet();
        boolean defaultUsed = false;
        if (this.defaultSerializer == null) {
            this.defaultSerializer = new JdkSerializationRedisSerializer(this.classLoader != null ? this.classLoader : this.getClass().getClassLoader());
        }

        if (this.enableDefaultSerializer) {
            if (this.keySerializer == null) {
                this.keySerializer = this.defaultSerializer;
                defaultUsed = true;
            }

            if (this.valueSerializer == null) {
                this.valueSerializer = this.defaultSerializer;
                defaultUsed = true;
            }

            if (this.hashKeySerializer == null) {
                this.hashKeySerializer = this.defaultSerializer;
                defaultUsed = true;
            }

            if (this.hashValueSerializer == null) {
                this.hashValueSerializer = this.defaultSerializer;
                defaultUsed = true;
            }
        }

        if (this.enableDefaultSerializer && defaultUsed) {
            Assert.notNull(this.defaultSerializer, "default serializer null and not all serializers initialized");
        }

        if (this.scriptExecutor == null) {
            this.scriptExecutor = new DefaultScriptExecutor(this);
        }

        this.initialized = true;
    }