Redis怎么存储对象

一时失言乱红尘 2023-01-06 01:38 110阅读 0赞

### 在以往面试中，多次被问到Redis怎么存储对象，我支支吾吾半天回答不上来，毕竟我只用过String类型，为了避免以后的尴尬，今天花点时间来整理一下。 ###

本人用的Jedis客户端

### 首先引入依赖 ###

<dependency>
                <groupId>redis.clients</groupId>
                <artifactId>jedis</artifactId>
                <version>3.2.0</version>
            </dependency>

### 创建一个Jedis实例 ###

package com.xiateng.util;
    
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import redis.clients.jedis.Jedis;
    import redis.clients.jedis.JedisPool;
    import redis.clients.jedis.JedisPoolConfig;
    
    /**
     * jedis获取工具类
     */
    public class JedisUtil {
    
        private static JedisPool jedisPool;
        private static final Logger logger = LoggerFactory.getLogger(JedisUtil.class);
    
        static {
            // 初始化连接池
            JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
            jedisPoolConfig.setMaxTotal(20);
            jedisPoolConfig.setMaxIdle(10);
            jedisPool = new JedisPool(jedisPoolConfig, "127.0.0.1", 6379);
            logger.info("jedisPool连接池初始化====" + jedisPool);
        }
    
        /**
         * 获取一个Jedis实例
         * @return
         */
        public synchronized static Jedis getJedis(){
            Jedis jedis = jedisPool.getResource();
    //        jedis.auth("123456");//密码
            return jedis;
        }
    }

下面我们来实现存储对象

### 方式一：将对象转化为JSON字符串存入redis ###

Jedis jedis = JedisUtil.getJedis();
            TUser tUser = new TUser();
            tUser.setUserName("你好");
            tUser.setPassword("2342342");
            jedis.set("xiateng", JSON.toJSONString(tUser));
    
            String sss = jedis.get("xiateng");
            TUser ssss = JSON.parseObject(sss,TUser.class);
            jedis.del("xiateng");
            System.out.println("---------------------------:  "+ssss.toString());

### 方式二：将对象序列化后存到redis ###

封装序列化跟反序列化方法

package com.xiateng.util;
    
    import java.io.*;
    
    public class SerializeUtil {
    
        /**
         * 序列化操作
         * @param object
         * @return
         */
        public static byte[] serialize(Object object){
            ObjectOutputStream oos = null;
            ByteArrayOutputStream baos = null;
            try {
                // 序列化
                baos = new ByteArrayOutputStream();
                oos = new ObjectOutputStream(baos);
    
                oos.writeObject(object);
                byte[] bytes = baos.toByteArray();
                return bytes;
            } catch (IOException e) {
                e.printStackTrace();
            }
    
            return null;
        }
    
        /**
         * 反序列化操作
         * @param bytes
         * @return
         */
        public static Object unSerialize(byte[] bytes){
            ByteArrayInputStream bais = null;
    
            try {
                bais = new ByteArrayInputStream(bytes);
                ObjectInputStream ois = new ObjectInputStream(bais);
                return ois.readObject();
            } catch (IOException e) {
                e.printStackTrace();
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }
    
            return null;
        }
    }

保存对象

Jedis jedis = JedisUtil.getJedis();      
            jedis.set("code".getBytes(), SerializeUtil.serialize(tUser));
            byte[] bytes = jedis.get("code".getBytes());
            TUser o = (TUser)SerializeUtil.unSerialize(bytes);
            jedis.del("code");
            System.out.println(o.toString());

### 方式三：将对象用Hash数据类型存储 ###

Jedis jedis = JedisUtil.getJedis();
            jedis.hset("user", "id", "3");
            jedis.hset("user", "name", "xiateng");
            jedis.hset("user", "password", "123455");
            jedis.hget("user","id");
            List<String> user = jedis.hmget("user", new String[]{"id","name","password"});
            System.out.println("---------------------------:  "+user);
    
    
            // 输出结果 [3,xiateng,123455]

注意：以序列化的方式存储的对象需要实现 Serializable 接口