Redis如何存储对象与集合示例详解

2020-10-28 21:33:56

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前言

大家都知道在项目中，缓存以及mq消息队列可以说是不可或缺的2个重要技术。前者主要是为了减轻数据库压力，大幅度提升性能。后者主要是为了提高用户的体验度，我理解的是再后端做的一个ajax请求(异步)，并且像ribbmitmq等消息队列有重试机制等功能。

这里主要讲redis如何把对象，集合存入，并且取出。下面话不多说了，来一起看看详细的介绍吧。

1.在启动类上加入如下代码

private Jedis jedis;private JedisPoolConfig config;private JedisShardInfo sharInfo;@Beanpublic Jedis jedis(){//连接redis服务器，192.168.0.100:6379// jedis = new Jedis("192.168.0.100", 6379);// //权限认证// jedis.auth("123456");// 操作单独的文本串config = new JedisPoolConfig(); config.setMaxIdle(1000);//最大空闲时间config.setMaxWaitMillis(1000); //最大等待时间config.setMaxTotal(500); //redis池中最大对象个数sharInfo = new JedisShardInfo("192.168.0.100", 6379); sharInfo.setPassword("123456"); sharInfo.setConnectionTimeout(5000);//链接超时时间jedis = new Jedis(sharInfo);return jedis; }

2.在application.yml当中加入redis配置

spring:  redis:  database: 0  host: 101.132.191.77  port: 6379  password: 123456  pool:  max-idle: 8 #连接池最大连接数（使用负值表示没有限制）  min-idle: 0 # 连接池中的最小空闲连接  max-active: 8 # 连接池最大阻塞等待时间（使用负值表示没有限制）  max-wait: -1 # 连接池中的最大空闲连接  timeout: 5000 # 连接超时时间（毫秒）

3.新建SerializeUtil类，这个类主要是为了将对象序列化redis当中

import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.ObjectInputStream; import java.io.ObjectOutputStream;/** public class SerializeUtil {  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 (Exception e) {    }return null;  }  public static Object unserialize( byte[] bytes) {  ByteArrayInputStream bais = null;  try {  // 反序列化bais = new ByteArrayInputStream(bytes);  ObjectInputStream ois = new ObjectInputStream(bais);  return ois.readObject();   } catch (Exception e) {    }return null;  }  }

4.我封装了一个RedisServiceImpl类，主要是用对redis设值和取值

import com.ys.util.redis.SerializeUtil; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.redis.core.StringRedisTemplate; import org.springframework.stereotype.Service; import redis.clients.jedis.Jedis; import java.util.List; import java.util.Map; import java.util.concurrent.TimeUnit; @Service public class RedisServiceImpl   {@Autowired   private StringRedisTemplate stringRedisTemplate;  @Autowired  private Jedis jedis;  public void setStr(String key, String value) {  setStr(key, value, null);  }  public void setStr(String key, Object value, Long time)  {if(value == null){  return;  }if(value instanceof String){  String obj = (String) value;  stringRedisTemplate.opsForValue().set(key, obj);  }else if(value instanceof List){  List obj = (List) value;  stringRedisTemplate.opsForList().leftPushAll(key,obj);  }else if(value instanceof Map){  Map obj = (Map) value;  stringRedisTemplate.opsForHash().putAll(key,obj);  }if (time != null)  stringRedisTemplate.expire(key, time, TimeUnit.SECONDS);  }  public Object getKey(String key)  {return stringRedisTemplate.opsForValue().get(key);   }  public void delKey(String key) {  stringRedisTemplate.delete(key);  }  public boolean del(String key)  {return jedis.del(key.getBytes())>0;  } }

5.测试redis是否ok，编写redisController类

import com.ys.service.impl.RedisServiceImpl; import com.ys.vo.IqProduct; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; import java.util.ArrayList; import java.util.Date; import java.util.List; @RestController  public class RedisServiceController   { @Autowired  private RedisServiceImpl redisService; @RequestMapping(value = "/setredis") public String setredis(String keyredis){  redisService.setStr(keyredis,"2018年1月26日");  return "保存成功,请访问getredis查询redis"; } @RequestMapping(value = "/setObj") public String setObj(String keyredis){  IqProduct iqProduct = new IqProduct();  iqProduct.setSort(1);  iqProduct.setTimestamp(new Date().getTime());  iqProduct.setProductName("productname");  // list.add(iqProduct);  redisService.set(keyredis, iqProduct);  return "保存成功,请访问getredis查询redis";  }  @RequestMapping(value = "/getObj")  public Object getObj(String keyredis){  Object object = redisService.get(keyredis);  if(object !=null){  IqProduct iqProduct = (IqProduct) object;  System. out.println(iqProduct.getProductName());  System. out.println(iqProduct.getId());  System. out.println(iqProduct.getTimestamp());  }return object; }  @RequestMapping(value = "/delObj")  public boolean delObj(String keyredis)  {boolean del = redisService.del(keyredis);   return del;  }  @RequestMapping(value = "/getredis")  public String getredis(String keyredis){  String getredis = (String) redisService.getKey(keyredis);  return "redis的key是===>"+getredis;  }  @RequestMapping(value = "/delredis")  public String delredis(String keyredis){  redisService.delKey(keyredis);  return "删除成功，请通过getredis进行查询";  }  @RequestMapping(value = "/setList")  public String setList(String keyredis){  List list = new ArrayList();for (int i = 0;i<10;i++){  IqProduct iqProduct = new IqProduct();  iqProduct.setSort(1);  iqProduct.setTimestamp(new Date().getTime());  iqProduct.setProductName("productname");  list.add(iqProduct);  }  redisService.set(keyredis, list);  return "保存成功,请访问getredis查询redis";  }  @RequestMapping(value = "/getList")  public Object getList(String keyredis){  Object object = redisService.get(keyredis);  if(object !=null){  List<IqProduct> iqProducts = (List<IqProduct>) object;  for (int i = 0;i<iqProducts.size();i++){  IqProduct iqProduct = iqProducts.get(i);  System. out.println(iqProduct.getProductName());  System. out.println(iqProduct.getId());  System. out.println(iqProduct.getTimestamp());  }  }return object;  }  @RequestMapping(value = "/delList")  public boolean delList(String keyredis)  {  boolean del = redisService.del(keyredis);return del;  } }

6.测试结果