redis是如何存储对象和集合的

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.

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

redisServiceImpl.set主要是传object,setStr主要设置string

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

image.png

7.参考文章

Springboot+Redis 配置和使用