SpringMVC项目中如何使用redis缓存技术

r囧r小猫 2023-08-17 15:53 59阅读 0赞

1:电脑上必须安装过Redis，然后启动它。

C:\Users\Administrator>e:
    
    E:\>cd redsi
    系统找不到指定的路径。
    
    E:\>cd redis
    
    E:\redis>redis-server.exe redis.windows.conf
                    _._
               _.-``__ ''-._
          _.-``    `.  `_.  ''-._           Redis 2.8.9 (00000000/0) 64 bit
      .-`` .-```.  ```\/    _.,_ ''-._
     (    '      ,       .-`  | `,    )     Running in stand alone mode
     |`-._`-...-` __...-.``-._|'` _.-'|     Port: 6379
     |    `-._   `._    /     _.-'    |     PID: 1104
      `-._    `-._  `-./  _.-'    _.-'
     |`-._`-._    `-.__.-'    _.-'_.-'|
     |    `-._`-._        _.-'_.-'    |           http://redis.io
      `-._    `-._`-.__.-'_.-'    _.-'
     |`-._`-._    `-.__.-'    _.-'_.-'|
     |    `-._`-._        _.-'_.-'    |
      `-._    `-._`-.__.-'_.-'    _.-'
          `-._    `-.__.-'    _.-'
              `-._        _.-'
                  `-.__.-'
    
    [1104] 27 Sep 11:14:52.263 # Server started, Redis version 2.8.9
    [1104] 27 Sep 11:14:52.310 * DB loaded from disk: 0.047 seconds
    [1104] 27 Sep 11:14:52.310 * The server is now ready to accept connections on port 6379

2：配置Redis的jar包和Spring整合redis的jar包。jar包如下。建议使用下面两个版本的jar包。因为其他版本可能会有版本冲突，导致一系列不能使用问题。

<dependency>
          <groupId>redis.clients</groupId>
          <artifactId>jedis</artifactId>
          <version>2.7.3</version>
        </dependency>
    
        
        <dependency>
          <groupId>org.springframework.data</groupId>
          <artifactId>spring-data-redis</artifactId>
          <version>1.6.2.RELEASE</version>
        </dependency>

3：配置redis.properties以及在Spring-bean.xml中做相关配置

redis.properties

redis.host=127.0.0.1
    redis.port=6379
    redis.password=""
    redis.maxIdle=50
    redis.maxTotal=100
    redis.maxWaitMillis=1000
    redis.blockWhenExhausted=true
    redis.testOnBorrow=true
    redis.timeout=10000
    defaultCacheExpireTime=60

spring-bean.xml,如果在本文件中，已经通过<context:property-placeholder location="redis.properties"/>这种方式导入过其他properties文件，那下面文件中这行可以删去。

<?xml version="1.0" encoding="utf-8" ?>
    <beans xmlns="http://www.springframework.org/schema/beans"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xmlns:context="http://www.springframework.org/schema/context"
           xmlns:aop="http://www.springframework.org/schema/aop"
           xmlns:tx="http://www.springframework.org/schema/tx"
           xsi:schemaLocation="http://www.springframework.org/schema/beans https://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/aop https://www.springframework.org/schema/aop/spring-aop.xsd
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
            http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
    
    
    
        <context:property-placeholder location="redis.properties"/>
        
        <bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">
            
            <property name="maxIdle" value="${redis.maxIdle}" />
            
            <property name="maxTotal" value="${redis.maxTotal}" />
            
            <property name="maxWaitMillis" value="${redis.maxWaitMillis}"/>
            
            <property name="blockWhenExhausted" value="${redis.blockWhenExhausted}"/>
            
            <property name="testOnBorrow" value="${redis.testOnBorrow}"/>
        </bean>
        
        <bean  id="jedisConnectionFactory" class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory">
            
            <property name="hostName" value="127.0.0.1"/>
            
            <property name="port" value="6379"/>
            
            <property name="poolConfig" ref="poolConfig"/>
        </bean>
    
        
        <bean class="org.springframework.data.redis.core.RedisTemplate">
            <property name="connectionFactory" ref="jedisConnectionFactory"/>
        </bean>
    </beans>

4：使用redis缓存

package com.yc.controller;
    
    import com.yc.po.Hotel;
    import com.yc.zip.impl.HotelBizImpl;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.data.redis.core.RedisTemplate;
    import org.springframework.data.redis.core.ValueOperations;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.ResponseBody;
    
    import java.util.List;
    
    /**
     * @author Administrator
     */
    @Controller
    @RequestMapping("/hotel")
    public class HotelController {
    
        @Autowired
        private HotelBizImpl biz;
        /**
         * 自动装配RedisTemplate
         */
        @Autowired
        RedisTemplate redisTemplate = new RedisTemplate();
    
    
        @RequestMapping("/finds")
        @ResponseBody
        //查询前最后6条酒店信息
        public List<Hotel> finds() {
            return biz.finds();
        }
    
        @RequestMapping("/findAll")
        @ResponseBody
        //查看所有酒店信息
        public List<Hotel> findAll() {
            return biz.findAll();
        }
    
    
        @RequestMapping("/findByStar")
        @ResponseBody
        //根据星级查询酒店信息
        public List<Hotel> findByStart(String start) {
            int star = Integer.parseInt(start);
            //获取模板中的缓存数据
            ValueOperations<Integer,List> string = redisTemplate.opsForValue();
            //判断缓存中是否有对应的键，若果有就从redis中查询，没有就从数据库中查询，然后设置到redis中
            if (redisTemplate.hasKey(star)){
                System.out.println("从redis中查询");
                return string.get(star);
            }else {
                System.out.println("从数据库中查询");
                string.set(star,biz.findByStart(start));
                return biz.findByStart(start);
            }
        }
    
    }