redis—Spring中redis缓存的简单使用

这里使用的是 Spring-4.3 , redis-2.8 的版本

 

1、添加maven依赖

<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>2.8.0</version>
</dependency>

2、编写自己的redisAPI

package com.del.tools;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool; 

/**
 * 用于缓存的数据访问对象
 * @author Domi
 */
public class RedisAPI { 

        //引入jedis连接池对象
        public JedisPool jedisPool;
        public JedisPool getJedisPool() {
               return jedisPool;
        }
        public void setJedisPool(JedisPool jedisPool) {
               this.jedisPool = jedisPool;
        }

       /**
        * 缓存的设置
        */
        public boolean set(String key,String value){
               Jedis jedis = null;
               try {
                       jedis = jedisPool.getResource();
                       jedis.set(key,value);
                       return true;
               } catch (Exception e) {
                       // TODO: handle exceptionr
                       e.printStackTrace();
               }finally{
                       returnResource(jedisPool, jedis);
               }
               return false;
        }      

        /**
         * 判断缓存中是否存在某个key值
         */
        public boolean exist(String key){
               Jedis jedis =null;
                try {
                       jedis = jedisPool.getResource();
                       return jedis.exists(key);
               } catch (Exception e) {
                       // TODO: handle exception
               }finally{
                       returnResource(jedisPool, jedis);
                       System.out.println("关闭成功===》");
               }
               return false;
        }

        /**
         * 获得缓存中的key
         */
        public String get(String key){
               String value = null;
               Jedis jedis =null;
               try {
                       jedis = jedisPool.getResource();
                       value = jedis.get(key);
               } catch (Exception e) {
                       // TODO: handle exception
               }finally{
                       returnResource(jedisPool, jedis);
               }
               return value;
         }

        /**
         * 返还jedisPool
         */
        public static void returnResource(JedisPool jedisPool,Jedis jedis){
               if (jedis!=null) {
                       jedisPool.returnResource(jedis);
               }
        }
}

 

3、用spring管理redis的bean组件

<!-- jedis连接池配置-->
<bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig">
    <property name="maxTotal" value="1000"/> <!-- 控制一个pool可分配多少个jedis实例 -->
    <property name="maxIdle" value="200" />   <!-- 控制一个pool最多有多少个状态为idle(空闲)的jedis实例 -->
    <property name="maxWaitMillis" value="2000" />  <!-- 表示当borrow一个jedis实例时，最大的等待时间，如果超过等待时间，则直接抛出JedisConnectionException -->
    <property name="testOnBorrow" value="true" /> <!-- 在borrow一个jedis实例时，是否提前进行validate操作；如果为true，则得到的jedis实例均是可用的 -->
</bean> 

<!-- 连接jedis服务器 -->
<bean id="jedisPool" class="redis.clients.jedis.JedisPool" destroy-method="destroy">
    <constructor-arg ref="jedisPoolConfig"/>
    <constructor-arg value="127.0.0.1"/>
    <constructor-arg value="6379"/>
</bean>

<!-- 配置redisAPI -->
<bean id="redisAPI" class="com.del.tools.RedisAPI">
     <property name="jedisPool" ref="jedisPool"/>
</bean>

 

4、在业务中使用redisAPI

/*
         *  根据userID查询购物车列表
         *  使用redis缓存
         */
        @RequestMapping(value="/list")
        public ModelAndView doBuyCarList(HttpSession session){              

               ModelAndView madnv = new ModelAndView();
               User user = (User)session.getAttribute("hasLogin");
               if(user!=null){

                       //先判斷redis裡面有沒有值
                       List<BuyCar> buycarlist1 = null;
                       buycarlist1 = buyCarService.findBuyCarList(user.getUserid());
                      String buycarlist = JSON.toJSONString(buycarlist1,true);
                       redisAPI.set("carlist"+user.getUserid(), buycarlist);
                       madnv.addObject("buycarlist", buycarlist1);
                       System.out.println("buycarlist====="+buycarlist1);
                       System.out.println("FROM DB==>");    

                       }else{
                                 String buycarlist = redisAPI.get("carlist"+user.getUserid());
                                 if (buycarlist!=null && !"".equals(buycarlist)) {
                                       buycarlist1 =JSON.parseArray(buycarlist, BuyCar.class);
                                       madnv.addObject("buycarlist", buycarlist1);
                                       System.out.println("buycarlist====="+buycarlist);
                                       System.out.println("FROM REDIS==>");
                                 }else{
                                             System.out.println("error==>");
                               }
                       }
               }
               madnv.setViewName("buycar/shopping.jsp");
               return madnv;
        }