redis的使用简记

Jedis的使用

思路：创建一个redis操作的接口。分别创建两个实现类对应redis的单机版和集群版。当使用单机版redis时，配置单机版的实现类，当使用集群版时，配置集群版实现类

单机版实现类：

注：jedis常用方法API可参见 https://blog.csdn.net/zhangguanghui002/article/details/78770071

/**
 * redis客户端单机版实现类
*/

public class JedisClientSingle implements JedisClient{
    
    @Autowired
    private JedisPool jedisPool;

    @Override
    public String set(String key, String value) {
        Jedis jedis = jedisPool.getResource();
        String result = jedis.set(key, value);
        jedis.close();
        return result;
    }

    @Override
    public String get(String key) {
        Jedis jedis = jedisPool.getResource();
        String result = jedis.get(key);
        jedis.close();
        return result;
    }

    @Override
    public Long hset(String key, String item, String value) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.hset(key, item, value);
        jedis.close();
        return result;
    }

    @Override
    public String hget(String key, String item) {
        Jedis jedis = jedisPool.getResource();
        String result = jedis.hget(key, item);
        jedis.close();
        return result;
    }

    @Override
    public Long incr(String key) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.incr(key);
        jedis.close();
        return result;
    }

    @Override
    public Long decr(String key) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.decr(key);
        jedis.close();
        return result;
    }

    @Override
    public Long expire(String key, int second) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.expire(key, second);
        jedis.close();
        return result;
    }
    @Override
    public Long ttl(String key) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.ttl(key);
        jedis.close();
        return result;
    }

}

集群版实现类：

/**
 * redis客户端集群版实现类
 
 */
public class JedisClientCluster implements JedisClient {
    
    @Autowired
    private JedisCluster jedisCluster;

    @Override
    public String set(String key, String value) {
        return jedisCluster.set(key, value);
    }

    @Override
    public String get(String key) {
        return jedisCluster.get(key);
    }

    @Override
    public Long hset(String key, String item, String value) {
        return jedisCluster.hset(key, item, value);
    }

    @Override
    public String hget(String key, String item) {
        return jedisCluster.hget(key, item);
    }

    @Override
    public Long incr(String key) {
        return jedisCluster.incr(key);
    }

    @Override
    public Long decr(String key) {
        return jedisCluster.decr(key);
    }

    @Override
    public Long expire(String key, int second) {
        return jedisCluster.expire(key, second);
    }

    @Override
    public Long ttl(String key) {
        return jedisCluster.ttl(key);
    }

}

Spring的配置：

<!-- 配置redis客户端单机版 -->
    <bean id="jedisPool" class="redis.clients.jedis.JedisPool">
        <constructor-arg name="host" value="192.168.25.153"></constructor-arg>
        <constructor-arg name="port" value="6379"></constructor-arg>
    </bean>
    <!-- 配置redis客户端实现类 -->
    <bean id="jedisClientSingle" class=" "/>
    
    <!-- 配置redis客户端集群版 -->
    <!-- <bean id="jedisCluster" class="redis.clients.jedis.JedisCluster">
        <constructor-arg>
            <set>
                <bean class="redis.clients.jedis.HostAndPort">
                    <constructor-arg name="host" value="192.168.25.153"/>
                    <constructor-arg name="port" value="7001"/>
                </bean>
                <bean class="redis.clients.jedis.HostAndPort">
                    <constructor-arg name="host" value="192.168.25.153"/>
                    <constructor-arg name="port" value="7002"/>
                </bean>
                <bean class="redis.clients.jedis.HostAndPort">
                    <constructor-arg name="host" value="192.168.25.153"/>
                    <constructor-arg name="port" value="7003"/>
                </bean>
                <bean class="redis.clients.jedis.HostAndPort">
                    <constructor-arg name="host" value="192.168.25.153"/>
                    <constructor-arg name="port" value="7004"/>
                </bean>
                <bean class="redis.clients.jedis.HostAndPort">
                    <constructor-arg name="host" value="192.168.25.153"/>
                    <constructor-arg name="port" value="7005"/>
                </bean>
                <bean class="redis.clients.jedis.HostAndPort">
                    <constructor-arg name="host" value="192.168.25.153"/>
                    <constructor-arg name="port" value="7006"/>
                </bean>
            </set>
        </constructor-arg>
    </bean>
    <bean id="jedisClientCluster" class=" "/> -->

业务逻辑中添加缓存：

@Override
    public List<TbContent> getContentList(Long cid) {
        //添加缓存
        //查询数据库之前先查询缓存，如果有直接返回
        try {
            //从redis中取缓存数据
            String json = jedisClient.hget(REDIS_CONTENT_KEY, cid+"");
            if (!StringUtils.isBlank(json)) {
                //把json转换成List
                List<TbContent> list = JsonUtils.jsonToList(json, TbContent.class);
                return list;
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        // 根据cid查询内容列表
        TbContentExample example = new TbContentExample();
        Criteria criteria = example.createCriteria();
        criteria.andCategoryIdEqualTo(cid);
        //执行查询
        List<TbContent> list = contentMapper.selectByExampleWithBLOBs(example);
        
        //返回结果之前，向缓存中添加数据
        try {
            //为了规范key可以使用hash
            //定义一个保存内容的key，hash中每个项就是cid
            //value是list，需要把list转换成json数据。
            jedisClient.hset(REDIS_CONTENT_KEY, cid+"", JsonUtils.objectToJson(list));
        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }

测试：

@Test
    public void testJedisClientSpring() throws Exception {
        //创建一个spring容器
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:spring/applicationContext-*.xml");
        //从容器中获得JedisClient对象
        JedisClient jedisClient = applicationContext.getBean(JedisClient.class);
        //jedisClient操作redis
        jedisClient.set("cliet1", "1000");
        String string = jedisClient.get("cliet1");
        System.out.println(string);
    }