Redis系列一：Redis介绍

之前看了《Redis入门指南》第二版，在有道上零零散散的记录些内容，现在觉得还是有必要整理完善下，方便自己查看哈😄

redis的安装，书籍以及网络资料一大堆，我就不在此赘述了。

一、什么是Redis

Redis 是一个开源（BSD许可）的，是一种基于键值对（key-value）内存中的数据结构存储系统，它可以用作数据库、缓存和消息中间件。 它支持多种类型的数据结构，如 字符串（strings）， 散列（hashes）， 列表（lists）， 集合（sets）， 有序集合（sorted sets） 与范围查询， bitmaps， hyperl 和地理空间（geospatial） 索引半径查询。 Redis 内置了 复制（replication），LUA脚本（Lua scripting）， LRU驱动事件（LRU eviction），事务（transactions） 和不同级别的 磁盘持久化（persistence）， 并通过 Redis哨兵（Sentinel）和自动 分区（Cluster）提供高可用性（high availability）。

二、Redis特性

1、速度快，数据放在内存中，由C语言编写，官方提供的数据是可以达到10w+/s的qps，与机器性能也有关。这个数据不比采用单进程多线程的同样基于内存的kv数据库Memcached差

1）完全基于内存；

2）数据结构简单，对数据操作也简单；

3）采用单线程架构（使用多路I/O复用模型），预防多线程可能产生的竞争问题。

 

2、键值对的数据结构

3、丰富的功能：数据库、缓存、消息中间件。。

4、简单稳定：单线程

5、持久化： 发生断电或机器故障，数据可能会丢失，持久化到硬盘

6、主从复制：实现多个相同数据的redis副本

7、高可用和分布式：哨兵机制实现高可用，保证redis节点故障发现和自动转移

8、客户端多语言：java php python c c++ nodejs等

三、Redis应用场景

1、缓存：合理使用缓存，加快访问数据的速度，降低后端数据源的压力

2、排行版：按照热度排名，按照发布时间排名，主要用到列表和有序集合

3、计数器应用：视频网站播放数，网站浏览数，使用redis计数

4、社交网络：踩、赞、粉丝、下拉刷新

5、消息队列：发布和订阅

四、Redis使用（主要介绍Java版）

Jedis是Redis官方推荐的Java连接开发工具，要在Java开发中使用好Redis中间件，必须熟悉Jedis。

Jedis的基本使用非常简单，只需要创建Jedis对象的时候指定host，port, password即可。当然，Jedis对象又很多构造方法，都大同小异，只是对应和Redis连接的socket的参数不一样而已。简单使用如下图所示：

 

引入Jedis依赖包

<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>2.9.0</version>
    <type>jar</type>
    <scope>compile</scope>
</dependency>

 

Jedis连接redis三种模式：

• 单机模式
• 分片模式
• 集群模式（since3.0）

 

 

 1、使用单机模式连接

创建Jedis对象，set方法存储key-value值，get方法获取key对应的值，主要用于单个redis。

下图为Jedis类结构的关系图：

每一个接口都代表了一类Redis命令，例如JedisCommands中包含了SET GET等命令，MultiKeyCommands中包含了针对多个Key的MSET MGET等命令。

1）redis java String示例

Jedis jedis = new Jedis("192.168.56.180", 6379);
//jedis.auth("123456"); // 若在redis配置中配置了权限密码，这里需要设置
jedis.set("Jedis", "Hello Work!");
System.out.println(jedis.get("Jedis")); 
jedis.close();

 

2）redis java List 示例

 /***
     * 列表
     */
    @Test
    public void testList() {
        jedis.flushDB();
        System.out.println("===========添加一个list===========");
        jedis.lpush("collections", "ArrayList", "Vector", "Stack", "HashMap", "WeakHashMap", "LinkedHashMap");
        jedis.lpush("collections", "HashSet");
        jedis.lpush("collections", "TreeSet");
        jedis.lpush("collections", "TreeMap");
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));//-1代表倒数第一个元素，-2代表倒数第二个元素
        System.out.println("collections区间0-3的元素："+jedis.lrange("collections",0,3));
        System.out.println("===============================");
        // 删除列表指定的值 ，第二个参数为删除的个数（有重复时），后add进去的值先被删，类似于出栈
        System.out.println("删除指定元素个数："+jedis.lrem("collections", 2, "HashMap"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("删除下表0-3区间之外的元素："+jedis.ltrim("collections", 0, 3));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("collections列表出栈（左端）："+jedis.lpop("collections"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("collections添加元素，从列表右端，与lpush相对应："+jedis.rpush("collections", "EnumMap"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("collections列表出栈（右端）："+jedis.rpop("collections"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("修改collections指定下标1的内容："+jedis.lset("collections", 1, "LinkedArrayList"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("===============================");
        System.out.println("collections的长度："+jedis.llen("collections"));
        System.out.println("获取collections下标为2的元素："+jedis.lindex("collections", 2));
        System.out.println("===============================");
        jedis.lpush("sortedList", "3","6","2","0","7","4");
        System.out.println("sortedList排序前："+jedis.lrange("sortedList", 0, -1));
        System.out.println(jedis.sort("sortedList"));
        System.out.println("sortedList排序后："+jedis.lrange("sortedList", 0, -1));
    }

 

3) redis java Keys 示例

Jedis jedis = new Jedis("192.168.56.180", 6379);
Set<String> keys = Jedis.keys("*");
Iterator<String> it = keys.iterator();
while(it.hasNext()){
  String key = ite.next();
  System.out.println(key);
}
jedis.close();

 

4）redis java set示例

 /***
     * set集合
     */
    @Test
    public void testSet() {
        jedis.flushDB();
        System.out.println("============向集合中添加元素============");
        System.out.println(jedis.sadd("eleSet", "e1","e2","e4","e3","e0","e8","e7","e5"));
        System.out.println(jedis.sadd("eleSet", "e6"));
        System.out.println(jedis.sadd("eleSet", "e6"));
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("删除一个元素e0："+jedis.srem("eleSet", "e0"));
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("删除两个元素e7和e6："+jedis.srem("eleSet", "e7","e6"));
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("随机的移除集合中的一个元素："+jedis.spop("eleSet"));
        System.out.println("随机的移除集合中的一个元素："+jedis.spop("eleSet"));
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("eleSet中包含元素的个数："+jedis.scard("eleSet"));
        System.out.println("e3是否在eleSet中："+jedis.sismember("eleSet", "e3"));
        System.out.println("e1是否在eleSet中："+jedis.sismember("eleSet", "e1"));
        System.out.println("e1是否在eleSet中："+jedis.sismember("eleSet", "e5"));
        System.out.println("=================================");
        System.out.println(jedis.sadd("eleSet1", "e1","e2","e4","e3","e0","e8","e7","e5"));
        System.out.println(jedis.sadd("eleSet2", "e1","e2","e4","e3","e0","e8"));
        System.out.println("将eleSet1中删除e1并存入eleSet3中："+jedis.smove("eleSet1", "eleSet3", "e1"));
        System.out.println("将eleSet1中删除e2并存入eleSet3中："+jedis.smove("eleSet1", "eleSet3", "e2"));
        System.out.println("eleSet1中的元素："+jedis.smembers("eleSet1"));
        System.out.println("eleSet3中的元素："+jedis.smembers("eleSet3"));
        System.out.println("============集合运算=================");
        System.out.println("eleSet1中的元素："+jedis.smembers("eleSet1"));
        System.out.println("eleSet2中的元素："+jedis.smembers("eleSet2"));
        System.out.println("eleSet1和eleSet2的交集:"+jedis.sinter("eleSet1","eleSet2"));
        System.out.println("eleSet1和eleSet2的并集:"+jedis.sunion("eleSet1","eleSet2"));
        System.out.println("eleSet1和eleSet2的差集:"+jedis.sdiff("eleSet1","eleSet2"));//eleSet1中有，eleSet2中没有
    }

 

5）redis java hash示例

/***
     * 散列
     */
    @Test
    public void testHash() {
        jedis.flushDB();
        Map<String,String> map = new HashMap<String,String>();
        map.put("key1","value1");
        map.put("key2","value2");
        map.put("key3","value3");
        map.put("key4","value4");
        jedis.hmset("hash",map);
        jedis.hset("hash", "key5", "value5");
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));//return Map<String,String>
        System.out.println("散列hash的所有键为："+jedis.hkeys("hash"));//return Set<String>
        System.out.println("散列hash的所有值为："+jedis.hvals("hash"));//return List<String>
        System.out.println("将key6保存的值加上一个整数，如果key6不存在则添加key6："+jedis.hincrBy("hash", "key6", 6));
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));
        System.out.println("将key6保存的值加上一个整数，如果key6不存在则添加key6："+jedis.hincrBy("hash", "key6", 3));
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));
        System.out.println("删除一个或者多个键值对："+jedis.hdel("hash", "key2"));
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));
        System.out.println("散列hash中键值对的个数："+jedis.hlen("hash"));
        System.out.println("判断hash中是否存在key2："+jedis.hexists("hash","key2"));
        System.out.println("判断hash中是否存在key3："+jedis.hexists("hash","key3"));
        System.out.println("获取hash中的值："+jedis.hmget("hash","key3"));
        System.out.println("获取hash中的值："+jedis.hmget("hash","key3","key4"));
    }

 

6）redis java zset示例

 /**
     * 有序集合
     */
    @Test
    public void testSortedSet() {
        jedis.flushDB();
        Map<String,Double> map = new HashMap<String,Double>();
        map.put("key2",1.2);
        map.put("key3",4.0);
        map.put("key4",5.0);
        map.put("key5",0.2);
        System.out.println(jedis.zadd("zset", 3,"key1"));
        System.out.println(jedis.zadd("zset",map));
        System.out.println("zset中的所有元素："+jedis.zrange("zset", 0, -1));
        System.out.println("zset中的所有元素："+jedis.zrangeWithScores("zset", 0, -1));
        System.out.println("zset中的所有元素："+jedis.zrangeByScore("zset", 0,100));
        System.out.println("zset中的所有元素："+jedis.zrangeByScoreWithScores("zset", 0,100));
        System.out.println("zset中key2的分值："+jedis.zscore("zset", "key2"));
        System.out.println("zset中key2的排名："+jedis.zrank("zset", "key2"));
        System.out.println("删除zset中的元素key3："+jedis.zrem("zset", "key3"));
        System.out.println("zset中的所有元素："+jedis.zrange("zset", 0, -1));
        System.out.println("zset中元素的个数："+jedis.zcard("zset"));
        System.out.println("zset中分值在1-4之间的元素的个数："+jedis.zcount("zset", 1, 4));
        System.out.println("key2的分值加上5："+jedis.zincrby("zset", 5, "key2"));
        System.out.println("key3的分值加上4："+jedis.zincrby("zset", 4, "key3"));
        System.out.println("zset中的所有元素："+jedis.zrange("zset", 0, -1));
    }

 

7）redis java sort 示例

/**
     * 排序
     */
    @Test
    public void testSort()
    {
        jedis.flushDB();
        jedis.lpush("collections", "ArrayList", "Vector", "Stack", "HashMap", "WeakHashMap", "LinkedHashMap");
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        SortingParams sortingParameters = new SortingParams();
        System.out.println(jedis.sort("collections",sortingParameters.alpha()));
        System.out.println("===============================");
        jedis.lpush("sortedList", "3","6","2","0","7","4");
        System.out.println("sortedList排序前："+jedis.lrange("sortedList", 0, -1));
        System.out.println("升序："+jedis.sort("sortedList", sortingParameters.asc()));
        System.out.println("升序："+jedis.sort("sortedList", sortingParameters.desc()));
        System.out.println("===============================");
        jedis.lpush("userlist", "33");
        jedis.lpush("userlist", "22");
        jedis.lpush("userlist", "55");
        jedis.lpush("userlist", "11");
        jedis.hset("user:66", "name", "66");
        jedis.hset("user:55", "name", "55");
        jedis.hset("user:33", "name", "33");
        jedis.hset("user:22", "name", "79");
        jedis.hset("user:11", "name", "24");
        jedis.hset("user:11", "add", "beijing");
        jedis.hset("user:22", "add", "shanghai");
        jedis.hset("user:33", "add", "guangzhou");
        jedis.hset("user:55", "add", "chongqing");
        jedis.hset("user:66", "add", "xi'an");
        sortingParameters = new SortingParams();
        sortingParameters.get("user:*->name");
        sortingParameters.get("user:*->add");
        System.out.println(jedis.sort("userlist",sortingParameters));
    }
}

 

8）部分其他命令

Jedis jedis = new Jedis("192.168.56.180", 6379);
System.out.println("清空数据："+jedis.flushDB());
System.out.println("判断某个键是否存在："+jedis.exists("username"));
System.out.println("新增<'username','wukong'>的键值对："+jedis.set("username", "wukong"));
System.out.println("是否存在:"+jedis.exists("name"));
System.out.println("新增<'password','password'>的键值对："+jedis.set("password", "password"));
Set<String> keys = jedis.keys("*");
System.out.println("系统中所有的键如下："+keys);
System.out.println("删除键password:"+jedis.del("password"));
System.out.println("判断键password是否存在："+jedis.exists("password"));
System.out.println("设置键username的过期时间为5s:"+jedis.expire("username", 5));
TimeUnit.SECONDS.sleep(2);
System.out.println("查看键username的剩余生存时间："+jedis.ttl("username"));
System.out.println("移除键username的生存时间："+jedis.persist("username"));
System.out.println("查看键username的剩余生存时间："+jedis.ttl("username"));
System.out.println("查看键username所存储的值的类型："+jedis.type("username"));
System.out.println(jedis.set("key3", "value3"));
System.out.println("在key3后面加入值："+jedis.append("key3", "End"));
System.out.println("key3的值："+jedis.get("key3"));
System.out.println("增加多个键值对："+jedis.mset("key01","value01","key02","value02","key03","value03"));
System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03"));
System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03","key04"));
System.out.println("删除多个键值对："+jedis.del(new String[]{"key01","key02"}));
System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03"));

jedis.flushDB();
System.out.println("===========新增键值对防止覆盖原先值==============");
System.out.println(jedis.setnx("key1", "value1"));
System.out.println(jedis.setnx("key2", "value2"));
System.out.println(jedis.setnx("key2", "value2-new"));
System.out.println(jedis.get("key1"));
System.out.println(jedis.get("key2"));

System.out.println("===========新增键值对并设置有效时间=============");
System.out.println(jedis.setex("key3", 2, "value3"));
System.out.println(jedis.get("key3"));
TimeUnit.SECONDS.sleep(3);
System.out.println(jedis.get("key3"));

System.out.println("===========获取原值，更新为新值==========");//GETSET is an atomic set this value and return the old value command.
System.out.println(jedis.getSet("key2", "key2GetSet"));
System.out.println(jedis.get("key2"));

System.out.println("获得key2的值的字串："+jedis.getrange("key2", 2, 4));

//整数、浮点数
jedis.flushDB();
jedis.set("key1", "1");
jedis.set("key2", "2");
jedis.set("key3", "2.3");
System.out.println("key1的值："+jedis.get("key1"));
System.out.println("key2的值："+jedis.get("key2"));
System.out.println("key1的值加1："+jedis.incr("key1"));
System.out.println("获取key1的值："+jedis.get("key1"));
System.out.println("key2的值减1："+jedis.decr("key2"));
System.out.println("获取key2的值："+jedis.get("key2"));
System.out.println("将key1的值加上整数5："+jedis.incrBy("key1", 5));
System.out.println("获取key1的值："+jedis.get("key1"));
System.out.println("将key2的值减去整数5："+jedis.decrBy("key2", 5));
System.out.println("获取key2的值："+jedis.get("key2"));

 

 

2、使用分片模式连接

GenericObjectPoolConfig config=new GenericObjectPoolConfig();
config.setMaxIdle(32); 
config.setMinIdle(12);
config.setTestOnBorrow(true); 
config.setTestOnReturn(rtrue);
config.setTestWhileIdle(true);
List<JedisShardInfo> shards = new ArrayList<JedisShardInfo>(); 
for (int i = 0; i < shareds.size(); i++) {
     shards.add(new JedisShardInfo("192.168.56.180", 6379, 200)); 
}
// 构造池 
ShardedJedisPool shardedJedisPool= new ShardedJedisPool(config, shards);
ShardedJedis jedis=shardedJedisPool.getResource();
jedis.set("a","b");
jedis.hmset(key, hash,value);
jedis.close();
       

 以下是使用JedisPool的方式：

public class RedisUtils {
static {

        String configurationFileName = "xxx.properties";
        Configuration conf = Configuration.getConfiguration(configurationFileName);
        if (conf == null) {
            System.out.println("reading " + configurationFileName + " is failed.");
            System.exit(-1);
        }
        String[] ADDRs = conf.getString("redisIP", "192.168.56.180").split(",");
        String[] PORTs = conf.getString("redisPort", "6379").split(",");

        if (ADDRs.length == 0 || PORTs.length == 0) {
            System.out.println("definition redisIP is not found in " + configurationFileName);
            System.exit(-1);
        }
        JedisPoolConfig config = new JedisPoolConfig();
        config.setMaxIdle(MAX_IDLE);
        config.setTestOnBorrow(TEST_ON_BORROW);
        jedisPool = new JedisPool(config, ADDRs[0], PORT, TIMEOUT);
    }

    public synchronized static Jedis getJedis() {
        if (jedisPool != null) {
            //获取资源
            Jedis resource = jedisPool.getResource();
            return resource;
        } else {
            return null;
        }
    }

    public static void returnBrokenResource(Jedis jedis) {
        if (jedis != null) {
            //释放资源
            jedisPool.returnBrokenResource(jedis);

        }
    }

    public static void returnResource(Jedis jedis) {
        if (jedis != null) {
            //释放资源
            jedisPool.returnResource(jedis);
        }
    }
}

 

3、集群模式JedisCluster

Jediscluster类图和jedis类图大致一样，不过jedisCluster有一些命令是不可用的。比如BinaryJedisCluster类被作废的命令。主要是用在集群中。

 

 

示例：

/**
 * 集群环境下Jedis操作
 */
public class Cluster {
    private static JedisCluster jedis;
    static {
        // 添加集群的服务节点Set集合
        Set<HostAndPort> hostAndPortsSet = new HashSet<HostAndPort>();
        // 添加节点
        hostAndPortsSet.add(new HostAndPort("192.168.56.180", 7777));
        hostAndPortsSet.add(new HostAndPort("192.168.56.180", 8888));
        hostAndPortsSet.add(new HostAndPort("192.168.56.181", 7777));
        hostAndPortsSet.add(new HostAndPort("192.168.56.181", 8888));
        hostAndPortsSet.add(new HostAndPort("192.168.56.182", 7777));
        hostAndPortsSet.add(new HostAndPort("192.168.56.182", 8888));

        // Jedis连接池配置
        JedisPoolConfig jedisPoolConfig = new JedisPoolConfig();
        // 最大空闲连接数, 默认8个
        jedisPoolConfig.setMaxIdle(100);
        // 最大连接数, 默认8个
        jedisPoolConfig.setMaxTotal(500);
        //最小空闲连接数, 默认0
        jedisPoolConfig.setMinIdle(0);
        // 获取连接时的最大等待毫秒数(如果设置为阻塞时BlockWhenExhausted),如果超时就抛异常, 小于零:阻塞不确定的时间,  默认-1
        jedisPoolConfig.setMaxWaitMillis(2000); // 设置2秒
        //对拿到的connection进行validateObject校验
        jedisPoolConfig.setTestOnBorrow(true);
        jedis = new JedisCluster(hostAndPortsSet, jedisPoolConfig);
    }

    /**
     * 测试key:value数据
     * 集群中flushDB、keys废弃
     */
    @Test
    public void testKey() throws InterruptedException {
        //System.out.println("清空数据："+jedis.flushDB());
        System.out.println("判断某个键是否存在："+jedis.exists("username"));
        System.out.println("新增<'username','wukong'>的键值对："+jedis.set("username", "xiaohai"));
        System.out.println("是否存在:"+jedis.exists("username"));
        System.out.println("新增<'password','password'>的键值对："+jedis.set("password", "123456"));
        //Set<String> keys = jedis.keys("*");
        // System.out.println("系统中所有的键如下："+keys);
        System.out.println("删除键password:"+jedis.del("password"));
        System.out.println("判断键password是否存在："+jedis.exists("password"));
        System.out.println("设置键username的过期时间为10s:"+jedis.expire("username", 10));
        TimeUnit.SECONDS.sleep(2); // 线程睡眠2秒System.out.println("查看键username的剩余生存时间："+jedis.ttl("username"));
        System.out.println("查看键username的剩余生存时间："+jedis.ttl("username"));
        System.out.println("移除键username的生存时间："+jedis.persist("username"));
        System.out.println("查看键username的剩余生存时间："+jedis.ttl("username"));
        System.out.println("查看键username所存储的值的类型："+jedis.type("username"));
    }

    /***
     * 字符串操作
     * memcached和redis同样有append的操作，但是memcached有prepend的操作，redis中并没有。
     * 集群中flushDB、keys、del(多个值)、mset(多个值)废弃
     * @throws InterruptedException
     */
    @Test
    public void testString() throws InterruptedException {
        //jedis.flushDB();
        System.out.println("===========增加数据===========");
        System.out.println(jedis.set("key1","value1"));
        System.out.println(jedis.set("key2","value2"));
        System.out.println(jedis.set("key3", "value3"));
        System.out.println("删除键key2:"+jedis.del("key2"));
        System.out.println("获取键key2:"+jedis.get("key2"));
        System.out.println("修改key1:"+jedis.set("key1", "value1Changed"));
        System.out.println("获取key1的值："+jedis.get("key1"));
        System.out.println("在key3后面加入值："+jedis.append("key3", "End"));
        System.out.println("key3的值："+jedis.get("key3"));
        //命令的时候才会去连接连接，集群中连接是对一个节点连接，不能判断多个key经过crc16算法所对应的槽在一个节点上，不支持多key获取、删除
        //System.out.println("增加多个键值对："+jedis.mset("key01","value01","key02","value02"));
        //System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03"));
        //System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03","key04"));
        //System.out.println("删除多个键值对："+jedis.del(new String[]{"key01","key02"}));
        //System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03"));

        //jedis.flushDB();
        System.out.println("===========新增键值对防止覆盖原先值==============");
        System.out.println(jedis.setnx("key1", "value1"));
        System.out.println(jedis.setnx("key2", "value2"));
        System.out.println(jedis.setnx("key2", "value2-new"));
        System.out.println(jedis.get("key1"));
        System.out.println(jedis.get("key2"));

        System.out.println("===========新增键值对并设置有效时间=============");
        System.out.println(jedis.setex("key3", 2, "value3"));
        System.out.println(jedis.get("key3"));
        TimeUnit.SECONDS.sleep(3);
        System.out.println(jedis.get("key3"));

        System.out.println("===========获取原值，更新为新值==========");//GETSET is an atomic set this value and return the old value command.
        System.out.println(jedis.getSet("key2", "key2GetSet"));
        System.out.println(jedis.get("key2"));
        System.out.println("获得key2的值的字串："+jedis.getrange("key2", 2, 4)); // 相当截取字符串的第二个位置-第四个位置的字符串
    }

    /***
     * 整数和浮点数
     */
    @Test
    public void testNumber() {
        jedis.set("key1", "1");
        jedis.set("key2", "2");
        jedis.set("key3", "2.3");
        System.out.println("key1的值："+jedis.get("key1"));
        System.out.println("key2的值："+jedis.get("key2"));
        System.out.println("key1的值加1："+jedis.incr("key1"));
        System.out.println("获取key1的值："+jedis.get("key1"));
        System.out.println("key2的值减1："+jedis.decr("key2"));
        System.out.println("获取key2的值："+jedis.get("key2"));
        System.out.println("将key1的值加上整数5："+jedis.incrBy("key1", 5));
        System.out.println("获取key1的值："+jedis.get("key1"));
        System.out.println("将key2的值减去整数5："+jedis.decrBy("key2", 5));
        System.out.println("获取key2的值："+jedis.get("key2"));
        System.out.println("key3的值："+jedis.get("key3"));
        // 这里会报错，因为key3不是整数不能做计算:redis.clients.jedis.exceptions.JedisDataException: ERR value is not an integer or out of range
        // System.out.println("key2的值减1："+jedis.decr("key3"));
    }

    /***
     * 列表
     */
    @Test
    public void testList() {
        System.out.println("===========添加一个list===========");
        jedis.lpush("collections", "ArrayList", "Vector", "Stack", "HashMap", "WeakHashMap", "LinkedHashMap");
        jedis.lpush("collections", "HashSet"); // 叠加
        jedis.lpush("collections", "TreeSet"); // 叠加
        jedis.lpush("collections", "TreeMap"); // 叠加
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));//-1代表倒数第一个元素，-2代表倒数第二个元素
        System.out.println("collections区间0-3的元素："+jedis.lrange("collections",0,3)); // 前面4个值
        System.out.println("===============================");
        // 删除列表指定的值 ，第二个参数为删除的个数（有重复时），后add进去的值先被删，类似于出栈
        System.out.println("删除指定元素个数："+jedis.lrem("collections", 2, "HashMap"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("删除下表0-3区间之外的元素："+jedis.ltrim("collections", 0, 3));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("collections列表出栈（左端）："+jedis.lpop("collections"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("collections添加元素，从列表右端，与lpush相对应："+jedis.rpush("collections", "EnumMap"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("collections列表出栈（右端）："+jedis.rpop("collections"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("修改collections指定下标1的内容："+jedis.lset("collections", 1, "LinkedArrayList"));
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        System.out.println("===============================");
        System.out.println("collections的长度："+jedis.llen("collections"));
        System.out.println("获取collections下标为2的元素："+jedis.lindex("collections", 2));
        System.out.println("===============================");
        jedis.lpush("sortedList", "3","6","2","0","7","4");
        System.out.println("sortedList排序前："+jedis.lrange("sortedList", 0, -1));
        System.out.println(jedis.sort("sortedList"));
        System.out.println("sortedList排序后："+jedis.lrange("sortedList", 0, -1));
    }

    /***
     * set集合
     */
    @Test
    public void testSet() {
        System.out.println("============向集合中添加元素============");
        System.out.println(jedis.sadd("eleSet", "e1","e2","e4","e3","e0","e8","e7","e5"));
        System.out.println(jedis.sadd("eleSet", "e6"));
        System.out.println(jedis.sadd("eleSet", "e6")); // 返回0，集合中已经存在
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("删除一个元素e0："+jedis.srem("eleSet", "e0"));
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("删除两个元素e7和e6："+jedis.srem("eleSet", "e7","e6"));
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("随机的移除集合中的一个元素："+jedis.spop("eleSet"));
        System.out.println("随机的移除集合中的一个元素："+jedis.spop("eleSet"));
        System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
        System.out.println("eleSet中包含元素的个数："+jedis.scard("eleSet"));
        System.out.println("e3是否在eleSet中："+jedis.sismember("eleSet", "e3"));
        System.out.println("e1是否在eleSet中："+jedis.sismember("eleSet", "e1"));
        System.out.println("e5是否在eleSet中："+jedis.sismember("eleSet", "e5"));

        // 集群下并存会报错：redis.clients.jedis.exceptions.JedisClusterException: No way to dispatch this command to Redis Cluster because keys have different slots.
        // Redis集群，从key1集合与key2集合并存、交集、差集，两个键经过crc16算法可能有不同的槽。
        /*System.out.println("=================================");
        System.out.println(jedis.sadd("eleSet1", "e1","e2","e4","e3","e0","e8","e7","e5"));
        System.out.println(jedis.sadd("eleSet2", "e1","e2","e4","e3","e0","e8"));
        System.out.println("将eleSet1中删除e1并存入eleSet3中："+jedis.smove("eleSet1", "eleSet3", "e1"));
        System.out.println("将eleSet1中删除e2并存入eleSet3中："+jedis.smove("eleSet1", "eleSet3", "e2"));
        System.out.println("eleSet1中的元素："+jedis.smembers("eleSet1"));
        System.out.println("eleSet3中的元素："+jedis.smembers("eleSet3"));*/

        /*System.out.println("============集合运算=================");
        System.out.println("eleSet1中的元素："+jedis.smembers("eleSet1"));
        System.out.println("eleSet2中的元素："+jedis.smembers("eleSet2"));
        System.out.println("eleSet1和eleSet2的交集:"+jedis.sinter("eleSet1","eleSet2"));
        System.out.println("eleSet1和eleSet2的并集:"+jedis.sunion("eleSet1","eleSet2"));
        System.out.println("eleSet1和eleSet2的差集:"+jedis.sdiff("eleSet1","eleSet2"));*/
        jedis.del("eleSet");
        jedis.del("eleSet1");
        jedis.del("eleSet2");
        jedis.del("eleSet3");
    }

    /***
     * 散列
     */
    @Test
    public void testHash() {
        Map<String,String> map = new HashMap<String,String>();
        map.put("key1","value1");
        map.put("key2","value2");
        map.put("key3","value3");
        map.put("key4","value4");
        jedis.hmset("hash",map);
        jedis.hset("hash", "key5", "value5");
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));//return Map<String,String>
        System.out.println("散列hash的所有键为："+jedis.hkeys("hash"));//return Set<String>
        System.out.println("散列hash的所有值为："+jedis.hvals("hash"));//return List<String>
        System.out.println("将key6保存的值加上一个整数，如果key6不存在则添加key6："+jedis.hincrBy("hash", "key6", 6));
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));
        System.out.println("将key6保存的值加上一个整数，如果key6不存在则添加key6："+jedis.hincrBy("hash", "key6", 3));
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));
        System.out.println("删除一个或者多个键值对："+jedis.hdel("hash", "key2"));
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));
        System.out.println("散列hash中键值对的个数："+jedis.hlen("hash"));
        System.out.println("判断hash中是否存在key2："+jedis.hexists("hash","key2"));
        System.out.println("判断hash中是否存在key3："+jedis.hexists("hash","key3"));
        System.out.println("获取hash中的值："+jedis.hmget("hash","key3"));
        System.out.println("获取hash中的值："+jedis.hmget("hash","key3","key4"));
    }

    /**
     * 有序集合
     */
    @Test
    public void testSortedSet() {
        Map<String,Double> map = new HashMap<String,Double>();
        map.put("key2",1.2);
        map.put("key3",4.0);
        map.put("key4",5.0);
        map.put("key5",0.2);
        // 将一个或多个 member 元素及其 score 值加入到有序集 key 当中，如果某个 member 已经是有序集的成员，那么更新这个 member 的 score 值
        // score 值可以是整数值或双精度浮点数
        System.out.println(jedis.zadd("zset", 3,"key1"));
        System.out.println(jedis.zadd("zset",map));
        System.out.println("zset中的所有元素："+jedis.zrange("zset", 0, -1));
        System.out.println("zset中的所有元素："+jedis.zrangeWithScores("zset", 0, -1));
        System.out.println("zset中的所有元素："+jedis.zrangeByScore("zset", 0,100));
        System.out.println("zset中的所有元素："+jedis.zrangeByScoreWithScores("zset", 0,100));
        System.out.println("zset中key2的分值："+jedis.zscore("zset", "key2"));
        System.out.println("zset中key2的排名："+jedis.zrank("zset", "key2"));
        System.out.println("删除zset中的元素key3："+jedis.zrem("zset", "key3"));
        System.out.println("zset中的所有元素："+jedis.zrange("zset", 0, -1));
        System.out.println("zset中元素的个数："+jedis.zcard("zset"));
        System.out.println("zset中分值在1-4之间的元素的个数："+jedis.zcount("zset", 1, 4));
        System.out.println("key2的分值加上5："+jedis.zincrby("zset", 5, "key2"));
        System.out.println("key3的分值加上4："+jedis.zincrby("zset", 4, "key3"));
        System.out.println("zset中的所有元素："+jedis.zrange("zset", 0, -1));
    }

    /**
     * 排序
     */
    @Test
    public void testSort() {
        jedis.lpush("collections", "ArrayList", "Vector", "Stack", "HashMap", "WeakHashMap", "LinkedHashMap");
        System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
        SortingParams sortingParameters = new SortingParams();
        // 当数据集中保存的是字符串值时，你可以用 ALPHA,默认是升序
        System.out.println("alpha排序方式：" + jedis.sort("collections",sortingParameters.alpha()));
        System.out.println("===============================");
        jedis.lpush("sortedList", "3","6","2","0","7","4");
        System.out.println("sortedList排序前："+jedis.lrange("sortedList", 0, -1));
        System.out.println("升序："+jedis.sort("sortedList", sortingParameters.asc()));
        System.out.println("降序："+jedis.sort("sortedList", sortingParameters.desc()));
        System.out.println("===============================");
        // 集群下不支持分割表排序
        /*jedis.lpush("userlist", "33");
        jedis.lpush("userlist", "22");
        jedis.lpush("userlist", "55");
        jedis.lpush("userlist", "11");
        jedis.hset("user:66", "name", "66");
        jedis.hset("user:55", "name", "55");
        jedis.hset("user:33", "name", "33");
        jedis.hset("user:22", "name", "79");
        jedis.hset("user:11", "name", "24");
        jedis.hset("user:11", "add", "beijing");
        jedis.hset("user:22", "add", "shanghai");
        jedis.hset("user:33", "add", "guangzhou");
        jedis.hset("user:55", "add", "chongqing");
        jedis.hset("user:66", "add", "xi'an");
        sortingParameters = new SortingParams();
        // 符号 "->" 用于分割哈希表的键名(key name)和索引域(hash field)，格式为 "key->field"
        sortingParameters.get("user:*->name");
        sortingParameters.get("user:*->add");
        System.out.println(jedis.sort("userlist",sortingParameters));*/
    }

 

使用时要点：

1、版本号

版本号第二位为奇数，为非稳定版本（2.7，2.9，3.1），是开发版本；第二位为偶数，为稳定版本（2.6，2.8，3.0）。

2、reids命令

redis原生命令不区分大小写，所有的redis命令都是原子操作。