2024.1.11 关于 Jedis 库操作 Redis 基本演示

发布时间:2024年01月12日

?目录

引言

通用命令

SET & GET

EXISTS &?DEL

KEYS

EXPIRE & TTL

TYPE

String 类型命令

?MGET & MSET

GETRANGE & SETRANGE?

APPEND

INCR & DECR

List 类型命令

LPUSH & LRANG?

LPOP & LPOP

BLPOP & BRPOP

LLEN

Set 类型命令

SADD & SMEMBERS

SISMEMBERS

SCARD

SPOP

SINTER

SINTERSTORE

Hash 类型命令?

HSET & HGET

HEXISTS

HDEL

HKEYS & HVALS

HMGET & HMSET

?ZSet 类型命令

ZADD & ZRANGE

ZCARD

ZREM

ZSCORE

ZRANK


引言

  • Jedis 库的本质就是针对 Redis 的各种命令进行了封装
  • 调用某个方法就相当于在 Redis 客户端中敲下了对应的命令
  • 下文将介绍?Redis 命名在代码中的操作,但不会覆盖到所有的命令,只会挑一些比较重要的、代表性的命令

通用命令

SET & GET

public static void test1(Jedis jedis) {
        System.out.println("get 和 set 的使用");
//        先清空数据库,要避免上一组测试的残留数据影响到下一组测试的结果
        jedis.flushAll();

        jedis.set("key","111");
        jedis.set("key2","222");
//        通过创建 SetParams 的对象,给 set 命令设置参数和选项
        SetParams params = new SetParams();
        params.ex(10);
//        此处设置 XX 选项
//        表示只有当 key 存在时才设置,key 不存在时直接返回 nil
        params.xx();
//        注意此时 set 的 key 在上述代码中已经设置过了
        jedis.set("key","333",params);

        SetParams params2 = new SetParams();
        params2.ex(10);
        params2.xx();
//        注意此时 set 的 key4 并未在上述代码中设置过
        jedis.set("key4","444",params2);

        String value = jedis.get("key");
        System.out.println("此处预期 value = 333, 实际 value = " + value);

        String value4 = jedis.get("key4");
        System.out.println("此处预期 value4 = null, 实际 value4 = " + value4);
}

?运行结果:


EXISTS &?DEL

public static void test2(Jedis jedis) {
        System.out.println("exists 和 del 的使用");
        jedis.flushAll();

        jedis.set("key","111");
        jedis.set("key2","222");
        jedis.set("key3","333");
//        判断 key 是否存在
        boolean result = jedis.exists("key");
        System.out.println("此处预期 result = ture, 实际 result = " + result);
//        在此处直接将 key 删除
        long result2 = jedis.del("key");
        System.out.println("此处预期 result2 = 1, 实际 result2 = " + result2);
//        重新判断 key 是否存在
        result = jedis.exists("key");
        System.out.println("此处预期 result = false, 实际 result =  " + result);
//        使用 del 方法删除多个 key (变长参数)
        result2 = jedis.del("key2","key3");
        System.out.println("此处预期 result2 = 2, 实际 result2 = " + result2);
}

运行结果:


KEYS

public static void test3(Jedis jedis) {
        System.out.println("keys 的使用");
        jedis.flushAll();

        jedis.set("key","111");
        jedis.set("key2","222");
        jedis.set("key3","333");
        jedis.set("key4","444");
//        使用 keys 方法直接获取到 redis 中所有键
        Set<String> keys = jedis.keys("*");
        System.out.println(keys);
}

运行结果:


EXPIRE & TTL

public static void test4(Jedis jedis) throws InterruptedException {
        System.out.println("expire 和 ttl 的使用");
        jedis.flushAll();

        jedis.set("key","111");
//        使用 expire 方法给 key 设置过期时间 10秒
        jedis.expire("key",10);
//        休眠 3秒,再继续执行代码
        Thread.sleep(3000);
//        使用 ttl 方法获取到 key 的过期时间
        long time = jedis.ttl("key");
        System.out.println("此处预期 time = 7, 实际 time =  " + time);
}

运行结果:


TYPE

public static void test5(Jedis jedis) throws InterruptedException {
        System.out.println("type 的使用");
        jedis.flushAll();

        jedis.set("key","111");
        String type = jedis.type("key");
        System.out.println("此处预期 type = sting , 实际 type =  " + type);

        jedis.lpush("key2","111","222","333");
        String type2 = jedis.type("key2");
        System.out.println("此处预期 type2 = list , 实际 type2 =  " + type2);

        jedis.hset("key3","f1","111");
        String type3 = jedis.type("key3");
        System.out.println("此处预期 type3 = hash , 实际 type3 =  " + type3);

        jedis.sadd("key4","111","222","333");
        String type4 = jedis.type("key4");
        System.out.println("此处预期 type4 = set , 实际 type4 =  " + type4);

        jedis.zadd("key5",10,"zhangsan");
        String type5 = jedis.type("key5");
        System.out.println("此处预期 type5 = zset , 实际 type5 =  " + type5);
}

运行结果:

String 类型命令

?MGET & MSET

public static void test1(Jedis jedis) {
        System.out.println("mget 和 mset 的使用");
        jedis.flushAll();

        jedis.mset("key1","111","key2","222","key3","333");
//        此处多个 key 得到的 value 的顺序都是和 key 匹配的
//        如果某个 key 在 redis 上不存在,对应的 value 使用 null 表示
        List<String> values = jedis.mget("key1","key2","key100","key3");
        System.out.println("values: " + values);
}

运行结果:


GETRANGE & SETRANGE?

public static void test2(Jedis jedis) {
        System.out.println("getrange 和 setrange 的使用");
        jedis.flushAll();

        jedis.set("key","abcdefghijk");
        String result = jedis.getrange("key",2,5);
        System.out.println("此处预期 result = cdef, 实际 result = " + result);

        jedis.setrange("key",2,"xyz");
        String value = jedis.get("key");
        System.out.println("此处预期 value = abxyzfghijk, 实际 value = " + value);
}

运行结果:


APPEND

public static void test3(Jedis jedis) {
        System.out.println("append 的使用");
        jedis.flushAll();

        jedis.set("key","abcdef");
        jedis.append("key","ghij");

        String value = jedis.get("key");
        System.out.println("此处预期 value = abcdefghij, 实际 value = " + value);
}

运行结果:


INCR & DECR

public static void test4(Jedis jedis) {
        System.out.println("incr 和 decr 的使用");
        jedis.flushAll();

        jedis.set("key","100");
        
        long result = jedis.incr("key");
        System.out.println("此处预期 result = 101, 实际 result = " + result);
        
        String value = jedis.get("key");
        System.out.println("此处预期 value = 101, 实际 value = " + value);

        result = jedis.decr("key");
        System.out.println("此处预期 result = 100, 实际 result = " + result);

        value = jedis.get("key");
        System.out.println("此处预期 value = 100, 实际 value = " + value);
}

运行结果:

List 类型命令

LPUSH & LRANG?

public static void test1(Jedis jedis) {
        System.out.println("lpush、rpush 和 lrange 的使用");
        jedis.flushAll();

        jedis.lpush("key","111","222","333");

        jedis.rpush("key2","111","222","333");

        List<String> result = jedis.lrange("key",0,-1);
        System.out.println("采用 lpush 的 result = " +result);

        List<String> result2 = jedis.lrange("key2",0,-1);
        System.out.println("采用 rpush 的 result = " + result2);
}

运行结果:


LPOP & LPOP

import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

public class RedisDemoList {
    public static void test2(Jedis jedis) {
        System.out.println("lpop、rpop 的使用");
        jedis.flushAll();

        jedis.rpush("key","111","222","333");

        String result = jedis.lpop("key");
        System.out.println("采用 lpop 的预期 result = 111, 实际 result = " + result);

        result = jedis.rpop("key");
        System.out.println("采用 rpop 的预期 result = 333, 实际 result = " + result);
    }

    public static void main(String[] args) {
        JedisPool jedisPool = new JedisPool("tcp://127.0.0.1:8888");
        try (Jedis jedis = jedisPool.getResource()) {
            test2(jedis);
        }
    }
}

运行结果:


BLPOP & BRPOP

import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

import java.util.List;

public class RedisDemoList {
    public static void test3(Jedis jedis) {
        System.out.println("blpop 的使用");
        jedis.flushAll();

//        返回结果是一个 "二元组" 有个是从哪个 key 对应的 list 中删除的,一个删除的元素是什么
        List<String> results = jedis.blpop(100,"key");
        System.out.println("results.get(0) = " + results.get(0));
        System.out.println("results.get(1) = " + results.get(1));
    }

    public static void main(String[] args) {
        JedisPool jedisPool = new JedisPool("tcp://127.0.0.1:8888");
        try (Jedis jedis = jedisPool.getResource()) {
            test3(jedis);
        }
    }
}

运行结果:


LLEN

import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

public class RedisDemoList {
    public static void test4(Jedis jedis) {
        System.out.println("llen 的使用");
        jedis.flushAll();

        jedis.rpush("key","111","222","333");
        long len = jedis.llen("key");
        System.out.println("此处预期 len = 3, 实际 len = " + len);
    }

    public static void main(String[] args) {
        JedisPool jedisPool = new JedisPool("tcp://127.0.0.1:8888");
        try (Jedis jedis = jedisPool.getResource()) {
//            test3(jedis);
            test4(jedis);
        }
    }
}

运行结果:

Set 类型命令

SADD & SMEMBERS

public static void test1(Jedis jedis) {
        System.out.println("sadd 和 smembers 的使用");
        jedis.flushAll();

        jedis.sadd("key","111","222","333");
        Set<String> result = jedis.smembers("key");
        System.out.println("result: " + result);
}

运行结果:


SISMEMBERS

public static void test2(Jedis jedis) {
        System.out.println("sismembers 的使用");
        jedis.flushAll();

        jedis.sadd("key","111","222","333");
        boolean result = jedis.sismember("key","111");
        System.out.println("此处预期 result = true, 实际 result = " + result);
        result = jedis.sismember("key","100");
        System.out.println("此处预期 result = false, 实际 result = " + result);
}

运行结果:


SCARD

public static void test3(Jedis jedis) {
        System.out.println("scard 的使用");
        jedis.flushAll();

        jedis.sadd("key","111","222","333");
        long result = jedis.scard("key");
        System.out.println("此处预期 result = 3, 实际 result = " + result);
}

运行结果:


SPOP

public static void test4(Jedis jedis) {
        System.out.println("spop 的使用");
        jedis.flushAll();

        jedis.sadd("key","111","222","333","444","555");
        String result = jedis.spop("key");
        System.out.println("此处将随机删除一个元素, result = " + result);
}

运行结果:


SINTER

public static void test4(Jedis jedis) {
        System.out.println("spop 的使用");
        jedis.flushAll();

        jedis.sadd("key","111","222","333","444","555");
        String result = jedis.spop("key");
        System.out.println("此处将随机删除一个元素, result = " + result);
}

运行结果:


SINTERSTORE

public static void test6(Jedis jedis) {
        System.out.println("sinterstore 的使用");
        jedis.flushAll();

        jedis.sadd("key","111","222","333");
        jedis.sadd("key2","111","222","444");

        long len = jedis.sinterstore("key3","key","key2");
        System.out.println("此处预期 len = 2, 实际 len = " + len);

        Set<String> result = jedis.smembers("key3");
        System.out.println("result = " + result);
}

运行结果:

Hash 类型命令?

HSET & HGET

public static void test1(Jedis jedis) {
        System.out.println("hset 和 hget 的使用");
        jedis.flushAll();
//        一次性设置单个
        jedis.hset("key","f1","111");
//        一次性设置多个
        HashMap<String,String> fields = new HashMap<>();
        fields.put("f2","222");
        fields.put("f3","333");
        jedis.hset("key",fields);

        String result = jedis.hget("key","f1");
        System.out.println("此处预期 result = 111, 实际 result = " + result);

        result = jedis.hget("key","f100");
        System.out.println("此处预期 result = null, 实际 result = " + result);
}

运行结果:


HEXISTS

public static void test2(Jedis jedis) {
        System.out.println("hexists 的使用");
        jedis.flushAll();

        jedis.hset("key","f1","111");
        jedis.hset("key","f2","222");
        jedis.hset("key","f3","333");

        boolean result = jedis.hexists("key","f1");
        System.out.println("此处预期 result = ture, 实际 result = " + result);

        result = jedis.hexists("key","f100");
        System.out.println("此处预期 result = false, 实际 result = " + result);
}

运行结果:


HDEL

public static void test3(Jedis jedis) {
        System.out.println("hdel 的使用");
        jedis.flushAll();

        jedis.hset("key","f1","111");
        jedis.hset("key","f2","222");
        jedis.hset("key","f3","333");

        long result = jedis.hdel("key","f1","f2");
        System.out.println("此处预期 result = 1, 实际 result = " + result);

        boolean exists = jedis.hexists("key","f1");
        System.out.println("此处预期 exists = false, 实际 exists = " + exists);
        exists = jedis.hexists("key","f2");
        System.out.println("此处预期 exists = false, 实际 exists = " + exists);
}

运行结果:


HKEYS & HVALS

public static void test4(Jedis jedis) {
        System.out.println("hkeys 和 hvals 的使用");
        jedis.flushAll();

        jedis.hset("key","f1","111");
        jedis.hset("key","f2","111");
        jedis.hset("key","f3","333");

        Set<String> fields = jedis.hkeys("key");
        System.out.println("fields = " + fields);

        List<String> vals = jedis.hvals("key");
        System.out.println("vals = " + vals);
}

运行结果:


HMGET & HMSET

public static void test5(Jedis jedis) {
        System.out.println("hmget 和 hmset 的使用");
        jedis.flushAll();

        HashMap<String,String> map = new HashMap<>();
        map.put("f1","111");
        map.put("f2","222");
        map.put("f3","333");
        jedis.hmset("key",map);

        List<String> vals = jedis.hmget("key","f3","f1","f2");
//        此时返回元素的顺序一定为 我们自己所指定 field 的先后顺序
        System.out.println("此处预期 vals = [333,111,222], 实际 vals = " + vals);
}

运行结果:

?ZSet 类型命令

ZADD & ZRANGE

public static void test1(Jedis jedis) {
        System.out.println("zadd 和 zrange 的使用");
        jedis.flushAll();

        jedis.zadd("key",10,"zhangsan");
        Map<String,Double> map = new HashMap<>();
        map.put("lisi",20.0);
        map.put("wangwu",30.0);
        jedis.zadd("key",map);

        List<String> members = jedis.zrange("key",0,-1);
        System.out.println("members = " + members);

        List<Tuple> membersWithScore = jedis.zrangeWithScores("key",0,-1);
        System.out.println("membersWithScore = " + membersWithScore);

        String member = membersWithScore.get(0).getElement();
        double score = membersWithScore.get(0).getScore();
        System.out.println("member = " + member + ", score" + score);
}

运行结果:


ZCARD

public static void test2(Jedis jedis) {
        System.out.println("zcard 的使用");
        jedis.flushAll();

        jedis.zadd("key",10,"zhangsan");
        jedis.zadd("key",20,"lisi");
        jedis.zadd("key",30,"wangwu");

        long len = jedis.zcard("key");
        System.out.println("此处预期 len = 3, 实际 len = " + len);
}

运行结果:


ZREM

public static void test3(Jedis jedis) {
        System.out.println("zrem 的使用");
        jedis.flushAll();

        jedis.zadd("key",10,"zhangsan");
        jedis.zadd("key",20,"lisi");
        jedis.zadd("key",30,"wangwu");

        long n = jedis.zrem("key","zhangsan");
        System.out.println("此处预期 n = 1, 实际 n = " + n);

        List<Tuple> membersWithScore = jedis.zrangeWithScores("key",0,-1);
        System.out.println("membersWithScore = " + membersWithScore);
}

运行结果:


ZSCORE

public static void test4(Jedis jedis) {
        System.out.println("zscore 的使用");
        jedis.flushAll();

        jedis.zadd("key",10,"zhangsan");
        jedis.zadd("key",20,"lisi");
        jedis.zadd("key",30,"wangwu");

        Double score = jedis.zscore("key","zhangsan");
        System.out.println("此处预期 score = 10.0, 实际 n = " + score);

        score = jedis.zscore("key","zhaoliu");
        System.out.println("此处预期 score = null, 实际 n = " + score);
}

运行结果:


ZRANK

public static void test5(Jedis jedis) {
        System.out.println("zrank 的使用");
        jedis.flushAll();

        jedis.zadd("key",10,"zhangsan");
        jedis.zadd("key",20,"lisi");
        jedis.zadd("key",30,"wangwu");

        Long rank = jedis.zrank("key","zhangsan");
        System.out.println("此处预期 score = 1, 实际 n = " + rank);

        rank = jedis.zrank("key","zhaoliu");
        System.out.println("此处预期 score = null, 实际 n = " + rank);
}

运行结果:

文章来源:https://blog.csdn.net/weixin_63888301/article/details/135563391
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