Jedis06


简介

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,必须对Jedis熟悉才能 写成漂亮的代码

测试联通

1、新建一个普通的Maven项目

2、导入redis的依赖!

 

    
    
        redis.clients
        jedis
        3.2.0
    
    
    
        com.alibaba
        fastjson
        1.2.76
    

3、编写测试代码

package com.edgar;

import redis.clients.jedis.Jedis;

public class TestPing {

    public static void main(String[] args) {
        // 1、new Jedis 对象即可
        Jedis jedis = new Jedis("127.0.0.1",6379);
        // jedis 所有的命令就是我们之前学习的所有指令!所以之前的指令学习很重要!
        System.out.println(jedis.ping());
    }
}

4、启动redis服务

5、启动测试,结果

HWiMbn.png

常用API

基本操作

package com.edgar;

import redis.clients.jedis.Jedis;

public class TestPing {

    public static void main(String[] args) {
        // 1、new Jedis 对象即可
        Jedis jedis = new Jedis("127.0.0.1",6379);
        // jedis 所有的命令就是我们之前学习的所有指令!所以之前的指令学习很重要!
        System.out.println(jedis.ping());
    }
}

对key操作的命令

package com.edgar;

import redis.clients.jedis.Jedis;

import java.util.Set;

public class TestKey {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("127.0.0.1", 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','kuangshen'>的键值 对:" + jedis.set("username", "kuangshen"));
        System.out.println("新增<'password','password'>的键值 对:" + jedis.set("password", "password"));
        System.out.print("系统中所有的键如下:");
        Set keys = jedis.keys("*");
        System.out.println(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("查看键username所存储的值的类 型:" + jedis.type("username"));
        System.out.println("随机返回key空间的一个:" + jedis.randomKey());
        System.out.println("重命名key:" + jedis.rename("username", "name"));
        System.out.println("取出改后的name:" + jedis.get("name"));
        System.out.println("按索引查询:" + jedis.select(0));
        System.out.println("删除当前选择数据库中的所有key:" + jedis.flushDB());
        System.out.println("返回当前数据库中key的数目:" + jedis.dbSize());
        System.out.println("删除所有数据库中的所有key:" + jedis.flushAll());
    }
}

对String操作的命令

package com.edgar;

import redis.clients.jedis.Jedis;

import java.util.concurrent.TimeUnit;

public class TestString {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("127.0.0.1", 6379);

        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"));
        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("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"));
        try {
            TimeUnit.SECONDS.sleep(3);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println(jedis.get("key3"));

        System.out.println("===========获取原值,更新为新值==========");
        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));
    }
}

对List操作命令

package com.edgar;

import redis.clients.jedis.Jedis;

public class TestList {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("127.0.0.1", 6379);
        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,end为-1表示查询全部
        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));
    }
}

对Set的操作命令

package com.edgar;

import redis.clients.jedis.Jedis;

public class TestSet {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("127.0.0.1", 6379);
        jedis.flushDB();
        System.out.println("============向集合中添加元素(不重复) ============");
        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"));//移到集合元素
        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
        jedis.sinterstore("eleSet4", "eleSet1", "eleSet2");//求交集并将交集保存到dstkey的集合
        System.out.println("eleSet4中的元素:" + jedis.smembers("eleSet4"));
    }
}

对Hash的操作命令

package com.edgar;

import redis.clients.jedis.Jedis;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class TestHash {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("127.0.0.1", 6379);
        jedis.flushDB();
        Map map = new HashMap<>();
        map.put("key1", "value1");
        map.put("key2", "value2");
        map.put("key3", "value3");
        map.put("key4", "value4");
        //添加名称为hash(key)的hash元素
        jedis.hmset("hash", map);
        //向名称为hash的hash中添加key为key5,value为value5元素
        jedis.hset("hash", "key5", "value5");
        System.out.println("散列hash的所有键值对为:" + jedis.hgetAll(" hash"));//return MapSystem.out.println(" 散列hash的所有键为:"+jedis.hkeys(" hash"));//return Set
        System.out.println("散列hash的所有值为:" + jedis.hvals("hash"));//return List
        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"));
    }
}

事务

基本操作

package com.edgar;

import com.alibaba.fastjson.JSONObject;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.Transaction;

public class TestTX {

    public static void main(String[] args) {
        Jedis jedis = new Jedis("127.0.0.1", 6379);
        jedis.flushDB();

        JSONObject jsonObject = new JSONObject();
        jsonObject.put("hello", "world");
        jsonObject.put("name", "edgar");
        // 开启事务
        Transaction multi = jedis.multi();
        String result = jsonObject.toJSONString();
        // jedis.watch("user1","user2"); // 乐观锁
        try {
            multi.set("user1", result);
            multi.set("user2", result);
            int i = 1 / 0; // 代码抛出异常,事务执行失败!
            multi.exec(); // 执行事务!
        } catch (Exception e) {
            multi.discard(); // 放弃事务
            e.printStackTrace();
        } finally {
            System.out.println(jedis.get("user1"));
            System.out.println(jedis.get("user2"));
            jedis.close(); // 关闭连接
        }


    }
}