目录

  • JedisAPI基本使用
  • 1.导入相关依赖
  • 2.连接成功测试
  • 3.常用API
  • 3.1 key相关操作
  • 3.2 String
  • 3.3 List
  • 3.4 Set
  • 3.5 Hash
  • Jedis实现Redis事务


以下是Redis相关笔记总结，方便自己以后复习，同时也希望对大家有所帮助。

内容

地址链接

Redis在Linux环境下的详细安装教程

Redis中五大基本数据类型和三种特殊数据类型

Redis中基本事务操作及乐观锁的实现

Java中使用JedisAPI操作Redis中五大基本数据类型

Spring boot整合Redis（入门教程）

Redis主从复制详解（入门教程）

Spring boot整合Redis实现发布订阅（超详细）

Redis执行save命令时报错ERR

JedisAPI基本使用

1.导入相关依赖

Maven仓库

<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>2.4.2</version>
 </dependency>

2.连接成功测试

本文ip相关信息隐去，在本地测试时将程序中*替换成ip即可

public class JedisTest {
    public static void main(String[] args) {
         Jedis jedis = new Jedis("***.***.***.***");
        if (jedis != null){
            jedis.auth("root");
            System.out.println(jedis.ping());
        }
    }
}

jredis官方文档 jredis api_jredis官方文档

3.常用API

3.1 key相关操作

public class JedisString {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("***.***.***.***");
        jedis.auth("root");

        String s = jedis.flushDB();
        System.out.println("清空数据（正确返回ok）：" + s);
        Boolean username = jedis.exists("username");
        System.out.println("判断某个键是否存在（返回Boolen类型）" + username);

        System.out.println("新增<'username','bbx'>的键值对：" + jedis.set("username", "bbx"));
        System.out.println("新增<'password','password'>的键值对：" + jedis.set("password", "password"));
        System.out.println("新增<'age','18'>的键值对：" + jedis.set("password", "18"));
        Set<String> keys = jedis.keys("*");
        System.out.println("所有的key：" + 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username的键，改为name：" + 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(1));
        System.out.println("删除当前选择数据库中所有的key:" + jedis.flushDB());
        System.out.println("返回当前选择数据库中所有的key的数目:" + jedis.dbSize());
        System.out.println("删除当前所有数据库中所有的key:" + jedis.flushAll());
    }
}

运行结果：

jredis官方文档 jredis api_jredis官方文档_02

3.2 String

public class JedisTest {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("***.***.***.***");
        jedis.auth("root");
        System.out.println(jedis.ping());

        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("获取建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("=============批量增加数据===============");
        System.out.println("增加多个键值对："+jedis.mset("key01","value01","key02","value02","key03","value03","key04","value04"));
        System.out.println("获取多个键值对："+jedis.mget("key01","key02"));
        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("=====================分布式锁，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("获取key2的值的字符串："+jedis.getrange("key2",2,4));

    }
}

运行结果:

jredis官方文档 jredis api_jredis官方文档_03

3.3 List

public class JedisList {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("***.***.***.***",6379);
        jedis.auth("root");
        jedis.flushDB();
        System.out.println("=============添加一个List===============");
        jedis.lpush("collections","ArrayList","Vector" ,"Stack","HashMap","WeakHashMap","LinkHasMap","HashMap");
        jedis.lpush("collections","HashSet");
        jedis.lpush("collections","TreeMap");
        System.out.println("collections的内容："+jedis.lrange("collections",0,-1));
        System.out.println("collections区间0-3的元数；"+jedis.lrange("collections",0,3));
        //删除列表指定的值，第二个参数为删除的个数（有重复时），后push进入的值先被删除，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("删除下标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的列表出栈（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","HashMap"));
        System.out.println("collections的内容："+jedis.lrange("collections",0,-1));
        System.out.println("collections的列表出栈（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,"LinkHashMap")));
        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"));
        List<String> sortedList = jedis.sort("sortedList");
        System.out.println("sortedList排序后:"+sortedList);
    }
}

运行结果：

jredis官方文档 jredis api_linux_04

3.4 Set

public class JedisSet {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("***.***.***.***",6379);
        jedis.auth("root");
        System.out.println("==================set测试，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("第一次插入e6:"+jedis.sadd("eleSet","e6"));
        System.out.println("第二次插入e6:"+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,e6:"+jedis.srem("eleSet","e7","e6"));
        System.out.println("eleSet的所有元素为"+jedis.smembers("eleSet"));
        System.out.println("随机移除集合中的一个元素："+jedis.spop("eleSet"));
        System.out.println("随机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("==========================================================================");
        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("eleSet1中删除e1并存入eleSet3中；"+jedis.smove("eleSet1","eleSet3","e1"));
        System.out.println("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"));
        //求交集并将交集保存到dstkey的集合
        jedis.sinterstore("eleSet4","eleSet1","eleSet2");
        System.out.println("eleSet4中的元素:"+jedis.smembers("eleSet4"));
    }
}

运行结果：

jredis官方文档 jredis api_后端_05

3.5 Hash

public class JedisHash {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("***.***.***.***", 6379);
        jedis.auth("root");
        jedis.flushDB();
        HashMap<String, String> 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添加key为key5，value为value5的元素
        jedis.hset("hash","key5","value5");
        System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));
        System.out.println("散列hash的所有键为："+jedis.hkeys("hash"));
        System.out.println("散列hash的所有值为："+jedis.hvals("hash"));

    }

}

运行结果：

jredis官方文档 jredis api_linux_06

Jedis实现Redis事务

事务相关的命令有：MULTI、EXEC、DISCARD、WATCH、UNWATCH。

public class JedisTX {
    public static void main(String[] args) {
        Jedis jedis = new Jedis("***.***.***.***");
        jedis.auth("root");

        //清楚当前数据库
        jedis.flushDB();
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("hello","world");
        jsonObject.put("name","bbx");
        //开启事务
        Transaction multi = jedis.multi();
        String result = jsonObject.toJSONString();
        //监控，乐观锁
       // jedis.watch(result);
        try {
            multi.set("user1", result);
            multi.set("user2", result);
            //执行事务
            multi.exec();
        }catch (Exception e){
            //如果事务执行失败就进行解锁
            jedis.unwatch(); 
            //放弃事务
            multi.discard();
            e.printStackTrace();
        }finally {
            System.out.println(jedis.get("user1"));
            System.out.println(jedis.get("user2"));
            //关闭连接
            jedis.close();
        }

    }

}

代码分析：

  1. jedis.multi();开启Redis的事务
  2. jedis.watch(result);对result进行监控
  3. 编写所需命令入队列 multi.set(“user1”,result); multi.set(“user2”,result)；
  4. 执行 multi.exec()时，Redis会执行队列中的命令
    这个时候如果事务执行成功，就会finally中就会输出get到的值，
    如果事务执行失败，就会进行异常的捕获，同时将监控进行解锁 jedis.unwatch();，并且放弃本次事务 multi.discard()，
    最后不管事务执行是否成功，都要将Jedis进行关闭。

运行结果：

jredis官方文档 jredis api_redis_07