Redis Thread Safety Discussion

Package com.me.config;

Import Redis.clients.jedis.Jedis;
Import Redis.clients.jedis.JedisPool;

/**
* Project:me
* Package:com.me.config
* DATE:2017/11/22 19:30
* Author:simeon
*/

Class Demo extends Thread
{
    public void Run ()
    {
        Jedis jedis1 = new Jedis ();
        for (int i=0;i<100;i++) {
            int num = Integer.parseint (jedis1.get ("num"));
            num = num + 1;
            Jedis1.set ("num", num+ "");
            System.out.println (jedis1.get ("num"));
        }
    }

}

public class test{

    public static void Main (String ... args) {
        Jedis Jedis = new Jedis ();
        Jedis.set ("num", "1");
        New Demo (). Start ();
        New Demo (). Start ();
    }

}
One num is stored first, and the value is 1. Run 2 threads, each of which is 100 cycles +1.

Reasoning if thread safety, two threads should be mutually exclusive when running, that is, one thread is running and the other is in a blocking state, so the output should be 200.
But the result output is not 200. So Redis is not thread safe.

Redis Thread Safety discussion