public class JedisPoolUtil {
    private static volatile JedisPool jedisPool = null;

    private JedisPoolUtil() {
    }

    public static JedisPool getJedisPoolInstance() {
        if (null == jedisPool) {
            synchronized (JedisPoolUtil.class) {
                if (null == jedisPool) {
                    JedisPoolConfig poolConfig = new JedisPoolConfig();
                    poolConfig.setMaxTotal(200);
                    poolConfig.setMaxIdle(32);
                    poolConfig.setMaxWaitMillis(100*1000);
                    poolConfig.setBlockWhenExhausted(true);
                    poolConfig.setTestOnBorrow(true);  // ping  PONG
                    jedisPool = new JedisPool(poolConfig, "114.116.246.5", 6379, 60000,"Atcomsn1314");
                }
            }
        }
        return jedisPool;
    }

    public static void release(Jedis jedis) {
        if(null != jedis){
            jedis.close();
        }
    }

}

public class SecKill_redis {

    public static void main(String[] args) {
        Jedis jedis =new Jedis("192.168.44.168",6379);
        System.out.println(jedis.ping());
        JedisPoolUtil.release(jedis);
    }

    //秒杀过程
    public static boolean doSecKill(String uid,String prodid) throws IOException {
        //1 uid和prodid非空判断
        if(uid == null || prodid == null) {
            return false;
        }

        //2 连接redis
        //Jedis jedis = new Jedis("192.168.44.168",6379);
        //设置密码
        //jedis.auth("123456");
        //通过连接池得到jedis对象
        JedisPool jedisPoolInstance = JedisPoolUtil.getJedisPoolInstance();
        Jedis jedis = jedisPoolInstance.getResource();

        //3 拼接key
        // 3.1 库存key
        String kcKey = "sk:"+prodid+":qt";
        // 3.2 秒杀成功用户key
        String userKey = "sk:"+prodid+":user";

        //监视库存
        jedis.watch(kcKey);

        //4 获取库存，如果库存null，秒杀还没有开始
        String kc = jedis.get(kcKey);
        if(kc == null) {
            System.out.println("秒杀还没有开始，请等待");
            //释放jedis（close）
            JedisPoolUtil.release(jedis);
            return false;
        }

        // 5 判断用户是否重复秒杀操作（sismember为判断set中是否存在，返回boolean类型）
        if(jedis.sismember(userKey, uid)) {
            System.out.println("已经秒杀成功了，不能重复秒杀");
            JedisPoolUtil.release(jedis);
            return false;
        }

        //6 判断如果商品数量，库存数量小于1，秒杀结束
        if(Integer.parseInt(kc)<=0) {
            System.out.println("秒杀已经结束了");
            JedisPoolUtil.release(jedis);
            return false;
        }

        //7 秒杀过程
        //使用事务
        Transaction multi = jedis.multi();

        //组队操作
        multi.decr(kcKey);
        multi.sadd(userKey,uid);

        //执行
        List<Object> results = multi.exec();

        if(results == null || results.size()==0) {
            System.out.println("秒杀失败了....");
            JedisPoolUtil.release(jedis);
            return false;
        }

        //7.1 库存-1
        //jedis.decr(kcKey);
        //7.2 把秒杀成功用户添加清单里面
        //jedis.sadd(userKey,uid);

        System.out.println("秒杀成功了..");
        JedisPoolUtil.release(jedis);
        return true;
    }
}

public class SecKill_redisByScript {
    
    private static final  org.slf4j.Logger logger =LoggerFactory.getLogger(SecKill_redisByScript.class) ;

    public static void main(String[] args) {
        JedisPool jedispool =  JedisPoolUtil.getJedisPoolInstance();
 
        Jedis jedis=jedispool.getResource();
        System.out.println(jedis.ping());
        
        Set<HostAndPort> set=new HashSet<HostAndPort>();

    //    doSecKill("201","sk:0101");
    }

    //获取参数KEYS[i]
    static String secKillScript ="local userid=KEYS[1];\r\n" + 
            "local prodid=KEYS[2];\r\n" +
            //..prodid..类似拼接字符串
            "local qtkey=‘sk:‘..prodid..\":qt\";\r\n" + 
            "local usersKey=‘sk:‘..prodid..\":usr\";\r\n" + 
            "local userExists=redis.call(\"sismember\",usersKey,userid);\r\n" +
            //判断是否存在该用户，即已买过
            "if tonumber(userExists)==1 then \r\n" + 
            "   return 2;\r\n" + 
            "end\r\n" + 
            "local num= redis.call(\"get\" ,qtkey);\r\n" +
            //判断是否还有库存
            "if tonumber(num)<=0 then \r\n" + 
            "   return 0;\r\n" + 
            "else \r\n" + 
            "   redis.call(\"decr\",qtkey);\r\n" + 
            "   redis.call(\"sadd\",usersKey,userid);\r\n" + 
            "end\r\n" + 
            "return 1" ;
             
    static String secKillScript2 = 
            "local userExists=redis.call(\"sismember\",\"{sk}:0101:usr\",userid);\r\n" +
            " return 1";

    public static boolean doSecKill(String uid,String prodid) throws IOException {

        JedisPool jedispool =  JedisPoolUtil.getJedisPoolInstance();
        Jedis jedis=jedispool.getResource();

        //将脚本转换为函数
        String sha1=  jedis.scriptLoad(secKillScript);
        //给脚本函数传入参数，调用函数
        Object result= jedis.evalsha(sha1, 2, uid,prodid);

          String reString=String.valueOf(result);
        if ("0".equals( reString )  ) {
            System.err.println("已抢空！！");
        }else if("1".equals( reString )  )  {
            System.out.println("抢购成功！！！！");
        }else if("2".equals( reString )  )  {
            System.err.println("该用户已抢过！！");
        }else{
            System.err.println("抢购异常！！");
        }
        jedis.close();
        return true;
    }
}