問題描述

思路是用redis的setNX來獲取鎖，并加上超時時間，在使用完后刪除key來釋放鎖，沒獲取到鎖的就一直輪詢setNX來獲取鎖直到獲取成功，但是每次刪除完key之后并沒有線程獲取到了鎖。不知道是什么原因。

代碼放出來：

public class RedisLock {public static void lock(String key){lock(key,60); }public static void lock(String key,int time){Jedis jedis = RedisUtil.getClient();try { for (;;) {//這一步在unlock以后還一直返回的NULL并沒有返回OK?。?！String result = jedis.set(key, '1', 'NX', 'EX', time);System.out.println(result);if('OK'.equals(result)){ break;}Thread.sleep(300); }} catch (Exception e) { e.printStackTrace();} finally{ jedis.close();} }public static void unLock(String key){Jedis jedis = RedisUtil.getClient();try { jedis.del(key);} catch (Exception e) { e.printStackTrace();} finally{ jedis.close();} }public static void main(String[] args) throws Exception{System.out.println(RedisUtil.getClient().del('seckill'));//開啟100條線程去搶購1000個商品for (int i = 0; i < 100; i++) { new SeckillThread(i).start();}while(Thread.activeCount()>1){ Thread.sleep(1000);}System.out.println('還剩商品數(shù)量：'+SeckillServiceImpl.goodNum); }}class SeckillServiceImpl{//商品總數(shù) public static int goodNum = 1000;public void kill(){if(goodNum>0){ goodNum--;} }public int getGoodNum(){return goodNum; }}class SeckillThread extends Thread{ private int i;public SeckillThread(int i) {this.i = i; } @Override public void run() {try { SeckillServiceImpl seckillService = new SeckillServiceImpl(); System.out.println('線程['+i+']加鎖'); RedisLock.lock('seckill'); seckillService.kill();} catch (Exception e) { e.printStackTrace();} finally { System.out.println('線程['+i+']釋放鎖'); RedisLock.unLock('seckill');} } }

問題解答

用Redisson吧

把你的kill方法寫出來

先查查為什么一直是null吧