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参考文章:https://blog.csdn.net/pfnie/article/details/52234735#commentBox
public class RedisUtil {
//失效时间
public static int ONE_DAY = 60 * 60 * 24;
//锁的过期时间,秒
private static long LOCK_EXPIRE = 60L;
//锁的请求超时时间
private static long LOCK_TIME_OUT = 10L * 1000000000L;
//锁名称
private static String LOCK_KEY = "lock";
//锁的值
private static String LOCK_VALUE = "1";
public void lock(StringRedisTemplate template) {
// 上锁时的时间
long nowTime = System.nanoTime();
//等待时间是否超时
Random r = new Random();
RedisConnection connection = template.getConnectionFactory().getConnection();
try {
long l = System.nanoTime() - nowTime;
while (l < LOCK_TIME_OUT) {
// 锁是否存在
if (connection.setNX(LOCK_KEY.getBytes(), LOCK_VALUE.getBytes())) {
//锁不存在,设置锁的有效期,然后跳出循环,上锁方法结束
template.expire(LOCK_KEY, LOCK_EXPIRE, TimeUnit.SECONDS);
break;
} else {
//锁存在,则重试。设置随机的延迟时间,避免不同客户端同时重试导致谁都无法拿到锁
Thread.sleep(5, r.nextInt(100));
l = System.nanoTime() - nowTime;
}
}
if (l > LOCK_TIME_OUT) {
System.out.println("超时");
System.out.println("执行时间:" + l);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
connection.close();
}
}
public void unLock(StringRedisTemplate template) {
template.delete(LOCK_KEY);
}
}