SpringBoot integration实现分布式锁的示例详解

// 分布式锁
implementation 'org.springframework.boot:spring-boot-starter-integration'
implementation('org.springframework.integration:spring-integration-redis')

@Bean
open fun redisLockRegistry(redisConnectionFactory: RedisConnectionFactory): RedisLockRegistry {

    return RedisLockRegistry(redisConnectionFactory, "fcDistroLock", 20000L)
}

Lock lock = ...;
if (lock.tryLock(time)) {
  try {
    // manipulate protected state
  } finally {
    lock.unlock();
  }
} else {
  // perform alternative actions
}}

@Scheduled(cron = "0 0 0/1 * * ?")
fun scheduleRemoveRedisLock() {

    redisLockRegistry.expireUnusedOlderThan(1000 * 60 * 60)
}

public boolean tryLock(long time, TimeUnit unit) throws InterruptedException {
   long now = System.currentTimeMillis();
   if (!this.localLock.tryLock(time, unit)) { // 获取本地互斥锁
      return false;
   }
   try {
      long expire = now + TimeUnit.MILLISECONDS.convert(time, unit);
      boolean acquired;
      while (!(acquired = obtainLock()) && System.currentTimeMillis() < expire) { //NOSONAR
         Thread.sleep(100); //NOSONAR 防止请求过快，进行100Ms的休眠
      }
      if (!acquired) {
         this.localLock.unlock();
      }
      return acquired;
   }
   catch (Exception e) {
      this.localLock.unlock();
      rethrowAsLockException(e);
   }
   return false;
}

private static final String OBTAIN_LOCK_SCRIPT =
      "local lockClientId = redis.call('GET', KEYS[1])\n" +
            "if lockClientId == ARGV[1] then\n" +
            "  redis.call('PEXPIRE', KEYS[1], ARGV[2])\n" +
            "  return true\n" +
            "elseif not lockClientId then\n" +
            "  redis.call('SET', KEYS[1], ARGV[1], 'PX', ARGV[2])\n" +
            "  return true\n" +
            "end\n" +
            "return false";