code: public synchronized void releaseServerLock() {
          if (serverLock != null) {
              try {
                  serverLock.release();
              } catch (IOException e) {
              } finally {
                  Utils.tryToClose(lockFileChannel);
              }
              serverLock = null;
              lockFileChannel = null;
          }
      }
docs: Release server lock.
  
  @throws IOException