docs: public void setPingIntervalMsec(long pingIntervalMsec) {
          lock.lock();
          try {
              this.pingIntervalMsec = pingIntervalMsec;
              ListenableScheduledFuture<?> task = vPingTask;
              if (task != null)
                  task.cancel(false);
              setupPinging();
          } finally {
              lock.unlock();
          }
      }