code: protected void connectServiceUpIsRunning() {
          serviceProcessIsRunning = FunctionFeed.builder()
                  .entity(this)
                  .period(Duration.FIVE_SECONDS)
                  .poll(new FunctionPollConfig<Boolean, Boolean>(SERVICE_PROCESS_IS_RUNNING)
                          .onException(Functions.constant(Boolean.FALSE))
                          .callable(new Callable<Boolean>() {
                              public Boolean call() {
                                  return getDriver().isRunning();
                              }
                          }))
                  .build();
      }
docs: For connecting the {@link #SERVICE_UP} sensor to the value of the
  {@code getDriver().isRunning()} expression.
  <p/>
  Should be called inside {@link #connectSensors()}.
  
  @see #disconnectServiceUpIsRunning()