TransferLearningHelper : how to classify single image

Hi, I am trying to classify a single image after creating a model with the “TransferLearningHelper” class. The examples on the dl4j repository just shows how to evaluate the test data set, but does not show how to classify a single image read from the file system , and how to save the vgg16 model - did I understand correctly that after calling the

transferLearningHelper.fitFeaturized(trainiter.next())

the vgg16 model is automatically updated , and when I save this model that will be the trained model to use later ? Do I have to use the
transferLearningHelper.outputFromFeaturized(...)
to classify a single image ?