code: public void fit(Map<Object, URI> datasets) {
          TrainingParameters tp = (TrainingParameters) knowledgeBase.getTrainingParameters();
          Dataframe trainingData = Dataframe.Builder.parseTextFiles(datasets,
                  AbstractTextExtractor.newInstance(tp.getTextExtractorParameters()),
                  knowledgeBase.getConfiguration()
          );
          
          fit(trainingData);
          
          trainingData.close();
      }
docs: Trains a Machine Learning modeler using the provided dataset files. The data
  map should have as index the names of each class and as values the URIs
  of the training files. The training files should contain one training example
  per row.
  
  @param datasets