code: public ClassificationMetrics validate(Map<Object, URI> datasets) {
          TrainingParameters trainingParameters = (TrainingParameters) knowledgeBase.getTrainingParameters();
  
          //build the testDataset
          Dataframe testDataset = Dataframe.Builder.parseTextFiles(
                  datasets,
                  AbstractTextExtractor.newInstance(trainingParameters.getTextExtractorParameters()),
                  knowledgeBase.getConfiguration()
          );
  
          ClassificationMetrics vm = validate(testDataset);
  
          testDataset.close();
  
          return vm;
      }
docs: It validates the 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 data files should contain one example
  per row.
  
  @param datasets
  @return