code: public static GISModel trainModel(EventStream eventStream,
                                        int iterations,
                                        int cutoff) {
          return trainModel(eventStream, iterations, cutoff, false,PRINT_MESSAGES);
      }
docs: Train a model using the GIS algorithm.
  
  @param eventStream The EventStream holding the data on which this model
  will be trained.
  @param iterations  The number of GIS iterations to perform.
  @param cutoff      The number of times a feature must be seen in order
  to be relevant for training.
  @return The newly trained model, which can be used immediately or saved
  to disk using an opennlp.maxent.io.GISModelWriter object.