code: public final void evalError() {
      final List<EvaluationMonitor<POSSample>> listeners = new LinkedList<EvaluationMonitor<POSSample>>();
      listeners.add(new POSEvaluationErrorListener());
      final POSEvaluator evaluator = new POSEvaluator(this.posTagger,
          listeners.toArray(new POSTaggerEvaluationMonitor[listeners.size()]));
      try {
        evaluator.evaluate(this.testSamples);
      } catch (IOException e) {
        e.printStackTrace();
      }
      System.out.println(evaluator.getWordAccuracy());
    }
docs: Evaluate and print every error.