How to use

LanguageDetectorCrossValidator

in

opennlp.tools.langdetect

try {
 LanguageDetectorFactory factory = LanguageDetectorFactory.create(params.getFactory());
 validator = new LanguageDetectorCrossValidator(mlParams,
   factory, listenersArr);
 validator.evaluate(sampleStream, params.getFolds());
} catch (IOException e) {
 throw new TerminateToolException(-1,
System.out.println("Accuracy: " + validator.getDocumentAccuracy() + "\n" +
  "Number of documents: " + validator.getDocumentCount());

@Test
public void evaluate() throws Exception {
 TrainingParameters params = new TrainingParameters();
 params.put(TrainingParameters.ITERATIONS_PARAM, 100);
 params.put(TrainingParameters.CUTOFF_PARAM, 5);
 params.put("PrintMessages", false);
 final AtomicInteger correctCount = new AtomicInteger();
 final AtomicInteger incorrectCount = new AtomicInteger();
 LanguageDetectorCrossValidator cv = new LanguageDetectorCrossValidator(params,
   new LanguageDetectorFactory(), new LanguageDetectorEvaluationMonitor() {
    @Override
    public void correctlyClassified(LanguageSample reference,
                    LanguageSample prediction) {
     correctCount.incrementAndGet();
    }
    @Override
    public void missclassified(LanguageSample reference,
                  LanguageSample prediction) {
     incorrectCount.incrementAndGet();
    }
   });
 LanguageDetectorSampleStream sampleStream = LanguageDetectorMETest.createSampleStream();
 cv.evaluate(sampleStream, 2);
 Assert.assertEquals(99, cv.getDocumentCount());
 Assert.assertEquals(0.98989898989899, cv.getDocumentAccuracy(), 0.01);
}

try {
 LanguageDetectorFactory factory = LanguageDetectorFactory.create(params.getFactory());
 validator = new LanguageDetectorCrossValidator(mlParams,
   factory, listenersArr);
 validator.evaluate(sampleStream, params.getFolds());
} catch (IOException e) {
 throw new TerminateToolException(-1,
System.out.println("Accuracy: " + validator.getDocumentAccuracy() + "\n" +
  "Number of documents: " + validator.getDocumentCount());

try {
 LanguageDetectorFactory factory = LanguageDetectorFactory.create(params.getFactory());
 validator = new LanguageDetectorCrossValidator(mlParams,
   factory, listenersArr);
 validator.evaluate(sampleStream, params.getFolds());
} catch (IOException e) {
 throw new TerminateToolException(-1,
System.out.println("Accuracy: " + validator.getDocumentAccuracy() + "\n" +
  "Number of documents: " + validator.getDocumentCount());