### Question:
MentionAnnotator extends Annotator { public MentionAnnotator() { } MentionAnnotator();  MentionAnnotator(Tagger root); @Override MentionTagger getTagger(); @Override String toString(); @Override void annotate(Collection<Document> docs); void trainModel(Dataset train, Dataset test, WordHelpers.Language lang); void trainModel(Dataset train, Annotation.Source annotationSource, WordHelpers.Language lang); void trainModel(Dataset train, Annotation.Source annotationSource, WordHelpers.Language lang, int limitExamples, boolean incremental, boolean randomize); void trainModelEarlyStopping(Dataset train, Dataset validation, Annotation.Source annotationSource, WordHelpers.Language lang, int epochSize, int minEpochs, int maxEpochs, int maxEpochsWithNoImprovement); void writeBestModel(Resource path, String name); void trainModel(Collection<Sentence> sentences, Annotation.Source tagSource, WordHelpers.Language lang);  }### Answer:
@Test public void testMentionAnnotator() throws IOException { Resource path = Resource.createTempDirectory(); LetterNGramEncoder trigram = new LetterNGramEncoder("TRI") .setN(3); trigram.trainModel(data.getDocuments()); trigram.saveModel(path, "trigram"); MentionTagger tagger = new MentionTagger("BLSTM"); tagger.setTagset(BIO2Tag.class, "TEST"); tagger.setEncoders(Lists.newArrayList(trigram)); tagger.setModelParams(50, 20, 1, 0.01); tagger.setTrainingParams(5, 1, false); tagger.trainModel(data); tagger.saveModel(path, "ner"); MentionAnnotator ann = new MentionAnnotator(tagger); ann.addComponent(trigram); ann.getProvenance() .setLanguage("en") .setTask("NER") .setDataset("en_Test") .setFeatures("tri"); ann.writeTrainLog(path); ann.writeTestLog(path); ann.writeModel(path, "ner_test"); assertEquals("MentionAnnotator_NER@en_Test+tri_" + ann.getProvenance().getDate(), ann.getProvenance().toString()); assertEquals(MentionAnnotator.class, ann.getClass()); assertEquals(MentionTagger.class, ann.getTagger().getClass()); assertTrue(ann.isModelAvailable()); assertTrue(ann.isModelAvailableInChildren()); ann.getTagger().tag(data.getDocuments()); Annotator test = AnnotatorFactory.loadAnnotator(path); assertEquals(MentionAnnotator.class, test.getClass()); assertEquals(MentionTagger.class, test.getTagger().getClass()); assertTrue(test.isModelAvailable()); assertTrue(test.isModelAvailableInChildren()); test.getTagger().tag(data.getDocuments()); assertEquals(ann.getProvenance().toString(), test.getProvenance().toString()); }