### Question:
UpdateOnlyTransformer implements LineTransformer { @Override public List<String> getResultValues(double... point) { forest.update(point); return Collections.emptyList(); } UpdateOnlyTransformer(RandomCutForest forest); @Override List<String> getResultValues(double... point); @Override List<String> getEmptyResultValue(); @Override List<String> getResultColumnNames(); @Override RandomCutForest getForest();  }### Answer:
@Test public void testGetResultValues() { List<String> result = transformer.getResultValues(1.0, 2.0, 3.0); assertTrue(result.isEmpty()); verify(forest).update(new double[] { 1.0, 2.0, 3.0 }); }