### Question:
UpdateOnlyTransformer implements LineTransformer { @Override public List<String> getResultColumnNames() { 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 testGetResultColumnNames() { assertTrue(transformer.getResultColumnNames().isEmpty()); }