### Question:
CompositeListener implements EventListener { @Override public void startDRGElement(DRGElement element, Arguments arguments) { eventListeners.forEach(el -> el.startDRGElement(element, arguments)); } CompositeListener(EventListener... eventListeners); @Override void startDRGElement(DRGElement element, Arguments arguments); @Override void endDRGElement(DRGElement element, Arguments arguments, Object output, long duration); @Override void startRule(DRGElement element, Rule rule); @Override void matchRule(DRGElement element, Rule rule); @Override void endRule(DRGElement element, Rule rule, Object output); @Override void matchColumn(Rule rule, int columnIndex, Object result);  }### Answer:
@Test public void testStartDRGElement() { listener.startDRGElement(null, null); assertTrue(true); }