### Question:
EventGroup { public void clearEvents() { this.events.clear(); } EventGroup();  EventGroup(List<Event> events);  EventGroup(Set<Event> events);  EventGroup(Event... events); Set<Event> getEvents(); void addEvents(Event... events); void clearEvents(); Event getMainEvent(); @Override String toString();  }### Answer:
@Test public void testClearEvents() { assertTrue(this.g.getEvents().isEmpty()); this.g.addEvents(this.event1); this.g.addEvents(this.event2); this.g.addEvents(this.event3); assertFalse(this.g.getEvents().isEmpty()); this.g.clearEvents(); assertTrue(this.g.getEvents().isEmpty()); this.g.clearEvents(); assertTrue(this.g.getEvents().isEmpty()); this.g.addEvents(this.event1); assertFalse(this.g.getEvents().isEmpty()); this.g.clearEvents(); assertTrue(this.g.getEvents().isEmpty()); }