### Question:
EventFilter implements EventSink { protected void forward(BusData data) throws IOException { Ensure.not_null(data); EventSink sink; synchronized (this) { sink = m_sink; } if (sink != null) { sink.sink(data); } } EventFilter(); synchronized void connect(EventSink s); synchronized EventSink connected(); EventFilterInfo info(); synchronized void lock(Object l); synchronized void unlock(Object l); synchronized boolean locked();  }### Answer:
@Test(expected = AssertionError.class) public void event_filter_forward_null() throws Exception { m_filter.forward(null); }