@Test
public void testNullInternalEventFiltering()
    throws JsonSyntaxException, UnsupportedEncodingException, IOException, OperationException {

  /*
   * Setup mocks for test
   */
  DummyOperation op = spy(new DummyOperation());
  when(op.perform(any(InternalEvent.class))).thenReturn(null);
  DummyOperationFactory operationFactory = new DummyOperationFactory(op);
  OperationProcessor processor = new OperationProcessor(operationFactory);
  /*
   * Do call
   */
  Stream<InternalEvent> stream = processor.perform(Stream.of(new InternalEvent("foo", null, 1)));
  List<InternalEvent> output = stream.collect(Collectors.toList());
  /*
   * Verify nothing came out
   */
  assertEquals(0, output.size());
}