@Test
  public void sendEventShouldNotFailWhenObjectMapperThrowsException() throws Exception {
    doThrow(new JsonGenerationException("Nothing serious!")).when(mapper).writeValueAsString(any());
    Event event = mock(Event.class);

    eventSinkImpl.queueEvent(event);
    verify(mockClientProducer, never()).send(any(ClientMessage.class));
  }
 @Test
 public void sendEventShouldSendMessageOnProperEventInput() throws Exception {
   final String content = "Simple String";
   doReturn(content).when(mapper).writeValueAsString(anyObject());
   ArgumentCaptor<ClientMessage> argumentCaptor = ArgumentCaptor.forClass(ClientMessage.class);
   eventSinkImpl.queueEvent(mock(Event.class));
   eventSinkImpl.sendEvents();
   verify(mockClientProducer).send(argumentCaptor.capture());
   assertEquals(content, argumentCaptor.getValue().getBodyBuffer().readString());
 }