### Question:
ChatRepository { public void requestSendMessage(int groupId, String message) { encoder.sendChatMessage(groupId, message); } ChatRepository(ChatDao chatDao, RequestEncoder encoder,
                          Handler backgroundHandler); void addMessage(ChatMessage message); LiveData<PagedList<ChatMessage>> getMessagesByGroupId(int groupId); void requestSendMessage(int groupId, String message); void deleteAllMessages();  }### Answer:
@Test public void requestMessageTest() { testChatRepository.requestSendMessage(mockGroupId, mockMessageContent); verify(mockEncoder).sendChatMessage(mockGroupId, mockMessageContent); }