@Test
    public void loadJsonFromFile() throws Exception {
        DataModel mockResult = jsonMockUtility.getJsonToMock(
                "data.json",
                DataModel.class);

        when(mockContext.getAssets().open(anyString())).thenReturn(mockInputStream);
        when(jsonUtil.getJsonFromFile(mockContext, "", DataModel.class)).thenReturn(mockResult);
        presenter.loadJsonFromFile(mockContext);
    }