@Test
public void should_deserialize_json_to_map() throws Exception {

    String json = "{\"name\": \"walter\", \"lastname\": \"bates\"}";
    Map<String, String> map = objectMapper.fromJsonToMap(json.getBytes(StandardCharsets.UTF_8));
    assertThat(map.get("name")).isEqualTo("walter");
    assertThat(map.get("lastname")).isEqualTo("bates");
}