### Question:
InstanceIdMixin { @JsonCreator public static InstanceId of(String value) { return InstanceId.of(value); }  @JsonCreator static InstanceId of(String value); @JsonValue abstract String getValue();  }### Answer:
@Test public void verifyDeserialize() throws JSONException, JsonProcessingException { InstanceId id = objectMapper.readValue("\"abc\"", InstanceId.class); assertThat(id).isEqualTo(InstanceId.of("abc")); }
@Test public void verifySerialize() throws IOException { InstanceId id = InstanceId.of("abc"); String result = objectMapper.writeValueAsString(id); assertThat(result).isEqualTo("\"abc\""); }