how to change value after controller in spring RESTful - spring

Question

I want change data after #RestController class in Spring
I need to change the fields data based on the specified language.
example:
enum:
public enum Gender {
WOMAN, MAN, OTHER
}
the controller:
#RequestMapping(value = "/get/{id}", method = RequestMethod.GET)
public User get(#PathVariable Long id) throws Exception {
log.debug("Entering get( id={} )", id);
User user = null;
try {
user = UserService.get(id);
} catch (Exception e) {
log.debug("Error occurred in get().", e);
throw e;
}
return user;
}
this output:
{
fisrtName: 'john',
lastName: 'doe',
gender: 'man'
}
change to this output:
{
fisrtName: 'john',
lastName: 'doe',
gender: 'homme'
}

Answer 1

I assume user.gender is a enum. Then you could add a custom Serializer and Deserializer to your JSON Mapper (hopefully Jackson).
#JsonComponent
public class TranslatedGenderJsonComponent {
public static class TranslatedGenderSerializer extends StdSerializer<Gender> {
public TranslatedGenderSerializer () {
super(Gender.class);
}
public void serialize(
Gender gender, JsonGenerator generator, SerializerProvider provider)
throws IOException, JsonProcessingException {
String translatedGender = myTranslateFunction(gender);
generator.writeString(translatedGender );
}
}
public static class TranslatedGenderDeserializer extends StdDeserializer<Gender> {
public TranslatedGenderDeserializer () {
super(Gender.class);
}
public Gender deserialize(JsonParser jp, DeserializationContext ctxt)
throws IOException, JsonProcessingException {
JsonToken currentToken = jp.getCurrentToken();
if (currentToken.equals(JsonToken.VALUE_STRING)) {
String text jp.getText().trim();
Gender gender = myInverseTranslateFunction(text);
return gender;
} else if (currentToken.equals(JsonToken.VALUE_NULL)) {
return getNullValue();
} else {
throw ctxt.mappingException(Gender.class);
}
}
}
}
This code is not tested, it is just written in the browser! (I am quite unsure with the deserializer/parser code.) But I hope it will guide you to a solution.

Answer 2

I changed code:
the controller:
#Autowired
GlobalMassengerAdvice globalMassenger;
#RequestMapping(value = "/get/{id}", method = RequestMethod.GET)
public User get(#PathVariable Long id) throws Exception {
log.debug("Entering get( id={} )", id);
User user = null;
try {
user = userService.get(id);
String value = globalMassenger.getMessage(user.getGender().name());
user.setGender( value );
} catch (Exception e) {
log.debug("Error occurred in get().", e);
throw e;
}
return user;
}
I add new Class (GlobalMassengerAdvice):
#ControllerAdvice
public class GlobalMassengerAdvice {
#Autowired
private MessageSource messageSource;
public String getMessage(final String messageKey, final Object... messageParameters) {
Locale locale = LocaleContextHolder.getLocale();
String result = null;
try {
result = messageSource.getMessage(messageKey, messageParameters, locale);
} catch (NoSuchMessageException e) {
result = messageKey;
}
return result;
}
}