CODEWITHSUNDEEP
javaspring-bootjackson
Amit Kumar Gupta
Amit Kumar Gupta

Reputation: 7413

Spring Boot Jackson mappings are not working

I am using fasterxml jackson for json serialization. I have written date serializer as 

public class DateObjectSerializer extends JsonSerializer<Date> {
    public static final String DATE_FORMAT = "dd.MM.yyyy";

    @Override
    public void serialize(Date date, JsonGenerator jgen, SerializerProvider provider) throws IOException, JsonProcessingException {
        System.out.println("From DateObjectSerializer");
        SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_FORMAT);
        String formattedDate = dateFormat.format(date);
        jgen.writeString(formattedDate);
    }
}

But it is not being invoked. However other Jackson Serializers are working fine.

So I added following configuration in application.yaml

spring:
  jackson:
    serialization-inclusion: non_null
    date-format: dd.MM.yyyy

But it din't work.

So I have added this code in SpringBootConfiguration class.

@Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
    final MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
    final ObjectMapper objectMapper = new ObjectMapper();
    SimpleDateFormat dateFormat = new SimpleDateFormat(DATE_FORMAT);
    objectMapper.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false).setDateFormat(dateFormat);
    converter.setObjectMapper(objectMapper);
    converters.add(converter);
    super.configureMessageConverters(converters);
}

Now dates are being serialized correctly. But now valid JSON equivalent strings are not being transformed to JSON as mentioned here.

@RestController
public class SampleController {

    @RequestMapping(value = "/jsonInfo", method = RequestMethod.GET, produces = APPLICATION_JSON_VALUE)
    public String jsonInfo() {
        String string = "{\"name\": \"foo\"}"
                return string;
    }
}

Upvotes: 1

Views: 3356

Answers (1)

Abhijeet Patil
Abhijeet Patil

Reputation: 314

Try this

import com.fasterxml.jackson.databind.ObjectMapper;

:

@Autowired
private ObjectMapper objectMapper;

@RestController
public class SampleController {

    @RequestMapping(value = "/jsonInfo", method = RequestMethod.GET, produces = APPLICATION_JSON_VALUE)
    public JsonNode jsonInfo()  throws JsonProcessingException, IOException {
        String string = "{\"name\": \"foo\"}"
                return objectMapper.readTree(string);
    }
}

Upvotes: 2

Related Questions