Tukukkk

Before migrating to Spring Boot 2.1.0 I had the following ObjectMapper configured by extending WebMvcConfigurerAdapter working as expected.

@Configuration

public class MvcConfig extends WebMvcConfigurerAdapter {



private static final ObjectMapper objectMapper = buildObjectMapper();



private static ObjectMapper buildObjectMapper() {

    ObjectMapper mapper = new ObjectMapper();

    mapper.setPropertyNamingStrategy(PropertyNamingStrategy.KEBAB_CASE);

    mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);

    mapper.configOverride(LocalDate.class).

            setFormat(JsonFormat.Value.forPattern("yyyy-MM-dd"));

    mapper.registerModule(new JavaTimeModule());

    return mapper;

}



public static ObjectMapper getObjectMapper() {

    return objectMapper;

}



@Override

public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {

    converters.add(new MappingJackson2HttpMessageConverter(objectMapper)); // JSON converter

}

}

However after migrating I can see that setting PropertyNamingStrategy seems to have no effect, my application still expects the format of JSON fields to match the default (e.g. requires "bloodType" instead of "blood-type" as expected).

I don't think that there is any problem with the mapper itself as I use the static getObjectMapper to share the same instance with REST Assured via RestAssuredConfig and seems to be still behaving as expected, if I update my custom mapper to the default behavior (commenting setPropertyNamingStrategy) everything seem to work as expected.

EDIT 1

In fact my whole mapper is being ignored, I tried to change the LocalDate format and it also made no difference. Updating the title to reflect the problem better.

I think your mapper propertyNamingStrategy is not get by spring boot application its getting from hibernate propertyNamingStrategy you should try this.

spring.jpa.hibernate.naming.physical-strategy=com.example.MyPhysicalNamingStrategy

Reference: docs.spring.io/spring-boot/docs/current/reference/html/…

OR:

   @Override

    public void extendMessageConverters(List<HttpMessageConverter<?>> converters) {

        for (HttpMessageConverter<?> converter : converters) {

            if (converter instanceof MappingJackson2HttpMessageConverter) {

                MappingJackson2HttpMessageConverter jsonMessageConverter = (MappingJackson2HttpMessageConverter) converter;

                ObjectMapper objectMapper = jsonMessageConverter.getObjectMapper();

                mapper.setPropertyNamingStrategy(PropertyNamingStrategy.KEBAB_CASE);

                break;

            }

        }

    }

My problem was solved by adding the @EnableWebMvc annotation, which according to the documentation takes complete control of Spring MVC which is not what I wanted originally but at least makes sense. It's not clear for me why it was working before my migration to Spring Boot 2 and why extending the the Spring MVC behavior doesn't work anymore.

I would be grateful for one answer that would add a good explanation for this, and ideally would avoid the full override by @EnableWebMvc.

EDIT 1

Normally you would add @EnableWebMvc for a Spring MVC app, but Spring
Boot adds it automatically when it sees spring-webmvc on the
classpath.

Reference: https://spring.io/guides/gs/serving-web-content/

Unfortunately it's not a complete explanation for me as I can see spring-webmvc:5.1.2.RELEASE in my classpath.

I will mark this as answered considering that using @EnableWebMvc or configuring one @Bean for ObjectMapper are working as expected.

I will would still like to know why the @EnableWebMvc was needed, considering that according to the documentation it shouldn't.