How can I register and use the jackson AfterburnerModule in Spring Boot?

Question

I am using SpringBoot 1.5.9., Jackson 2.8 and Spring Framework 4.3.13.

I am trying to register and use the AfterburnerModel.

According to the Spring Boot documentation, to configure the ObjectMapper you can either define the bean yourself and annotate it with @Bean and @Primary. In the bean you can register a module. Or you can add a bean of type Jackson2ObjectMapperBuilder where you can customize the ObjectMapper, by adding a module.

I have tried both ways, and during serialization none of my breakpoints in jackson-module-afterburner fire. My customizations are being read, but seem to be being ignored.

Solution

By default Spring MVC MappingJackson2HttpMessageConverter will create its own ObjectMapper with default options using Jackson2ObjectMapperBuilder. As per Spring Boot docs 76.3 Customize the Jackson ObjectMapper chapter:

Any beans of type com.fasterxml.jackson.databind.Module are automatically registered with the auto-configured Jackson2ObjectMapperBuilder and are applied to any ObjectMapper instances that it creates. This provides a global mechanism for contributing custom modules when you add new features to your application.

so it should be enough to register your module as a bean:

@Bean
public AfterburnerModule afterburnerModule() {
  return new AfterburnerModule();
}

A more detailed setup can be achieved with @Configuration class to customize the MappingJackson2HttpMessageConverter:

@Configuration
public class MyMvcConf extends WebMvcConfigurationSupport {

  protected void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
    converters.add(myConverter());
    addDefaultHttpMessageConverters(converters);
  }

  @Bean
  public MappingJackson2HttpMessageConverter myConverter() {
    return new MappingJackson2HttpMessageConverter(myObjectMapper())
  }

  @Bean
  public ObjectMapper myObjectMapper() {
    return new ObjectMapper().registerModule(new AfterburnerModule());
  }

}

Comments

[dasPing]

Thanks, I already tried that. As I mentioned in the original post the bean is being read. The problem I suspect is that other ObjectMappers are being created and used for example by AllEncompassingFormHttpMessageConverter

[Karol Dowbecki]

Updated the answer, most likely your new ObjectMapper is not configured as part of the Spring MVC converters.

[dasPing]

Interesting, but the same problem. Here is the current stacktrace where the defualt objectmapper is being created: ObjectMapper.<init>() line: JsonMapperConfigurator.getDefaultMapper() ResteasyJackson2Provider(ProviderBase).locateMapper(Class<?>‌​, MediaType)

[Karol Dowbecki]

You seem to be using JAX-RS with RESTEasy which is not mentioned in your question. Check stackoverflow.com/a/29019303/1602555.

[Josh C.]

Do you notice a performance improvement after adding afterburner? Do you know if this works with spring kafka's jsonserializer?