Configure a Jackson's DeserializationProblemHandler in Spring environment [duplicate]

Answer 1

It's not possible to directly add a DeserializationProblemHandler to the ObjectMapper via a Jackson2ObjectMapperBuilder or Jackson2ObjectMapperBuilderCustomizer. The handlerInstanciator() method is for something else.

However, it's possible to do so by registering a Jackson module:

• the builder has a modules() method
• the module has access via setupModule() to a SetupContext instance, which has a addDeserializationProblemHandler() method

This works:

@Bean
public Jackson2ObjectMapperBuilderCustomizer customizer() {
    return new Jackson2ObjectMapperBuilderCustomizer() {
        @Override
        public void customize(Jackson2ObjectMapperBuilder builder) {
            builder.modules(new MyModule());
        }
    };
}

private static class MyModule extends SimpleModule {
    @Override
    public void setupModule(SetupContext context) {
        // Required, as documented in the Javadoc of SimpleModule
        super.setupModule(context);
        context.addDeserializationProblemHandler(new NullableFieldsDeserializationProblemHandler());
    } 
}

Answer 2

What about writing a bean like this:

@Configuration
public class ObjectMapperConfiguration {

    @Bean
    ObjectMapper objectMapper() {
        ObjectMapper objectMapper = new ObjectMapper();
        // jackson 1.9 and before
        objectMapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false); 
        // or jackson 2.0
        objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
        return objectMapper;
    }
}

This is for global configuration. If, instead, what you want to do is to configure the feature for specific a class, use this annotation above the class definition:

@JsonIgnoreProperties(ignoreUnknown = true)