Spring Boot, Hibernate, Jackson - Lazy serialization

Question

I get in my logs the exception:

Caused by: org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: at....entities.Property.propertyAttribute, could not initialize proxy - no Session

I search and found some proposals. Somehow they didn't help. Seems like the won't fit easily to my current code:

@EnableWebMvc
@Configuration
@ComponentScan("...")
public class WebConfig implements WebMvcConfigurer {

@Bean
    @Primary
    public MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter() {
        final MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        final Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
        converter.setObjectMapper(builder.build());
        return converter;
    }

    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        final Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
        ...
        converters.add(mappingJackson2HttpMessageConverter());

I tried

@Bean
@Primary
public MappingJackson2HttpMessageConverter mappingJackson2HttpMessageConverter() {
    final MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
    final Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();

    final Hibernate5Module module = new Hibernate5Module();
    module.disable(Feature.USE_TRANSIENT_ANNOTATION);
    module.enable(Feature.FORCE_LAZY_LOADING);
    builder.modulesToInstall(module);

    converter.setObjectMapper(builder.build());
    return converter;
}

but this won't fix the error. Any other hints how to solve it?

thx

Do you use spring-boot ? Have you set spring.jpa.open-in-view=true to enable open session in view ? — Alexander Petrov, Mar 30 '20 at 11:37
Please read https://jaxenter.com/jpa-lazy-relations-114468.html — Simon Martinelli, Mar 30 '20 at 11:37
@SimonMartinelli: Yeah, a Join Fetch might help. But this needs a general rewrite :-/ — LeO, Mar 30 '20 at 11:47
Sure. Lazy Loading has to be considered from the beginning. That's a reason why OR-Mapping is a leaky abstraction — Simon Martinelli, Mar 30 '20 at 12:23

Spring Boot, Hibernate, Jackson - Lazy serialization

0 Answers0