[Error] Type definition error: [simple type, class org.hibernate.proxy.pojo.bytebuddy.ByteBuddyInterceptor]

이 에러 메시지를 만난 것은 권장하지 않는 방식으로 데이터를 조회하고 있을 가능성이 크다.

즉, 엔티티를 직접 노출하고 있는 것인데 해당 방식이 아닌 DTO에 담아서 조회하도록 수정하는 것이 좋다.

 

해당 에러가 발생하는 이유는 JPA 사용시 OneToOne 또는 ManyToOne 관계에서 LAZY로 걸려있기 때문에 프록시 객체를 가져와서 사용하게 되는데 JSON이 루프를 돌려서 데이터를 가져오려고 할 때 프록시이기 때문에 가져올 수 없어서 발생하는 에러이다.

 

에러 메시지

"error": "Internal Server Error",
"trace": "org.springframework.http.converter.HttpMessageConversionException: Type definition error: [simple type, class org.hibernate.proxy.pojo.bytebuddy.ByteBuddyInterceptor]\n\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.writeInternal(AbstractJackson2HttpMessageConverter.java:489)\n\tat org.springframework.http.converter.AbstractGenericHttpMessageConverter.write(AbstractGenericHttpMessageConverter.java:114)\n\tat org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:297)\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:192)\n\tat org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:78)\n\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:136)\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:926)\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:831)\n\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)\n\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1089)\n\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:979)\n\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014)\n\tat org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:903)\n\tat jakarta.servlet.http.HttpServlet.service(HttpServlet.java:564)\n\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885)\n\tat jakarta.servlet.http.HttpServlet.service(HttpServlet.java:658)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:195)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140)\n\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140)\n\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140)\n\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140)\n\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140)\n\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:167)\n\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90)\n\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:483)\n\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:115)\n\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93)\n\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74)\n\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344)\n\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:384)\n\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63)\n\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:904)\n\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1741)\n\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52)\n\tat org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1190)\n\tat org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)\n\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:63)\n\tat java.base/java.lang.Thread.run(Thread.java:833)\nCaused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: No serializer found for class org.hibernate.proxy.pojo.bytebuddy.ByteBuddyInterceptor and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: java.util.ArrayList[0]->jpabook.jpashop.domain.Order[\"member\"]->jpabook.jpashop.domain.Member$HibernateProxy$iivJcOPp[\"hibernateLazyInitializer\"])\n\tat com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:77)\n\tat com.fasterxml.jackson.databind.SerializerProvider.reportBadDefinition(SerializerProvider.java:1330)\n\tat com.fasterxml.jackson.databind.DatabindContext.reportBadDefinition(DatabindContext.java:414)\n\tat com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.failForEmpty(UnknownSerializer.java:53)\n\tat com.fasterxml.jackson.databind.ser.impl.UnknownSerializer.serialize(UnknownSerializer.java:30)\n\tat com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732)\n\tat com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770)\n\tat com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183)\n\tat com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:732)\n\tat com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:770)\n\tat com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:183)\n\tat com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serializeContents(CollectionSerializer.java:145)\n\tat com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:107)\n\tat com.fasterxml.jackson.databind.ser.std.CollectionSerializer.serialize(CollectionSerializer.java:25)\n\tat com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:502)\n\tat com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:422)\n\tat com.fasterxml.jackson.databind.ObjectWriter$Prefetch.serialize(ObjectWriter.java:1570)\n\tat com.fasterxml.jackson.databind.ObjectWriter.writeValue(ObjectWriter.java:1061)\n\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.writeInternal(AbstractJackson2HttpMessageConverter.java:483)\n\t... 48 more\n",
"message": "Type definition error: [simple type, class org.hibernate.proxy.pojo.bytebuddy.ByteBuddyInterceptor]",
"path": "/api/v1/simple-orders"

 

이 문제를 해결하려면 HibernateModule을 사용해야 한다.

 

스프링 부트 3.0 미만은 Hibernate5Module을 등록해야 한다.

build.gradle 에 다음 라이브러리를 추가 후

implementation 'com.fasterxml.jackson.datatype:jackson-datatype-hibernate5'

 

XXXXApplication 에 다음 코드를 추가하자

@Bean
Hibernate5Module hibernate5Module() {
	return new Hibernate5Module();
}

 

스프링 부트 3.0 이상은 Hibernate5JakartaModule 등록해야 한다.

build.gradle에 다음 라이브러리를 추가 후

implementation 'com.fasterxml.jackson.datatype:jackson-datatype-hibernate5-jakarta'

 

XXXXApplication에 다음 코드를 추가하자

@Bean
Hibernate5JakartaModule hibernate5Module() {
	return new Hibernate5JakartaModule();
}

 

기본적으로 초기화 된 프록시 객체만 노출, 초기화 되지 않은 프록시 객체는 노출 안함