Spring LazyInitializationException when using "redirect" in controller - spring-mvc

Question

I started creating an application with Spring-Roo 1.3.1 and Spring-Security 3.1.7
I'm using Spring OpenEntityManagerInViewFilter to be able to do lazy loading of my domain objects.
<filter>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
This is working fine so far. However, I encountered the following issue when doing a redirect from a controller:
#RequestMapping(method = RequestMethod.PUT, produces = "text/html")
public String update(#Valid Service service, BindingResult bindingResult, Model uiModel, HttpServletRequest httpServletRequest) {
if (bindingResult.hasErrors()) {
populateEditForm(uiModel, service);
return "services/update";
}
uiModel.asMap().clear();
serviceRepository.save(service);
return "redirect:/services/" + encodeUrlPathSegment(service.getId().toString(), httpServletRequest);
}
This redirect return "redirect:/services/" + encodeUrlPathSegment(service.getId().toString(), httpServletRequest); is failing with an LazyInitializationException. It fails during execution of the filter chain after the commit is done and redirect took place. The URL redirected to is working when access directly.
When using return "forward:/services/" + encodeUrlPathSegment(service.getId().toString(), httpServletRequest); the page loaded just fine.
I really do not know why the hibernate session is not available when using "redirect". Another strange thing is, when activating DEBUG logging for org.springframework.security.web is is also working fine.
e.g. log4j.logger.org.springframework.security.web=DEBUG
I already searched the internet for some hints but generally lazy loading is working fine in my app, it's just in that circumstance and currently I do not fully understand why.
Any comments/hints are welcome.
Thanks
Stefan

Answer 1

Try to change controller like this:
#RequestMapping(method = RequestMethod.PUT, produces = "text/html")
public String update(#Valid Service service, BindingResult bindingResult,
Model uiModel, HttpServletRequest httpServletRequest) {
if (bindingResult.hasErrors()) {
populateEditForm(uiModel, service);
return "services/update";
}
uiModel.asMap().clear();
Service attached = serviceRepository.save(service);
return "redirect:/services/" +
encodeUrlPathSegment(attached.getId().toString(),
httpServletRequest);
}
The instance service is create by Spring binder to map request values to the object but it is not attached to entityManager (no db session). When you call save you get an attached (instance managed by entityManager) instance so, if you try to get any lazy property from this instance it knows how do it.
You can found more information about JPA objects live cycle here.
Good luck!