Getting java.io.NotSerializableException with a spring service when stopping tomcat

Question

i am using spring 3 with JSF 2 and i replaced JSF managed beans with spring beans, by adding on top of bean:

@Component(\"mybean\")
@Scope(\"session\")


        

Answer 1

Well, finally i was able to make it work fine as follows:

1- The Service:

@Service
@Scope("singleton")
public class PersonService{

}

2- The Spring Managed Bean:

 @Component("person")
   @Scope("session")
   public class PersonBean implements Serializable{

   @Inject
   private PersonService personService;

   }

waiting for your feedback.

Answer 2

Looking at the error, It looks like tomcat is trying to serialize the entire spring context, I think it might be due to the fact that your are implementing Serializable on Service. I was thinking may be you need to do this, I don't know JSF that well but my understanding of scoped beans makes me think, You might need some thing like this

    @Component
    @Scope(proxyMode=ScopedProxyMode.TARGET_CLASS, value="session")
    public class MyBean implements Serializable
    {
       //no need to implement serializable on service
       @Autowired(required=true)
       private MyService service;
    }

Answer 3

You get this exception because the class does not implement Serializable. Tomcat serializes currently running HttpSession objects including all its attributes to disk whenever it is about to restart/redeploy, so that they are revived after the cycle. Session scoped objects are stored as attributes of the HttpSession, hence they need to implement Serializable to survive the restart/redeploy as well.

If you would like to make them Serializable, then implement it accordingly:

public class YourSpringService implements Serializable {}

Otherwise, just ignore the exception or turn off serializing sessions to disk in Tomcat's config.

Note that the same story also applies to JSF view/session scoped beans.

Answer 4

I had to use readObject() + static ApplicationContext hack to solve the issue:

@Component
@Scope(value = SCOPE_SESSION, proxyMode = ScopedProxyMode.TARGET_CLASS)
public class FlashMessages implements Serializable {    

    @Autowired
    transient private SomeBean someBean;

    private void readObject(ObjectInputStream ois) throws ClassNotFoundException, IOException {
        ois.defaultReadObject();
        // restore someBean field on deserialization
        SpringUtils.getContext().getAutowireCapableBeanFactory().autowireBean(this);
    }

}

@Component
public class SpringUtils implements ApplicationContextAware {

    static ApplicationContext applicationContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        SpringUtils.applicationContext = applicationContext;
    }

    public static ApplicationContext getContext() {
        return applicationContext;
    }

}