BackingBean scope

Question

Hello   ADF experts, can you please  clarify my  question.   I have read in some blog   saying  in backingBean scoped bean,  the fields  should be marked as transient.       If the bean  is in  backingBean scope, should we still make the fields  transient ?   BackingBean scoped bean and requestScoped beans need not be seartilized and hence  I do not find any point in making the fields transient !!   Anyway we do not implement Serializable inerface and why is it need to make the fields transient ?
thanks

Answer 1

The Jdev version can make a difference, if you use Jdev 9.0.3. In your case, no, it doesn't make a difference.
Ok, let's think about the problem. A bean in backing bean or request scope will not be serialized so they don't need to implement this interface. On the other side I don't see a disadvantage in doing so nonetheless. If you bind a component to a bean, regardless of the scope, this variable can't be serialized as ui components are not serializable. In a cluster environment this will cause errors. However, if you set the variable to transient the bean can be serialized but after reading it back the info you had is no longer there.
Eugene Fedorenko blogged about this here ADF Practice: Managed Bean Scopes for Component Binding and mentioned a solution available for Jdev versions 11.1.1.4.0.
Summary: I don't see a reason to mark attributes transient. A problem I see doing this is that the bean don't know which scope it's used in. This decision is made when you use the bean in a task flow. Think about what happens if you decide that the bean is used in view score for one task flow. This will crash the application in production under heavy load as the bean would brr serialized empty. From this point of view you should always implement the serializable interface.
Timo