如何重置Spring托管Bean

Question

NOTE: This issue may or may not be Vaadin related, depending on wether there is a "better" solution to "resetting" the bean or not.

Background scenario

I am building a wizard for entering some values that, when finished, is sent to a table (using Vaadin and the add-on "Wizards for Vaadin").

The add-on does not provide a way to reset the Wizard (ie go back to step 1) without a forced call to the current steps (overridden) onAdvance() and onBack() methods, which will return false in some of my steps because I'm using logic in those methods in case the use for example haven't filled in all required data.

I cannot simple create a new instance of the Wizard, because I'm using Spring to manage this @Component.

So, this leaves me with actually resetting the bean in order to reset the wizard correctly.

My question is

How do I "reset" a Spring managed Bean (@Component)? I should add that this Bean also has some dependencies injected to it.

or... (for the Vaadin people):

Is there another way of resetting this wizard other than creating a new Wizard?

Some code

@Component
@Scope("session")
public class MyWizard extends Wizard {

    @Inject
    private MyWizardContainer myWizardContainer;
    @Inject
    private MyService myService;
    @Inject
    private MyWizardStep1 myWizardStep1;
    @Inject
    private MyWizardStep2 myWizardStep2;
    @Inject
    private MyWizardStep3 myWizardStep3;
    @Inject
    private MyMainTableContainer myMainTableContainer;

    final static Logger logger = LoggerFactory.getLogger(MyWizard.class);

    private static final long serialVersionUID = 1L;

    public MyWizard() {
        setupListener();
    }

    public void addSteps() {
        this.addStep(myWizardStep1);
        this.addStep(myWizardStep2);
        this.addStep(myWizardStep3);
        this.mainLayout.setComponentAlignment(this.footer, Alignment.BOTTOM_LEFT);
    }

    private void setupListener() {

        this.addListener(new WizardProgressListener() {

            @Override
            public void wizardCompleted(WizardCompletedEvent event) {
                endWizard("Wizard Finished Successfully!");
            }

            @Override
            public void wizardCancelled(WizardCancelledEvent event) {
                endWizard("Wizard Cancelled!");
            }

            @Override
            public void stepSetChanged(WizardStepSetChangedEvent event) {
                // TODO Auto-generated method stub
            }

            @Override
            public void activeStepChanged(WizardStepActivationEvent event) {
                // TODO Auto-generated method stub
            }
        });
    }

    private void resetWizard() {
        myWizardContainer.removeAll(); //here I'm simply resetting all data that the user generated thus far in the wizard
        this.activateStep(myWizardStep1); //this will not work, as some steps will not always return true on onBack() and/or onAdvance()
    }

    private void endWizard(String message) {
        resetWizard();
        this.setVisible(false);
        Notification.show(message);
    }
}

Answer 1

SpringVaadinIntegration, that you probably use, does not require all elements to be @Components, only UI has to be annotated.

Your wizard and it's steps should not be components in this case, if you really need to inject dependencies into them you can use @Configurable annotation, which allowes to inject dependencies to classes not managed by Spring (some more configuration needed to make it work). Just create wizard and steps as new objects when you need them.