Correct way of retrieving another bean instance from context

https://stackoverflow.com/questions/4744553

13-10-2019
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Question

We are using the following code to get the managed bean instance from the context.

FacesUtils.getManagedBean("beanName");

Is it the correct way of doing it?. If multiple users access the same bean what will happen? How the bean instances are managed?

Solution

Since FacesUtils is not part of standard JSF implementation, it's unclear what it is actually doing under the covers.

Regardless, when you're already inside a managed bean, then the preferred way is to inject the other bean as managed property. I'll assume that you're already on JSF 2.0, so here's a JSF 2.0 targeted example.

@ManagedBean
@SessionScoped
public void OtherBean {}

@ManagedBean
@RequestScoped
public void YourBean {

    @ManagedProperty("#{otherBean}")
    private void OtherBean;

    @PostConstruct
    public void init() {
        otherBean.doSomething(); // OtherBean is now available in any method.
    }

    public void setOtherBean(OtherBean otherBean) {
        this.otherBean = otherBean;
    }

    // Getter is not necessary.
}

But when you're still on JSF 1.x, then you need to do it by <managed-property> entry in faces-config.xml as explained in this question: Passing data between managed beans.

If you happen to use CDI @Named instead of JSF @ManagedBean, use @Inject instead of @ManagedProperty. For this, a setter method is not required.

Correct way of retrieving another bean instance from context

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