Redirecting JSF Requests in the Correct Manner

C.

When handling a JSF request, your application code has the ability to redirect the call to another URL by using an HTTP redirect. However, when performing this redirection, it is important to ensure that the JSF lifecycle is properly completed to avoid any potential issues.

In order to correctly complete the handling of the JSF lifecycle after performing an HTTP redirect, the correct action to take is to invoke the responseComplete() method on the FacesContext object. This method signals to the JSF implementation that the response has been sent to the client and the lifecycle should be terminated immediately.

Option A, setting the immediate="true" attribute on the command button used to perform the call, has a different purpose. The immediate attribute indicates that the component should be processed during the Apply Request Values phase of the lifecycle, bypassing the Process Validations and Update Model Values phases. This attribute is typically used for components that perform actions that should not affect the model data, such as cancel buttons.

Option B, invoking the dispatch() method on the ExternalContext object, is used to forward a request to another resource within the same web application. This method does not perform an HTTP redirect and does not terminate the JSF lifecycle. Instead, it delegates control to the target resource, allowing it to complete its own lifecycle.

Option C, invoking the setCurrentPhaseId(RENDER_RESPONSE) method on the FacesContext object, sets the current phase of the lifecycle to the RENDER_RESPONSE phase. This method should only be used in rare cases when it is necessary to skip phases of the lifecycle, such as when implementing custom components.

In summary, when performing an HTTP redirect in a JSF application, the correct action to complete the lifecycle is to invoke the responseComplete() method on the FacesContext object.