This is an extension of the Post/Redirect/Get approach. It ensures that after an operation that updates server-side state, such as a form submission, if the user resubmits the resulting page, the operation is not performed a second time; instead just the results of the operation, reflecting the changed server-side state, is re-rendered.
This has the unwanted requirement that any data needed to render the response must persist between the event request (the form submission) and the render request; this often means that fields must be annotated with @Persist.
|Added in 5.2|
|Added in 5.4|
I specified a zone in my ActionLink/EventLink, so why doesn't my event fire via ajax (request.isXHR() is false)?