[TAP5-158] @Persist("redirection")

• Type: New Feature
• Status: Resolved
• Priority: Minor
• Resolution: Abandoned
• Affects Version/s: 5.0.15
• Assignee: Howard Lewis Ship
• Reporter: Geoff Callender
• Created: 08/Feb/08 09:43
• Updated: 23/Nov/11 19:06
• Resolved: 23/Nov/11 19:06

Description

Suggesting a new persistence strategy, @Persist("redirection"), which is a fine-tuning of "flash" to a specific, very common, requirement. It would be semantically clearer and less prone to errors than using "flash".

It's common to want persistence of an object during the redirection portion of an action request, and not between render requests. Using "flash" it's common to do this:

@Persist("flash")
private Person _person;

void onActivate(Long id) throws Exception {
_personId = id;
if (_person == null)

{ _person = getPersonService().findPerson(_personId); }

}

However, it has a problem - every 2nd time you reload/refresh the page (which is a render request), _person will not be refreshed because every 2nd time it won't be null. This is disconcerting and pretty much incorrect behaviour.

A solution is to nullify _person in cleanupRender(). But if we do that then we're not really using "flash" any more. It may as well be "session". And it's easy to forget to nullify _person, and it's less obvious to the reader. So..... how about @Persist("redirection") whose intention is absolutely clear and will work correctly without the programmer adding to cleanupRender()?

To be extra-clever, an enhancement may be to persist it with a temporary conversation-id behind the scenes, making it absolutely impossible for two windows in the same session to accidentally collide on it during concurrent redirections.