[Springframework-rcp-dev] [Spring-JIRA] Commented: (RCP-631) Clearing the valuemodels in AbstractFormModel#setDeliverValueChangeEvents(boolean, boolean) should occur after all ValueChangeEvents are delivered.

[Matthieu S. (JIRA) <no...@sp...>]

    [ https://jira.springsource.org/browse/RCP-631?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=52615#action_52615 ] 

Matthieu Steyt commented on RCP-631:
------------------------------------

Reconsider the example with object X x1 = new X(id=1, A=a1(id=5), B=10) with A another domain object and you set this bean on a formmodel that sets the value of A to an instance a2 with id=5 (fresh from a db back-end) when B=10 (this is necessary for user interaction with the form) and of course a2.equals(a1). But as the value change detector checks on java instance equality (==) instead of using the equals() implementation our formmodel will be dirty after setting x1 on it. I don't think this is desired behaviour. 

One could say, use a value change detector that uses equals(), but:
* does not work with referables/derived valuemodels (when you change a property on the referred entity, you expect the derived value model to change even if oldEntity.equals(newEntity)) 
* a considerable amount of bindings make intensive use of cloning to make a valuemodel clear that something has changed... which will break if you use a value change detector that uses equals()...

> Clearing the valuemodels in AbstractFormModel#setDeliverValueChangeEvents(boolean,boolean) should occur after all ValueChangeEvents are delivered.
> --------------------------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: RCP-631
>                 URL: https://jira.springsource.org/browse/RCP-631
>             Project: Spring Rich Client Project
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 1.1.0
>            Reporter: Matthieu Steyt
>            Assignee: Geoffrey De Smet
>            Priority: Major
>             Fix For: 1.1.1
>
>         Attachments: AbstractFormModelTests.java.patch
>
>
> Consider the following example:
> A formmodel containing two valuemodels A and B. B has a changelistener registered in which A gets a new value. The current implementation of the setDeliverValueChangeEvents(boolean,boolean) method uses the following sequence:
> 1. valueChangeEvents of A are delivered
> 2. A is cleared (dirty = false)
> 3. valueChangeEvents of B are delivered, as a consequence A is adapted (back to dirty)
> 4. B is cleared (dirty = false)
> Result:
> A is dirty, while it is the intention of the method that A is cleared.
> Solution:
> Two for-loops instead of one. One for firing the events and one for clearing the value models.

-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: https://jira.springsource.org/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira