[hibernate-dev] Group sequence adjustments

[Hardy Ferentschik]

Some comments on groups

On Fri, 20 Feb 2009 15:40:21 +0100, Emmanuel Bernard  
<emmanuel at hibernate.org> wrote:

> To implement such ordering, a group can be defined as a sequence of
> other groups. Each group in a group sequence must be processed
> sequentially in the order defined by at GroupSequence.value when the
> group defined as a sequence is requested. Note that a group member of
> a sequence can itself be composed of several groups via inheritance or
> sequence definition. In this case, each composed group must respect
> the sequence order as well.

An example would be good here. Showing the exact execution order in the  
case of
group sequence containing say three groups whereof say two have  
superinterfaces.


> Groups defining a sequence and groups composing a sequence must not be
> involved in a cyclic dependency either directly or indirectly, either
> through cascaded sequence definition or group inheritance.
>
> Groups defining a sequence should not directly inherit other groups.
> In other words, the interface hosting the group sequence should not
> have any super interface.
>
> Groups defining a sequence should not be used directly in constraint
> declarations. In other words, the interface hosting the group sequence
> should not be used in a constraint declaration.

What does "must not" and "should not" mean in these paragraphs? Should a
ValidationException be thrown? Is it up to the provider?

--Hardy