I have a relationship that would greatly benefit from being able to use the <join> clause inside of a component. It appears that this is not available... any reason why?

Just curious.

Think of this: (from section 7.3.2 of 3.2.3 reference manual)


like this:

Hi,
>>> It appears that this is not available... any reason why?
Usage of <many-to-one> ( set, list etc ) is allowed inside components.
So, it is possible to have associated entities.
<join table> is again a means ( and in many cases , the preferred one ) for defining (such) relationships.
Having said that, It looks perfectly valid to support them inside components.
This is my opinion. (Anybody) Please correct me if I am wrong.
I suggest raising a JIRA issue. ( after looking for existing requests, if any )

>>> would greatly benefit from being able to use the <join> clause inside of a component
Here's an alternative.
Check if it helps you.

i) Retain the join table mapping in the parent class.
ii) Use <parent> sub element in <component> to refer back to parent.

<component name="contactInfo" class="ContactInfo">
<parent name="parent" />
....

iii) Access associated entities through getters in component (child) class and delegate all operations to the parent's object.

class ContactInfo {
Person parent ; // with getters and setters
Address getAddress() { return parent.getAddress() ; }
}


Benefits:
At the application level, we access associated entities as if they are elements of component class.

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