actifsource

Hi,

I want to create several types of java objects, so I wrote a simple Entity-Attribute-Relation model. Now I wanted to specialize a bit, i.e. creating a subclass of Entity that already has 4 relations to 4 Attributes. Can such be achieved? Or are there better ways to do the same? The reason I like to make the relations is that the code is then generated similarly to the other specialized objects.

My case (simplified)

Entity -> Attributes
^
FooEntity

I want the FooEntity to contain 4 relations to attributes, i.e. dateCreated, dateMofified. These should be relations to Attributes. I know I can code them in a template, but then I can't use the nice code-generation capalibities

Hi Rob

Thank you for your interesting question. I would suggest that you model an extends relationship between the entities:



Doing so allows you to model the base entities with the desired attributes:



Writing standard template code you would ask for all attributes in the entity as follows:



This would lead to the following result:



But it is also possible to write much more complex selector expressions which are able to recursively call themselves.

• Create a new resource of type FunctionSpace
• Inside, create a new ResourceInfo with typeRef Entity
• Inside create a new SelectorFunction named allEntity
• returnType shall be of type ListType with innerTypeRef Entity

This means that we create a function which can be called in the template on type Entity and returns a list of Entity. The idea is now to collect all base entities which can be recursively reached via the extends relation.

For that reason please enter the following selector statement:

• Entity.extends.allEntity@Common union Entity:Entity

This means that

• On the current entity we follow the extends relation an call ourself recursively
• Then we create a union (set theory) with the current entity itself

As a result, you are now able to use allEntity in your template code and ask for the attributes on this result:



As a result the generated files contains all the entity from the modeled base classes:



Please find the working example for actifsource V 5.3.2 here:

Thanks, very nice read!

I will definately try it