Why is this ATL helper wrong?

Question

I'm new to ATL and OCL and I'm trying to transform this metamodel: enter image description here

into this one: enter image description here

The helper is meant to take all the tests created by the user admin and after that sum the id's of the Actions of that test.
I've done this helper:

helper def: actionsId: Integer = Test!Test.allInstances()->select(i | i.md.user='admin')->collect(n | n.act.id.toInteger())->sum();

But when I run the transformation I'm having this error:

org.eclipse.m2m.atl.engine.emfvm.VMException: Collections do not have properties, use ->collect()

This error is in the collect(n | n.act.id.toInteger()) part of the helper.

The rest of my code is this:

rule Testset2Testcase{
    from s: Test!Test
    to r: Testcase!Testcase(
        ident <- thisModule.actionId.toString(),
        date <- s.md.date,
        act <- thisModule.resolveTemp(s.act,'a')
    )
    do{
        'Bukatuta'.println();   
    }
}

rule Action2Activity{
    from s: Test!Action
    to a: Testcase!Activity(
        ident <- s.id   
    )
}

Sorry for my bad english.

I've read it now, sorry I thought it was about the ATL transformation language. I'll change it. — Mikel Molinuevo

Mikel Molinuevo Mikel Molinuevo · Accepted Answer · 2018-05-21T13:58:34

My teacher helped me with this.
The problem was in the helper.
Doing this:

helper def: actionsId: Integer = Test!Test.allInstances()->select(i | i.md.user='admin')->collect(n | n.act.id.toInteger())->sum();

I was trying to take the id of a collection of collections of the type Action instead of taking the id of each objects.

With that helper I was taking a collection of collections so using flattener this collection of collections became a collection of Actions.

The helper written in a correct way looks like this:

helper def: actionsId: Integer = Test!Test.allInstances()->select(i | i.md.user='admin')->collect(n | n.act)->flatten()->collect(x | x.id.toInteger())->sum();

Why is this ATL helper wrong?

2 Answers