Using derived property to calculate weight

[yonedal]

Suppose I have the following blocks:

dp1.PNG

What I want:
When I make an instance of this, I want total weight to be the sum of all of the weight values from the Sub-Blocks.

As I understand, I have to make a Customization Element whose target I set as a stereotype, and I apply that stereotype to Main Block, and then I have an OCL expression to calculate the value of the block (though I thought OCL just returned Boolean values?) which then has to have either a Java Listener put together or a Metachain.

I'm struggling to figure out what goes where to do this, so if someone could just provide a basic example that does what I'm after it would be greatly appreciated.

[ieva.n]

Hello,

Have you looked into using Rollup Pattern? http://docs.nomagic.com/display/SYSMLP1 ... ern+Wizard

Sincerely,
No Magic, Inc. Customer Support

[yonedal]

I have not. I will look into that. Thanks!

[yonedal]

OK, so I went through the RollUp example and, instead of using that, tried just using constraints and a parametric diagram to get what I want.

However, at the instance level the value is not being updated.

I've attached the model I'm experimenting in to this post (see under the Package Simple Addition).

Referencing the attached image, what I want to happen is for the slot totalWeight the be filled with the value (in this instance) 12.2. So what am I missing in making that happen?

dp2.PNG

Edit:
I am using Cameo Enterprise Architecture 18.4.

[marthaaustin1977@gmail.com]

I could not even imagine that I would be interested in this topic. But in fact it is very interesting and exciting.