Suppose there is a scenario of Users having Tasks. Each User can either be a Watcher or Worker of a Task.
Furthermore, a Worker can file the hours he has worked on a given Task.
Would the following diagram be correct? I have looked around at domain models and I have not seen one with the two associations (works on, watches). Is it acceptable?
EDIT: What about this scenario? An User can make an Offer to another user. A possible way of modelling it is shown on the following diagram.
However, in that diagram it would seem possible for a user to make the offer to himself. Is it possible to model some constraints in, or is this handled further down the development line?
