- Creating an event on the necessary object that gets raised whenever an error occurs.
- Creating an errorMessage field/property that's normally null, but gets set any time an error occurs. It's up to the developer to check the field before using the object.
- Similar to 2, except you create an Error object that has properties and such that get set on error.
- Similar to 2 also, create an Enumeration, along the lines of ObjectStatus, that all Business Objects have to indicate the state of the object at all times.
Any other suggestions out there?