OMG-OCUP2-FOUND100 OMG Certified UML Professional 2 (OCUP 2) - Foundation Level

The diagram shows a UML Sequence Diagram where two messages are being exchanged between lifelines representing instances of

objects: m(C) is being sent from v1 to v2 , and m(D) is being sent back from v2 to v1 .

In a sequence diagram, the vertical order of message arrows shows the sequence of interactions, with time proceeding down the page. Since the message m(C) is shown above m(D) ,

this means that m(C) occurs before m(D) . The receipt of m(C) by v2[B] must therefore occur before v2[B] can send m(D) back to v1[B] .

Therefore, the statement "Receiving m(C) must come before sending m(D) " is always true in this diagram.

B, C, and D are not necessarily true based on the diagram alone: B) "Sending m(D) is the first occurrence of this scenario" is not depicted. C)

"Receiving m(D) is the last occurrence of this scenario" is also not depicted. D) "All occurrences of v[1] will happen before all occurrences of v[3] " is

not something we can infer from this diagram since v[3] is not involved in the interactions shown.

Therefore, the correct answer is:

A. Receiving m(C) must come before sending m(D).

[Reference: Object Management Group (OMG) Unified Modeling Language (UML) Specification Version 2.5.1 Section 17.3 on Sequence Diagrams, which

explains the interpretation of message ordering., ]

Having all the UML diagrams of a model maintain the same level of detail is typically required by tools that automatically transform the model into other forms, such as code or other types of models. Consistency in the level of detail across different diagrams ensures that automated tools can reliably interpret and convert the UML diagrams without encountering discrepancies that could lead to errors or misrepresentations in the generated outputs. This consistency is crucial for maintaining the integrity of the transformations and for ensuring that the resultant products accurately reflect the intended design and specifications.