Release date: Monday, 09.12.13 - Due date: Sunday, 15.12.13, 23:59

a) Describe in your own words, with at least a sentence for each, the meta levels M0, M1, M2 and M3. If it helps you in your explanation, you can also give a concrete example (another than the one in b)) and explain it.

b) This lecture is named “Advanced Topics in Software Construction 2013” and has the identification number “13ws-12475” (or “MA-INF 3212” if you are a Computer Science student). Use this information as starting point (M0) and derive M1 from it with the help of a UML class diagram. After you have created M1, how do M2 and M3 look like?

[Taken with minor modifications from the exam 2012.]

Figure 1: The voyage of five barrels of single malt whiskey from Edinburgh to its twin city Munich	Figure 2: Transportation Diagram showing the same voyage

Some domains have their own graphical modeling languages. The MOF-approach allows us to implement these modeling languages. This task gives an example. You will have to fill in some gaps.

The transport of goods e.g. from Edinburgh in Scotland to Munich in Germany (Figure 1) can be visualized in a Transportation Diagram (Figure 2). Such a diagram¹⁾ consists of one row for each vehicle and another row for the ground level, the ports. Voyages are visualized as lines within a row. These lines are connected by arrows visualizing the process of loading and unloading goods. A suggestion for the abstract syntax of Transportation Diagrams is given as a metamodel (Figure 3). An instance of this metamodel represents an instance of a Transportation Diagram (Figure 4 represents Figure 2 in abstract syntax).

Figure 2 models the transport visualized in Figure 1. Figure 4 represents the model Figure 2 and is an instance of Figure 3. Your task is to complete the figures:

a) Complete the Transportation Diagram (Figure 2) so that it models as well how the goods reach Munich from Hamburg. You can find the figure as an image in the astah file.

b) Complete the Meta Model (Figure 3) so that it represents all elements of the Transportation Diagram. You need to add two classes and add their associations with navigability, multiplicities (if not “1..1”) and maybe composition ends.

Figure 3: Metamodel of Transportation Diagrams	Figure 4: The Transportation Diagram instance in abstract syntax

c) To which metalevel does Figure 2 belong? Why?

d) To which metalevel does Figure 3 belong? Why?

e) To which metalevel does the Meta-Object Facility (MOF) belong? How does Figure 3 relate to the MOF?

f) Complete the representation of the Transportation Diagram in abstract syntax (Figure 4). You need to add two instance specifications with their attribute values and all their links.

g) Why did we work with MOF here and did not just create a UML profile? What are the advantages/disadvantages of the MOF-based approach?

[Taken with minor modifications from the exam 2012.]

a) Define a UML profile that allows to create Analysis Object Models with use case slices. For that purpose we need the stereotypes: «use case slice», «non-use case specific slice», «extend», «include», «use», «aspect». As a starting point you find some of the metaclasses of the UML.

Don't let the complex model below scare you. If you know how profiles are defined, the task is straightforward!

Excerpt of the UML Meta-Model

b) To which metalevel does the profile belong? Why?

c) UML Profiles vs. MOF-based meta-models: What are the general advantages/disadvantages of UML profiles compared to Ecore/MOF-based meta-models?

d) Explain how one can see in the class diagram you created, that we may draw a class within an «aspect»?

e) Explain how one can see in the class diagram above, that «extend» may connect e.g. «use case slice»?

f) (optional) Describe in OCL the condition, that dependencies with the stereotype «extend» may only connect packages with the stereotype «use case slice» or «non-use case specific slice».²⁾

In the lecture we suggested that there is an analogy between the meta levels of UML and meta levels for regular expressions.

Given the following grammar for regular expressions in Backus-Naur Form:

<RE> ::= <Terminal> | <RE><RE> | <RE>"|"<RE> | <RE>"*" | "("<RE>")"

a.) What is the corresponding level for this grammar? Explain your decision.

b.) Are there levels above and below? Name them all and give for each an example.

c.) In UML the top level conforms to itself, what is the equivalent for the Backus-Naur Form?