A Second Comprehensive Application Example - Model-Driven and Software Product Line Engineering - page 189

always has a main element that groups other elements.
For example, in a music store application, it should be
a MusicStore Group that assembles Discs and every Disc
assembles Songs . Every element in the collection has a set of
properties, and these properties are possibly related to other
elements of the collection. Finally, each element is responsible
for making its information persistent. Some of the functions
that collection manager systems must provide include:
- Create, Remove, Update, and Delete Elements. These are
generic facilities to manage elements in collections.
- Organize, Filter, and Serialize Elements. Elements in a
collection must be organized according to several criteria to
be presented to final users, for instance, alphabetical ordering
of names, price ordering, etc. They can also be filtered for
presentation to users or exported in several kinds of files.
- Graphic Presentation of Elements. Elements must be
presented in different presentation views, such as tree, list,
graph, or table.
Theseareonlysomesamplefunctionalitiesconsideredinthe
second example. In this example, however, we could consider
several other sources of variation, for example, performance
issues of data management (memory and time consumption).
Here, we simplify the problem and consider two dimensions:
the kernel functionality, which allows us to vary the business
domain (scholar, music store, or any kind of store, employees
in a company, etc.) and the graphic presentation. Thus, we can
deal with the usual range of classic variations we find in any
kind of software applications managing data.
7.2. Requirements of the application example
For our particular application example, we characterize
the product line of a collection manager system according to
the following two sources of commonalities and two sources
of variabilities associated with kernel functionality and user
graphic presentation.