Method Engineering: A Service-Oriented Approach - Intentional Perspectives on Information Systems Engineering - page 339

a class diagram. Let us note that the domain is not indicated, so the service is
domain-independent.

5.2 The Process Part

This part describes a process for achieving the service goal. The process part con-
tains three elements (see Fig. 6) : an initial situation, a final situation, and a process
structure.
The initial situation indicates pre-conditions and artifacts necessary to process
realization. The final situation specifies the results and the post-conditions of the
process. The initial and final situations are described with process ontology terms.
A process structure can be atomic, composite, simple or decisional. Atomic pro-
cesses realize elementary goals; these goals are not decomposable into sub goals. An
atomic process is considered as an operational process. Composite processes corre-
spond to complex goals; they contain constituent processes organized with control
constructs. Control constructs indicate the manner in which constituent processes
are executed. In SO2M, constituent processes execution may be in sequence (i.e. in
a specific order) or in parallel (i.e. without a particular order). Constituent processes
within a composite process may be atomic or simple.
Decisional processes are a specific case of composite processes. Decisional pro-
cesses propose several alternative decompositions of a goal. Each de-composition

Legend : Elements annoted with
(Lgoal), (Lact), (Lproc), (Lprod) refer
respectively to the goal ontology,
the actor ontology, the process
ontology and the product ontology

Process part
1

(L goal )
Goal

(L goal )
Goal

(L goal )
Goal
1

realize

1 1

1 1

1..* (Lproc)

Initial
situation

(Lproc)
Final
situation

Process Process Process

1..*

1..*

Decisional Decisional Decisional

Atomic Composite Simple

1..* 1..* 1..*

1 1..*

1

(Lproc)
control
construct

"choice"
control
construct

Constituent
process

Fig. 6 Process part of a method service