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Concurrent software is composed of several active execution
units, such as processes, threads, Java applications and
applets, or CORBA business objects. These units are distributed
and concurrently executed over a concurrent execution infra-
structure. For concurrent software development, there are
several critical issues emerged but not addressed sequential
software, such as parallelism, distributed, communication, etc.
Besides, concurrent software often provides services to multi-
users, and different users require different services. Hence the
development of concurrent software is more complicated than that
of sequential software. Conventional software analysis and
design methods, including object-oriented analysis and design
methods which is convinced as the most efficient methods for
software development, mostly emphasize the development of
sequential software. They do not offer appropriate support to
the development of concurrent software. The goal of the thesis
is to propose a proper requirement analysis method of concurrent
software. The aim of the software requirement analysis is to
acquire the users'' requirements and then describe the
requirement specification unambiguously. Although concurrent
software is distributed on several computer systems, from the
user''s point, no perceptible difference between concurrent and
sequential software, and their requirements can be expressed as
a set of functional service requirement. However, to the
concurrent software system, each service is usually achieved
through the collaboration of several execution units. Therefore,
this thesis proposes "Functional Decomposition Object Oriented
Analysis for Concurrent Software" that is based on "Functional
Decomposition Object Oriented Analysis", with the extension of
the role concept to assist the requirement analysis of
concurrent software. We define a role as a basic execution unit
of the concurrent software system. The users with the same
(similar) requirement are given an environmental role to propose
their requirement in terms of a set of service requirements.
These service requirements are then analyzed with the techniques
of functional decomposition and bottom-up composition to
construct the software architecture. The system roles and the
interactions between different system roles should be defined to
delineate the collaboration required in the service
requirements. When the analysis is finished, the whole system is
composed of a group of roles, each of which is composed of a
group of objects and provides a series of services for other
roles. The products from the "Functional Decomposition Object
Oriented Analysis for Concurrent Software" are role model,
function model, class model, role deployment model, dynamic
model, object model, and the requirement specification. The role
model is used to express the roles included in the system and
the collaboration among them. The function model is used to
illustrate the function hierarchy and candidate objects. The
class model describes the classes included in the system and the
relationship among them. The role deployment model presents the
basic deployment of the roles in the concurrent software. The
dynamic model indicates the behavior of each class in terms of a
state transition diagram. The object model shows the global
behavior of the system by role interaction diagrams and object
interaction diagrams. The requirement specification is written
in the improved "An Object Oriented Rapid Prototyping Language".
We have applied our method to the requirement analysis of
"Meeting Arrangement Supporting System" successfully, and hereby
verify the feasibility of the analysis steps and the
expressiveness of the models and specification language.
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