manufacturing environments has been to develop Web-
based PDM systems with a standardized Web framework.
Such efforts have been reported, but they are not yet able to
provide the desired flexibility and security.
The Java 2 Platform, called the Enterprise Edition
(J2EE) of Sun Microsystems, has been known as a
framework for developing multi-tiered, global enterprise
applications under Internet environments. The J2EE
architecture is a component architecture for the develop-
ment and deployment of component-based distributed
business applications. In particular, the technology of
Enterprise JavaBeans (EJBs) is the key element of J2EE,
and makes it possible to develop distributed, transactional,
secure, and portable applications rapidly and simply, based
on Java technology. This paper proposes a component-
based product data management (CPDM) system that is
fully compatible with the J2EE architecture. The CPDM
system composed of EJB components is aimed at assuring
flexibility, security, stability, and maintainability by using a
standard architecture that takes full advantage of the J2EE
technology.
In this paper, the development background of the CPDM
system will be discussed first. Then, its functional and
architectural requirements will be presented. The compo-
nent-based development (CBD) approach to develop EJB
components will also be described. Next, the whole
development procedure will be illustrated with examples
of component design. The CPDM system will also be
tested for performance. Finally, conclusions will be drawn
and opportunities for further research will be discussed.
2 Component-based PDM (CPDM) system being fully
compatible with J2EE
2.1 Development background
The major Korean electronics and automobile companies
have been driving eManufacturing for effective product
development. They have invested heavily in developing
engineering information systems, including drawing man-
agement systems, engineering data management systems
(EDMS), and product data management (PDM) systems.
The reasons for the investments are to reduce the time to
market, improve design productivity, and improve design
and manufacturing accuracy by means of engineering
information integration and management. Reportedly, they
have achieved significant improvements in productivity
and competitiveness. Now, they are improving existing
systems or replacing them with new ones based on Web
technology. Specifically, they are developing globalized
mechanisms or tools for information sharing to support
global collaborative product commerce.
The major commercial PDM systems, including Meta-
phase (SDRC), SherpaWorks (Inso), Enovia (IBM), CMS
(WTC), Windchill (PTC), and Smarteam (Smart Solu-
tions), are known to support five user functions, including
data vault and document management, workflow and
process management, product structure management, parts
management, and program management. These systems
have played an import role in the manufacturing industry
by integrating and managing all applications, information,
and processes during the associated product life cycle.
Under global manufacturing environments, however, such
traditional commercial PDM systems have limits. For
example, these PDM systems use C/C++ as the major
building language, which is dependant on the hardware
platform, and so, a separate client program must be
installed on each user platform [1]. Therefore, they limit
access to users in different locations, especially those on
different networks. In other words, they are platform-
dependent and not easy to extend. To get over such
deficiencies, this paper proposes to develop a Web-based
PDM system which has full functionality under global
manufacturing environments. The Web-based PDM will
allow any users who have Internet access to use various
PDM services, which will provide platform-independence,
and allow easy global access across the whole world.
A recent advance in PDM technology has capitalized on
using Web-based technologies, including HTML/XML,
Java/RMI, CORBA, and COM. The legacy PDM systems
have been modified to allow users to access some of their
existing functions via a Web interface restrictively or just to
view product data through a Web browser. Of the many
PDM products currently available, it would appear that
very few products have taken full advantage of Web-based
technologies [2].
Two major frameworks, .NET (Microsoft) and J2EE
(Sun Microsystems), have appeared on the market in recent
years which can be incorporated in developing Web-based
systems. The enterprise-wide Web-based systems should
be able to provide the following distributed large-scale
services [3]:
– Highly available, to meet the needs of today’s global
business environments
– Secure, to protect the privacy of users and the integrity
of the enterprise
– Reliable and scalable, to ensure that business transac-
tions are processed accurately and promptly
J2EE has been used to define the standard architecture
for developing enterprise applications. It provides the
framework to develop the standardized, modular, and
distributed components that give rise to distributed large-
scale services. J2EE applications can be rapidly deployed
and easily enhanced, so that enterprises can more easily
respond to competitive pressures. Under the J2EE
architecture, enterprise services can be implemented
through three-tier applications in most cases. The first
tier, called the presentation tier, is implemented as JSP/
servlet components. It provides users with easy access to
business complexities, and eliminates or reduces drasti-
cally the associated user administration and training load.
The middle tier, called the business logic tier, has business
service components to handle the core business logic of the
application system. The third tier, called the data tier, is
responsible for the enterprise information systems (EISs),
including database systems, transaction processing sys-
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