| dc.description.abstract | When it became obvious that Object Oriented software applications were falling short
of their promise of significant software reuse, the software industry began to look at
another solution. Hence the interest in Component Technology. If developers have the
means to use off the shelf components, application development time can be reduced
and quality will improve. Components are by nature modularised and are more
maintainable than other software applications, with easy integration of component
versions. When companies want to minimise the expense of developing in-house
solutions and the inflexibility of bought-in software, components are introduced,
allowing assembly of components into customised solutions.
Presently, there are three main component driving forces, the OMG with the CORBA
Component Model (CCM), Microsoft with COM Components (COM) and Sun with
Enterprise Java Beans (EJB).
Enterprise Java Beans is the Java component architecture for developing server side
components, as opposed to Java Beans, which is used to develop client side
components. Threading, persistence, and security are handled by an EJB Container.
All types of components will have to reside in a repository for application developers to
find them. In time it will become crucial to be able to query this repository and to view
component descriptions. As the situation stands, the EJB Deployment Descriptor does
not provide enough semantic information for a developer to understand exactly what a
component does.
This thesis examines ways of storing components and extracting information
transparently from them. It also examines ways of describing component semantics in a
way that is extensible. Developers in the future, who realise that certain semantic
information is crucial in a component description can create descriptions in a controlled
way, and other developers can search this data. The descriptions developed are XML
documents, and can be applied to all types of components, even though this thesis
focuses on EJBs primarily. | en |
