Towards a formal framework for JavaBeans and Enterprise JavaBeans

This project aims to provide a framework for the formal specification of JavaBeans and Enterprise JavaBeans (EJB), Sun Microsystems' component technology. We develop a list of properties that distinguishes beans from a Java class. For example, we formalise the notion of session beans, home/remote interfaces, etc. We also briefly touch upon the use of JavaBeans/EJB technology in a particular application

An Infrastructure for the Dynamic Distribution of Web Applications and Services

This paper presents the design and implementation of an infrastructure that enables any Web application, regardless of its current state, to be stopped and uninstalled from a particular server, transferred to a new server, then installed, loaded, and resumed, with all these events occurring "on the fly" and totally transparent to clients. Such functionalities allow entire applications to fluidly move from server to server, reducing the overhead required to administer the system, and increasing its performance in a number of ways: (1) Dynamic replication of new instances of applications to several servers to raise throughput for scalability purposes, (2) Moving applications to servers to achieve load balancing or other resource management goals, (3) Caching entire applications on servers located closer to clients.National Science Foundation (9986397

A component-based collaboration infrastructure

Groupware applications allow geographically distributed users to collaborate on shared tasks. However, it is widely recognized that groupware applications are expensive to build due to coordination services and group dynamics, neither of which is present in single-user applications. Previous collaboration transparency systems reuse existing single-user applications as a whole for collaborative work, often at the price of inflexible coordination. Previous collaboration awareness systems, on the other hand, provide reusable coordination services and multi-user widgets, but often with two weaknesses: (1) the multi-user widgets provided are special-purpose and limited in number, while no guidelines are provided for developing multi-user interface components in general; and (2) they often fail to reach the desired level of flexibility in coordination by tightly binding shared data and coordination services. In this dissertation, we propose a component-based approach to developing group- ware applications that addresses the above two problems. To address the first prob- lem, we propose a shared component model for modeling data and graphic user inter- face(GUI) components of groupware applications. As a result, the myriad of existing single-user components can be re-purposed as shared GUI or data components. An adaptation tool is developed to assist the adaptation process. To address the second problem, we propose a coordination service framework which systematically model the interaction between user, data, and coordination protocols. Due to the clean separation of data and control and the capability to dynamically "glue" them together, the framework provides reusable services such as data distribution, persistence, and adaptable consistency control. The association between data and coordination services can be dynamically changed at runtime. An Evolvable and eXtensible Environment for Collaboration (EXEC) is built to evaluate the proposed approach. In our experiments, we demonstrate two benefits of our approach: (1) a group of common groupware features adapted from existing single- user components are plugged in to extend the functionalities of the environment itself; and (2)coordination services can be dynamically attached to and detached from these shared components at different granules to support evolving collaboration needs

A responsive client architecture with local object behavior deployment

Information Systems with a large user base require thin client technology due to deployment issues. Configuration and version management, added to maintenance cost are major players on this decision. However, heavy traffic loads and network latency impose severe penalties on users. A candidate solution to this problem must optimize users ergonomics whilst keeping maintenance costs low. In a straightforward approach, client architectures should provide web deployable local processing facilities. This paper describes an architecture based on the MVC paradigm capable of porting portions of the system to client executable scripts. Required entities are encapsulated in XML carriers and exchanged on demand between client and server side systems. Numerous user interactions are executed on the client side, relieving the network and improving responsivity. This solution not only enhances ergonomics but is also highly scalabled, delegating tasks to the greater number of client machines, whereas focusing server activity on more relevant operations

Interactive Web Portal Application for Ambalta School for Children with Autism

Abalta is a school, based in Galway, designed to educate children who suffer from autism. The school was borne out of the identified need for children with autism to get a specific focused education. In July, 2001, four sets of parents came together, using their own personal funds, to establish the school and had it up and running by September, 2001. It took months of hard work, political negotiating, and lobbying, culminating with a high court case to attain funding from the state. In today\u27s Internet-oriented world, a web application is essential for businesses, organiiations and individuals to optimiie their impact on the world: to reach more people, be more efficient, learn more and achieve their goals. As Abalta School is ever expanding, there is an extensive need for a web portal for the school. A web portal will provide the school with a means of sharing information on autism and answering questions that people may have. Currently, when a person requires information, they contact the school and the school principle is the person who answers questions. The principle can spend at any one time, up to an hour answering questions on the telephone, sending brochures to people and explaining the methodologies used by the school. Having a web portal would enable the staff and employees of Abalta to save time and effort by directing people to the web portal where questions can be answered and sought-after information can be found

Attribute based component design: Supporting model driven development in CbSE

In analysing the evolution of Software Engineering, the scale of the components has increased, the requirements for different domains become complex and a variety of different component frameworks and their associated models have emerged. Many modern component frameworks provide enterprise level facilities and services, such as instance management, and component container support, that allow developers to apply if needed to manage scale and complexity. Although the services provided by these frameworks are common, they have different models and implementation. Accordingly, the main problem is, when developing a component based application using a component framework, the design of the components becomes tightly integrated with the framework implementation and the framework model is embedded in the component functionality, and hence reduces reusability. Another problem arose is, the designers must have in-depth knowledge of the implementation of a component framework to be able to model, design and implement the components and take advantages of the services provided. To address these problems, this research proposes the Attribute based Component Design (AbCD) approach which allows developers to model software using logical and abstract components at the specification level. The components encapsulate the provided functionality, as well as the required services, runtime requirements and interaction models using a set of attributes. These attributes are systemically derived by grouping common features and services from light weight component frameworks and heavy weight component frameworks that are available in the literature. The AbCD approach consists of the AbCD Meta-model, which is an extension of the บML meta-model, and the Component Design Guidelines (CDG) that includes core Component based Software Engineering principles to assist the modelling process for designers. To support the AbCD approach, an implementation has been developed as a set of plug-ins, called the AbCD tool suite, for Eclipse IDE. An evaluation of the AbCD approach is conducted by using the tool suite with two case studies. The first case study focuses on abstraction achieved by the AbCD approach and the second focuses on reusability of the components. The evaluation shows that the artefacts produced using the approach provide an alternative architectural view to the design and help to re-factor the design based on aspects. At the same time the evaluation process identified possible improvements in the AbCD meta-model and the tool suite constructed. This research provides a non-invasive approach for designing component based software using model driven development

A Framework For Dynamic Updating In Component-based Software Systems

Setiap sistem perisian (software) perlu dikemas kini setiap masa bagi pelbagai alasan seperti penetapan pepijat (fixing bugs) Every software system needs to be updated over time for different reasons such as fixing bugs, upgrading its components, or adapting the system in response to its environment's changes