265 research outputs found
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
Implementing a map based simulator for the location API for J2ME
The Java Location API for J2METM integrates generic positioning and orientation data with
persistent storage of landmark objects. It can be used to develop location based service
applications for small mobile devices, and these applications can be tested using simulation
environments. Currently the only simulation tools in the public domain are proprietary
mobile device simulators that are driven by GPS data log files, but it is sometimes useful to
be able to test location based services using interactive map-based tools. In addition, we
may need to experiment with extensions and changes to the standard API to support
additional services, requiring an open source environment. In this paper we describe the
implementation of an open source map-based simulation tool compatible with other
commonly used development and deployment tools
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Reconfiguration in the Enterprise JavaBean Component Model ; CU-CS-925-01
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
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Javaserver page, Java servlet and JavaBean technology: Online real estate company
This project will simulate an online real estate company using JSP, Java Servlet and JavaBean technology
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
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
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
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