Developing Collaborative XML Editing Systems

In many areas the eXtensible Mark-up Language (XML) is becoming the standard exchange and data format. More and more applications not only support XML as an exchange format but also use it as their data model or default file format for graphic, text and database (such as spreadsheet) applications. Computer Supported Cooperative Work is an interdisciplinary field of research dealing with group work, cooperation and their supporting information and communication technologies. One part of it is Real-Time Collaborative Editing, which investigates the design of systems which allow several persons to work simultaneously in real-time on the same document, without the risk of inconsistencies. Existing collaborative editing research applications specialize in one or at best, only a small number of document types; for example graphic, text or spreadsheet documents. This research investigates the development of a software framework which allows collaborative editing of any XML document type in real-time. This presents a more versatile solution to the problems of real-time collaborative editing. This research contributes a new software framework model which will assist software engineers in the development of new collaborative XML editing applications. The devised framework is flexible in the sense that it is easily adaptable to different workflow requirements covering concurrency control, awareness mechanisms and optional locking of document parts. Additionally this thesis contributes a new framework integration strategy that enables enhancements of existing single-user editing applications with real-time collaborative editing features without changing their source code

CBSE: an implementation case study

Over the last couple of years, the shift towards component based software engineering (CBSE) methods has become a cost effective way to get an application to implementation stage much earKer. Adoption of Component Based Development methods acknowledges the use of third party components wherever possible to reduce the cost of software development, shorten the development phase and provide a richer set of processing options for the end user. The use of these tools is particularly relevant in Web based applications, where commercial off the shelf (COTS) products are so prevalent. However, there are a number of risks associated with the use of component based development methods. This thesis investigates these risks within the context of a software engineering project and attempts to provide a means to minimise and or at least manage the risk potential when using component based development method

Using XML views to improve data-independence of distributed applications that share data

The development and maintenance of distributed software applications that support and make efficient use of heterogeneous networked systems is very challenging. One aspect of the complexity is that these distributed applications often need to access shared data, and different applications sharing the data may have different needs and may access different parts of the data. Maintenance and modification are especially difficult when the underlying structure of the data is changed for new requirements. The eXtensible Markup Language, or XML, has emerged as the universal standard for exchanging and externalizing data. It is also widely used for information modeling in an environment consisting of heterogeneous information sources. CORBA is a distributed object technology allowing applications on heterogeneous platforms to communicate through commonly defined services providing a scalable infrastructure for today\u27s distributed systems. To improve data independence, we propose an approach based on XML standards and the notion of views to develop and modify distributed applications which access shared data. In our approach, we model the shared data using XML, and generate different XML views of the data for different applications according to the DTDs of the XML views and the application logic. When the underlying data structure changes, new views are generated systematically. We adopt CORBA as the distributed architecture in our approach. Our thesis is that: views to support data-independence of distributed computing applications can be generated systematically from application logic, CORBA IDL and XML DTD.Dept. of Computer Science. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2002 .L86. Source: Masters Abstracts International, Volume: 41-04, page: 1113. Adviser: Richard Frost. Thesis (M.Sc.)--University of Windsor (Canada), 2002

Collaborative web whiteboard based on the SVG technology

As innovation on web standards proceeds, web browsers have the option of becoming the generic user interface for any computer application, even those involving extensive user interaction. This thesis is placed in the domain of web graphics, where we tried a standard based approach, relying on the SVG standard for web vector graphics. SVG is less supported than its propertary counterpart, Adobe Flash, but we use a recent shim library to bring SVG support to all browsers capable of running Flash content; this way, the advantages of the two technologies can be combined. The library, called ``SVG Web'', is unobtrusive with reference to the application code, simply requiring a certain style for javascript handling of SVG elements and sometimes simplifying the handling of the SVG tree and improving its portability also among native renderers. To investigate the our approach, we have developed a shared, web-based whiteboard which allows different users to interact across the network using standard web browsers and servers. The whiteboard is thought for quick sketches, and built with the requirement of being lightweight and portable both for the client and the server side. The resulting application is capable of providing a good level of user interaction, still remaining fairly simple and maintainable in its code. The important achieved outcome is the possibility of developing all client side logic with the same language (Javascript), with a strong integration between the graphic environment and the rest of client-side functions, including AJAX communications

Automated Testing of WS-BPEL Service Compositions: A Scenario-Oriented Approach

Nowadays, Service Oriented Architecture (SOA) has become one mainstream paradigm for developing distributed applications. As the basic unit in SOA, Web services can be composed to construct complex applications. The quality of Web services and their compositions is critical to the success of SOA applications. Testing, as a major quality assurance technique, is confronted with new challenges in the context of service compositions. In this paper, we propose a scenario-oriented testing approach that can automatically generate test cases for service compositions. Our approach is particularly focused on the service compositions specified by Business Process Execution Language for Web Services (WS-BPEL), a widely recognized executable service composition language. In the approach, a WS-BPEL service composition is first abstracted into a graph model; test scenarios are then derived from the model; finally, test cases are generated according to different scenarios. We also developed a prototype tool implementing the proposed approach, and an empirical study was conducted to demonstrate the applicability and effectiveness of our approach. The experimental results show that the automatic scenario-oriented testing approach is effective in detecting many types of faults seeded in the service compositions

IDL-XML based information sharing model for enterprise integration

CJM is a mechanized approach to problem solving in an enterprise. Its basis is intercommunication between information systems, in order to provide faster and more effective decision making process. These results help minimize human error, improve overall productivity and guarantee customer satisfaction. Most enterprises or corporations started implementing integration by adopting automated solutions in a particular process, department, or area, in isolation from the rest of the physical or intelligent process resulting in the incapability for systems and equipment to share information with each other and with other computer systems. The goal in a manufacturing environment is to have a set of systems that will interact seamlessly with each other within a heterogeneous object framework overcoming the many barriers (language, platforms, and even physical location) that do not grant information sharing. This study identifies the data needs of several information systems of a corporation and proposes a conceptual model to improve the information sharing process and thus Computer Integrated Manufacturing. The architecture proposed in this work provides a methodology for data storage, data retrieval, and data processing in order to provide integration at the enterprise level. There are four layers of interaction in the proposed IXA architecture. The name TXA (DDL - XML Architecture for Enterprise Integration) is derived from the standards and technologies used to define the layers and corresponding functions of each layer. The first layer addresses the systems and applications responsible for data manipulation. The second layer provides the interface definitions to facilitate the interaction between the applications on the first layer. The third layer is where data would be structured using XML to be stored and the fourth layer is a central repository and its database management system

Relational Extensions : Object-Relational and XML Extensions

Mòdul 2 del llibre Database Architecture. UOC, 20122022/202

Stress-Testing Remote Model Querying APIs for Relational and Graph-Based Stores

Recent research in scalable model-driven engineering now allows very large models to be stored and queried. Due to their size, rather than transferring such models over the network in their entirety, it is typically more efficient to access them remotely using networked services (e.g. model repositories, model indexes). Little attention has been paid so far to the nature of these services, and whether they remain responsive with an increasing number of concurrent clients. This paper extends a previous empirical study on the impact of certain key decisions on the scalability of concurrent model queries on two domains, using an Eclipse Connected Data Objects model repository, four configurations of the Hawk model index and a Neo4j-based configuration of the NeoEMF model store. The study evaluates the impact of the network protocol, the API design, the caching layer, the query language and the type of database, and analyses the reasons for their varying levels of performance. The design of the API was shown to make a bigger difference compared to the network protocol (HTTP/TCP) used. Where available, the query-specific indexed and derived attributes in Hawk outperformed the comprehensive generic caching in CDO. Finally, the results illustrate the still ongoing evolution of graph databases: two tools using different versions of the same backend had very different performance, with one slower than CDO and the other faster than it