An emerging trend in Social Networking sites and Web portals is the opening up of their APIs to external application develop- ers. For example, the Facebook Platform, Google Gadgets and Yahoo! Widgets allow developers to design their own applications, which can then can be integrated with the platform and shared with other users. However, current APIs are targeted towards develop- ers with programming expertise and database knowledge; they are not accessible to a large class of users who do not have a programming/database background, but would nevertheless like to create new applications. To address this need, we have developed the AppForge system, which provides a WYSIWYG application development platform. Users can graphically specify the components of webpages inside a Web browser, and the corresponding database schema and application logic will be automatically generated on the fly by the system.
Read the rest of this entry »
With the rise of model-driven development, model repositories are intended to facilitate research in model engineering and consequently in domain-specific modeling. Model repositories are central places where all kinds of modeling artifacts (e.g., meta-metamodels, metamodels, models, and possibly transformation models) are stored and coordinated. They can serve as a platform for making available the specification of metamodels to others (typically necessary for domain-specific modeling languages) and for exchanging models, as well as a resource for teaching/learning materials.
Read the rest of this entry »
Starting Excel
1. Main Menu: Contains all features in Excel.
2. Tool Bars: Standard Tool Bar and Formatting Tool Bar. These allow you quick access to commonly used tools.
3. Cell: The standard unit you work with in Excel.
4. Worksheet: The workspace of Excel.
5. Task Pane: Shows current options of your currently selected category.
6. Worksheet Tabs: Multiple Worksheets, easily changed by clicking on the tabs.
Read the rest of this entry »
This tutorial covers the main packages in the Spring Framework. For full details, we refer you to Rod Johnson’s book, Expert One-on-One J2EE Design and Development, published by Wrox Press in 2002. The book’s ISBN number is 1-86100-784-1. The code for the Spring Framework is contained in package com.interface21. We provide UML diagrams for the subpackages, as well as code samples.
Read the rest of this entry »
The concurrency is an important issue to tackle when modelling real-time applications which are intrinsically concurrent. According to the definitions of real-time given in (CNRS 1988) and (Stankovic 88), real-time implies on one hand that the response are waited at a precise moment (neither before nor after) and on other hand, that such systems are coupled with the real world, therefore highly concurrent. This document overviews the support for concurrency modelling provided by UML. It describes first the main concept of active object and second a (non exhaustive) list of issues pertaining to concurrency mechanism interactions. The integration of concurrency issues within object-oriented environments generated a large amount of research.
Read the rest of this entry »