Rational XDE represents a significant step forward in making Web applications easier to architect and deploy, while at the same time freeing senior members on the development team to work on high-end projects, leaving the simpler Web-based projects to their less experienced team members. For Microsoft, XDE offers a way to give .NET developers the ability to design and analyse large applications before they get down to coding, says Prashant L Rao

M K bharatee finds that unlike Rational’s flagship product Rose, using Rational XDE does not require any training

Rational software sells software development tools to the likes of Infosys, Wipro, TCS and Microsoft. Its flagship product, Rose, had the drawback of requiring an understanding of object-oriented design—a skill possessed only by senior system architects. There was need for a tool for developers to quickly create Web-based applications using J2EE or .NET. Rational XDE is that tool. It has two flavours that plug into MS Visual Studio (.NET) and IBM WebSphere (J2EE). XDE has two key advantages—it gives developers a visual modelling tool that allows them to create design patterns (templates) that can be reused on later projects, dramatically cutting the time required to create applications. At the same time, it also lets architects and designers create code templates that do away with the conventional cutting and pasting of code that happens in most software houses.

While Rational Rose is aimed squarely at software architects and designers, Rational XDE is meant for developers working on smaller modules using either .NET or J2EE.

“You don’t need rigorous training to use XDE,” says M K Bharatee who is the country manager for Rational Software India. “To use Rational Rose you need to know OOAD (Object Oriented Analysis and Design) and UML (Rational’s modelling language that is an industry standard). For XDE you just need to know UML.”

While the first release of Rational XDE for Visual Studio.NET supported C#, the latest avatar adds support for VB.NET and ASP (Active Server Pages—Microsoft technology that lets developers create Web-based applications that work with databases). ASP is extremely popular in the Windows server world, all Web or three-tier applications created for Windows NT/2000 use this technology.

Visual Studio.NET is an IDE that provides the tools to edit, compile and create executable code. XDE adds visual modelling to that mix.

“In Visual Studio (not Visual Studio.NET) there used to be a visual modeller licensed by Microsoft from Rational. VS.NET doesn’t have a modeller,” says Sampathgiri Gopalakrishnan, software engineering specialist, Rational Software India.

While two-way tool functionality is possible by buying Microsoft Visio separately, the combination of Visio and VS.NET is not as powerful as Rational XDE with VS.NET.

XDE offers the ability to outline a UML diagram, generate skeleton code and modify that code (hand-coding). Now if the developer did this in Visio and went back and changed the diagram, his hand-coded changes would be overwritten. XDE doesn’t overwrite the hand code even when the UML diagram is altered at a later date.

The tool appears as one more menu item in Visual Studio.NET. It could be used to create any application using C#, VB.NET and ASP.NET. This includes commercial applications such as billing and inventory.

Daniel Ingitaraj says that with Rational XDE, Visual Studio .NET users have a high-level design pattern and analysis tool that can be used before coding

XDE shows up as a new menu within Visual Studio.NET IDE (Integrated Development Environment). “There are five stages in the software design life cycle. Visual Studio is meant for stage three, which is development. XDE caters to stage one and two—analysis and design,” says Daniel Ingitaraj, senior marketing manager at Microsoft India.

“With this tool Visual Studio.NET users have a very high-level design pattern and analysis tool that they can use before coding. It is well suited to projects requiring six man-months and above,” adds Ingitaraj.

The key advantage of using XDE is that it promotes reuse of both design and code. By using design patterns and code templates, architects can be sure that developers on their team are following their design vision. It also helps collaboration by letting developers split a model into multiple parts so that each can be worked on by a different person.

To promote XDE, Rational Software has distributed close to a thousand copies of the software to companies that are existing users of Rational Rose (Rational has well-established criteria for deciding who’s eligible). This includes the likes of Infosys, Wipro, MindTree, Motorola and Philips India development centres. Indian ISVs and MNC captive development centres account for 90 percent of Rational’s sales. The remainder is split 50:50 (5 percent each) over government and defence, and end-users.

With Rational XDE for Visual Studio.NET, Microsoft has finally got a design and analysis tool that works within its IDE. Without this tool, developers would be less likely to consider .NET for serious projects. With it, the chances of .NET being used to build mission-critical applications are much higher.