Reusability in Governmental Electronic Services

Reusability in the everyday life is the capacity of using existing objects or even concepts again in the same or other contexts. When applied to information systems reusability is the capability of using the same parts of an application in other applications or in other contexts. As defined by IEEE (IEEE, 1990), reusability is the degree to which a software module or other work product can be used in more than one computing program or software system. Although rapid application development environments such as MS Visual .NETTM (Visual .NET, 2005) and DelphiTM (Borland Delphi, 2005) have to some extent employed reusability of components to aid the fast implementation of software applications, the extent to which existing objects can be used again in the implementation of new software systems is usually limited to basic building blocks of the interface. One problem that hinders reusability of larger building blocks is the fact that once a component which encompasses a number of objects is built it also encapsulates algorithms (sets of well-defined instructions that perform a task) in the form of code that define the functioning of the component. Tight coupling between the program logic and the program code makes portability of the component between applications difficult, when even small modifications in the program logic are required. A second problem that hinders reusability is that even when the same component can be directly used between applications, recognizing that such a component exists and retrieving it, is not an easy task. Reusability plays an important role in software development industry. If a set of well-defined components is available, valuable resources can be saved by utilizing again these components. As Rich Seely observes (2003) “as part of that cost-saving message, Gartner recommends vendors and consultants focus on reusability of Web services applications and components.”