Introduction

AIDA/Web is a web application server, which means it is also a framework for building dynamic web applications.

An application server has the following general requirements: it must handle user identification, access control, manage user sessions and provide a security policy. It should provide developers with a proper environment for fast and simple web site building using a familiar language. It should not bother them with all the details of HTML.

AIDA/Web satisfies all of these requirements with a strong framework, built using the Smalltalk language. The language is object-oriented, therefore each Aida web page is an object, constructed of sub-objects, such as web page elements. These can be combined into components that may be re-used for many different pages. Thus, Aida scales an object-oriented approach when building web pages and applications. The framework is also helpful for managing details, such as connecting web pages with hyperlinks. For example, it creates those links automatically, because the web link for Aida is just a reference (a pointer) between objects in the Smalltalk object model. Aida makes it possible to show each object as a web page, and links between objects become links between web pages.

Aida allows the separation of software dealing with presentation from software in charge for the functionality of an application. In Smalltalk, this approach is known as MVC (Model View Controler), and it has recently been adopted in the world of Java (i.e., Struts). By organizing an application following the MVC approach, we can separate (and thereby simplify) the functional logic of the system from the introductory level, which is in many cases is more complex and demands more code. Without this separation, the functional layer gets mixed with the presentation code, which aggravates maintenance and development in the future. These problems are typical when building pages using ASP, JSP or PHP.

By way of a conclusion, we'll dedicate a few words to the use of Aida in the field. Aida was developed in 1996 and has since been running a number of public and internal web sites. An early success was a mountaineering site, called Gore - Ljudje, using Aida since 1999. This site included both static and dynamic web pages, including discussion forums, real time statistics and more. Because of its dedication to highly dynamic web pages, Aida has been used in many business applications on company Intranets. Some examples include: Gas Billing System (AIDA/GBS), Gas Management System (AIDA/GMS), Logistics (e-logis), ISO 9000 Quality Management Portal (BiArt/ISO) Business Process Management (BiArt/BPM). See Success stories for more.

Aida is available under an open source license MIT, at www.aidaweb.si. Since it is written in Smalltalk, it can be run using various operating systems, including Windows, different Unix systems, and Linux.