Generating and Optimizing Graphical User Interfaces for Semantic Service Composition

Semantic Web service composition is a discovery process in which a given set of requirements are fulfilled by locating and assembling semantically annotated services. Semantic annotation of Web services is based on expanding the description of Web services with formal semantic models, such as OWLS [2]. These models provide an unambiguous description of service properties by relating them to concepts belonging to Web ontologies [3]. Dynamic composition is a new way for creating software applications. Rather than manual coding the new application, the application is generated automatically , at least partially, by reusing existing software services according to the user's requirements [6, 8]. The method has several advantages: a) it answers an instantaneous request of the user; b) the application is flexible, changing according to failures, price change, etc. While dynamic composition promises an exciting vision for software development, it raises several questions regarding the way users interact with the generated application. Specifically, it raises a challenge for usability, which is defined as the effectiveness, efficiency and satisfaction in which users perform tasks using a given system [1]. In traditional software development processes, the user interface is derived from the requirements and desired functionality of the application model. It can be carefully designed and tested in order to ensure its usability. In contrast, in dynamically composed applications, the functionality is not set during the design of the system. Therefore, the user interface cannot be designed, let alone tested for usability. The conclusion is that the user interface should be generated dynamically as well, reflecting the temporary functionality of the application. The field of automatic generation of user interfaces attempts to formally define the elements of user interfaces, including presentation and interaction, and using the formal model in order to generate user interfaces [7, 5]. While model-based user interfaces provide the foundations for automatic generation of user interfaces, they do not deal with usability optimization as they presume the models are already usable. However, this approach will not suffice for dynamic compositions, as these compositions are not optimized for usability. In this demonstration, we provide a model of user interface generation and optimization for dynamically-composed applications. Our framework, named Liquid-Interface, automatically generates form-based user interface from dynamic compositions. The Framework can be used online at: