Maintaining Web Navigation Flows for Wrappers

Abstract

[Abstract]: A substantial subset of the web data follows some kind of underlying structure. In order to let software programs gain full benefit from these "semi-structured" web sources, wrapper programs are built to provide a "machine-readable" view over them. A significant problem with wrappers is that, since web sources are autonomous, they may experience changes that invalidate the current wrapper, so automatic maintenance is an important research issue. Web wrappers must perform two kinds of tasks: automatically navigating through websites and automatically extracting structured data from HTML pages. While several previous works have addressed the automatic maintenance of the components performing the data extraction task, the problem of automatically maintaining the required web navigation sequences remains unaddressed to the best of our knowledge. In this paper we propose and expirementally validate a set of novel heuristics and algorithms to fill this gap. © Springer-Verlag Berlin Heidelberg 2006