Semantically Integrating Portlets in Portals Through Annotation

Portlets are currently supported by most portal frameworks. However, there is not yet a definitive answer to portlet interoperation whereby data flows smoothly from one portlet to a neighboring one. One of the approaches is to use deep annotation. By providing additional markup about the background services, deep annotation strives to interact with these underlying services rather than with the HTML surface that conveys the markup. In this way, the portlet can extend portlet markup with meta-data about the processes this markup conveys. Then, the portlet consumer (e.g. a portal) can use this meta-data to guide mapping from available data found in markup of portlet A to required data in markup of portlet B. This mapping is visualised as portlet B having its input form (or other “input” widget) filled up. However, annotating is a cumbersome process that forces to keep in synchrony the meta-data and the resources being annotated (i.e. the markup). This paper presents an automatic process whereby annotations are generated from portlet markups without user intervention. We detail our prototype using Lixto Visual Wrappers to extract semantic data from the markup.