From page-centric to portlet-centric Web development: Easing the transition using MDD

Portlet syndication is the next wave following the successful use of content syndication in current portals. Portlets can be regarded as Web components, and the portal as the component container where portlets are aggregated to provide higherorder applications. This perspective requires a departure from how current Web portals are envisaged. The portal is no longer perceived as a set of pages but as an integrated set of Web components that are now delivered through the portal. From this perspective, the portal page now acts as a mere conduit for portlets. Page and page navigation dilute in favor of portlet and portlet orchestration. However, the mapping from portlet orchestration (design time) to page navigation (implementation time) is too tedious and error prone. For instance, the fact that the same portlet can be placed in distinct pages produces code clones that are repeated along the pages that contain this portlet. This redundancy substantiates in the first place the effort to move to model-driven development. This work uses the eXo platform as the target PSM, and the PIM is based on Hypermedia Model Based on Statecharts. The paper shows how this approach accounts for portal validation/verification to be conducted earlier at the PIM level, and streamlines both design and implementation of eXo portals. A running example is used throughout the paper.