The conversion of legacy single-user applications to collabo- rative multi-user tools is a recurrent topic in groupware settings. Many works tried to achieve collaboration transparency: to enable collabora- tive features without modifying the source code of the single-user appli- cation. In this paper, we present a novel blackbox solution that achieves complete transparency by intercepting user interface libraries and in- put events. This is the rst blackbox solution constructed on top of lightweight wrapper technologies (Aspect Oriented Programming) and unlike previous approaches it provides support to both AWT and Swing applications. Our solution solves four important problems: event broad- casting, management of external resources (random numbers), contex- tual information (telepointers) and transparent launching support. We validated our approach with several Swing-based and AWT-based tools demonstrating that our wrapper is generic and imposes very low over- head.

1. Enabling Collaboration Transparency with Computational Reflection Pedro García López Universitat Rovira i Virgili [email_address]

13. Best Launching Support: AOP + load-time weaving

14. Best Validation : low overhead