Architectural styles for active documents

This paper proposes several novel architectural styles for active documents. Active documents are documents that contain not only data, but also servlets, applets, expressions in spreadsheet languages, and other forms of software. To grasp the different forms of architectures, several novel concepts are defined. Invasive document composition is a type-safe form of template expansion and extension; transconsistency is a form of transclusion for architectures; and staged architectures provide a form of staged programming on the architectural level. With these concepts, it is possible to explain the architectures of many document processing applications for Web and office, and we define the architectural styles of wizard-parametrized, script-parametrized, transconsistent, stream-based, and staged active documents. Finally, we give a hypothesis of active document composition: it consists of four elements, namely, explicit architecture, invasiveness, transconsistency, and staging. On the basis of this hypothesis, many applications in Web engineering and document processing get a common background, and can be compared and simplified.