A Component-Based Geo-Workflow Framework: A Discussion on Methodological Issues

Abstract

Software framework (SF) brings forth lots of conveniences for software reuse in specific domains. It is well-known that a framework is much harder to be developed than a common reusable component. Based on the conception of component-based software framework (CBSF) that provides black-box reuse approach, a development process for geo-workflow domain is in discussion. A geo-workflow application is one sort of workflow management systems applied in the geographic information domain, and can be implemented through reusing component-based geo-workflow framework (CBGWF). From the methodological point of view, the following steps are necessary to develop a CBGWF: domain analysis, domain design, framework design and implementation. The outputs of them are domain models with identified variabilities, domain-specific software architecture (DSSA), and products of software framework, respectively. In the context of geo-workflow, domain variabilities, which areidentified and classified first, involve variabilities of geospatial data types, variabilities of geospatial data management, variabilities of geospatial operations, variabilities of processes, and variabilities of geospatial data representation. These variabilities can be organized in a tree view. Then, using HMB style, DSSA and architecture of CBGWF are designed, where the former can be regarded as a template of the latter. Finally, the framework component development based on EJB component model and the reuse of CBGWF are described in brief. Compared with other geo-workflow systems, the main advantage consists in its flexibility caused by the extensibility of CBGWF.