A concept and implementation of higher-level XML transformation languages

In the software development (e.g. with product lines or refactoring) transformations play an increasing role. To ease and automate these transformations, we propose a solution based on the operator hierarchy concept. It allows to define transformation operator hierarchies containing different levels of transformation operators. The operators capture reusable knowledge units. The concrete realization of such a higher-level transformation language construction is demonstrated by an application of the XML operator hierarchy concept to the transformation language XSLT. XSLT serves as an example which is employed to provide the elementary transformation operators. On top of these elementary operators the layered concept allows the definition of new higher-level operators, e.g. domain-independent and domain-specific ones. In an application example the construction of the higher-level language XML2DSV is presented. This is a stand-alone domain-specific transformation language, which can be used to create delimiterseparated values (DSV) files from XML documents, on the base of XSLT. We developed XTC (XML Transformation Coordinator) to automate the multi-level transformation process. ! 2008 Elsevier B.V. All rights reserved.