Tree automata and active XML

An Active XML (AXML for short) is an XML document where some of the data is given explicitly while other parts are defined only intentionally by means of embedded calls to Web services. Tree automata are extended from traditional string automata and accept regular tree languages. In this paper, the connection between tree automata and AXML was surveyed. Specially, the methods of how to build the corresponding AXML document tree automata (AXTA) and AXML schema tree automata (ASTA) were presented, given an AXML document and an AXML schema specification respectively. Based on AXTA and ASTA, the relative problems about AXML such as document rewriting and schema rewriting are can be resolved efficiently.