Patent ID: 7315981
Filing Date: 2008-01-01
Classification: G06F

Abstract:
1. A document processing computer system comprising a CPU and a main memory: said main memory comprising an XPath storing part which stores a plurality of XPath expressions; said CPU comprising a data structure-generation part for generating a data structure with redundant elements of said plurality of XPath expressions stored in said XPath-storing part being omitted; and said CPU further comprising an evaluation execution part for evaluating said plurality of XPath expressions with respect to a data file to be evaluated by using said data structure generated at said data structure-generation part of said CPU; (a) wherein said data structure-generation part of said CPU comprises: a step decomposing means for decomposing individual said XPath expressions into steps wherein a step comprises an axis, a set of tests, and a predicate; and a tree generation means for generating a data structure, in which a step common to a plurality of XPath expressions is associated with a node by associating a node with each step obtained from the decomposition; and (b) wherein when said data structure-generation part of said CPU updates a data structure by generating a new node for a part which does not have a node corresponding to said data structure in newly added XPath expressions, whereby if an XPath expression stored in said XPath storing part of said main memory is changed to form a newly added XPath expression, said data structure-generation part of said CPU adds the new node to the data structure, and removes only a node corresponding to a part unique to the XPath expression from nodes of said data structure corresponding to a part of deleted XPath expressions.