Patent ID: 7073122
Filing Date: 2006-07-04
Classification: G06F

Abstract:
1. A method for extracting structured data from HTML pages, comprising the steps of: (a) parsing the input HTML file using a standard HTML parser, thereby creating a parse tree; (b) annotating the parse tree generated in step (a), thereby creating an annotated parse tree; (c) creating an array of nodes from the annotated parse tree generated in step (b) and a set of constraints, thereby creating a filtered node array; and (d) generating an instance tree by instantiating a given structure template with respect to the filtered node array generated by step (c), wherein the step of generating an instance tree further includes the step of instantiating a composite structure element with respect to a subsequence of the nodes in the filtered node array, thereby creating a composite instance, said step of instantiating a composite structure element includes the step of successively instantiating each of the children of said composite structure element with contiguous subsequences of the subsequence of the filtered node array; wherein step (c) further comprises the steps of: the structure template comprises a plurality of structure elements arranged in a hierarchy; each structure element in said plurality of structure elements is selected from the group consisting of an ExField structure element, a composite structure element, a repeat structure element, and a choice structure element; said structure elements include at least one ExField structure element; said instance tree comprises a plurality of instances arranged in a hierarchy; each instance in said plurality of instances is selected from the group consisting of an ExField instance, a composite instance, and a repeat instance; and said instances include at least one ExField instance.