RegeXPath Expressions
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This package provides a number of utilities and a library that facilitate the processing of streaming XML files using XPATH and regular expressions.
They should prove especially useful to extract data from XML streams or very large XML files.
As such, the focus is on speed and simplicity rather than expressivity.
If you are looking for a full implementation of XPATH, this is not the software you are looking for.
If, on the other hand, you are looking for an easy to use and fast way to extract information from your XML data, this might save your day.

At the core of this package is a set of XPATH based SAX filters that can select information from the XML of your choosing.
These filters eagerly evaluate the XPATH expressions, that is, the filtered out information will be returned as soon as possible.
This minimizes memory usage and enables the construction of a pipeline.
Eager evaluation also means that results will be returned even for incorrect XML files, at least before the error occurs.
Recovery from errors depends entirely on the error and the particular selection you have chosen.

Based on the filters, this package supplies two utilities.
- A commandline utility xml2csv, that can be used to convert XML files to tables represented by comma separated values (CSV).
- A java annotation library that calls XPATH annotated functions for each matching entry in some XML file.


Use-cases

- Importing XML data into an SQL database or more generically, extracting table based information from an xml database. The filters could very well be used to create a stand alone utility that allows one to extract tables, such as csv files, from an xml file. However, when importing data to a normalized database with respect to the XML structure, it is probably more effective to use the annotations.
- Authentication layer for a SOAP server
- Monitoring and logging XML streams
- Interpreting a GUI definition file