DiffX

A java API for comparing XML documents by analysing the sequence of XML events.

DiffX was designed only to handle small documents, but be

Overview

To invoke Diff-x from the command-line to compare two file, you can simply use the java -jar diffx-xx.jar command followed by the options below:

  Main [options] xml_file1 xml_file2
  where
     xml_file1 = Path to the new XML file
     xml_file2 = Path to the old XML file
  options:
    -profile    Display profiling info
    -noslice    Do not use slicing
    -o [output] The output file
    -L [loader] Choose a specific loader
                sax* | dom | text
    -A [algo]   Choose a specific algorithm
                fitsy* | guano | fitopsy | kumar | wesyma
    -F [format] Choose a specific formatter
                smart* | basic | convenient | strict | short
    -W [wsp]    Define whitespace processing
                preserve* | compare | ignore
    -G [granul] Define text diffing granularity
                word* | text | character
    * indicates option used by default.

Basic options

-o [output] option

By default, Diff-X sends the diffing results to the standard output. Use this option to specify in which file the diffing result should be stored. [output] should be a filename.

-L [loader] option

Choose a specific loader, to creates the sequence of events:

• Use sax to use a SAX parser (faster, but will ignore XML comments)
• Use dom to use the W3C DOM
• Use text to perform a simple text comparison

-W [wsp] option

Define whitespace processing.

• preserve White spaces are preserved for formatting but ignored during diffing.
• compare White spaces are preserved for formatting and white space differences are reported (slow)
• ignore white spaces are completely ignored and the result may produce different white spaces (faster)

-G [granul] option

Use this option to defines the granularity text diffing.

• word reports differences at the word level
• text reports differences at the text node level (faster)
• character reports differences at the character level (slow)

Advanced options

-profile option

Displays some profiling information on the error output

-noslice option

Prevents Diff-X from "slicing" the XML. Diff-X uses slicing to remove common subsequences at the beginning and at the end of the sequence of XML events.

-allowdoctype option

To prevent XML External Entity (XXE) attacks, doctype declarations are not allowed in the source XML. Use this option, to override this setting.

-A [algo] option

Choose a specific algorithm implementation to use. Use this option to test your own algorithm - these option values may change in the future. Must be one of fitsy* | guano | fitopsy | kumar | wesyma

-F [format] option

Choose a specific formatter. Must be one of smart* | basic | convenient | strict | short

Using Diff-X as an XSLT extension

Diff-X provides some static methods which can be used in XSLT as extension functions.

Saxon

To use Diff-X as an XSLT extension, you need to ensure that saxon-dom.jar is included in your classpath as Diff-X will compare DOM nodes.

In your XSLT, declare the namespace as:

 <xsl:stylesheet version="2.0" 
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
    xmlns:diffx="java:org.pageseeder.diffx.Extension"
    extension-element-prefixes="diffx">

Diff-X can then be called within your XSLT as an extension function as:

diffx:diff(node1, node2, whitespace_processing, text_granularity)"/>

With:

• node1 the first node to compare (Node)
• node2 the first node to compare (Node)
• whitespace processing to indicate how white spaces should be processed, valid options are COMPARE, PRESERVE or IGNORE (xs:string)
• text granularity to indicate the level of precision in text comparison, valid options are TEXT or WORD (xs:string)

For example, to compare two nodes ignoring whitespaces and detecting text differences at the word level, use:

  <xsl:copy-of select="diffx:diff(/node1/to/compare, /node2/to/compare, 'IGNORE', 'WORD')"/>

For more info on how to use saxon extension function, visit Saxonica's website: http://www.saxonica.com/documentation9.1/extensibility/functions.html

Older repositories

This is the official home of DiffX.

DiffX has moved over the years, after a short stint at https://sourceforge.net/projects/diffx/ We moved to https://code.google.com/p/wo-diffx/