[PROPOSAL] XPath task

Stephane Bailliez 23 Apr 2001 15:15:52 -0000

Following discussion w/ Scott and Jeff in alexandria-dev, I quickly wrote an
XPath task.


I'm not sure this is 'exactly' how it should be done...
this looks like more a feature of the replace task, but I also wanted the
multiple replace feature without parsing n times the xml document.

Use at as follows:

<xpath file="input.xml" tofile="output.xml">
        <apply select="/root/node/@attribute" value="newvalue"/>
        <apply select="/root/node/child/@attribute" value="newvalue"/>
</xpath>

or simply:

<xpath file="input.xml" select="/root/node/@attribute" value="newvalue"/>

So here is the XPath task, with testcase and doc.

I used the package org.apache.tools.ant.taskdefs.optional.xpath
Feel free to change it to a more appropriate one (for instance if it is to
be used in cjan or alexandria).

Cheers,

-- 
 St�phane Bailliez 
 Software Engineer, Paris - France 
 iMediation - http://www.imediation.com 
 Disclaimer: All the opinions expressed above are mine and not those from my
company.

TestXPath.java
Description: Binary data

XPath.java
Description: Binary data

Title: XPath Task

XPath

Stephane Bailliez ([EMAIL PROTECTED])

Requirements

This task requires Xalan 2.x and a JAXP compliant parser.

Description

Invokes the Xalan XPath API over an XML document and replace specified node values by new values.

Parameters

Attribute	Description	Required
file	The XML file to which the Audit result should be written to.	Yes
tofile	The XML file resulting from the XPath modifications.	No (default is to modify the source file)
select	The XPath _expression_ that select nodes to process.	No. (Yes if select is set)
value	The value to replace	No. (Yes if select is set)

Nested elements

apply

An XPath _expression_ to apply on the XML document.

Attribute	Description	Required
select	The XPath _expression_ that select nodes to process.	Yes.
value	The value to replace	Yes.

Note that XPath expressions will be evaluated in the order they are declared. The one declared as attributes of xpath being the first one (if declared).

Example

  <xpath file="./xml/input.xml" tofile="./xml/output.xml">
      <apply select="/root/nodea/@attr1" value="newvalue1"/>
      <apply select="/root/nodeb/@attr5" value="newvalue5"/>
  </xpath>

This invokes XPath and replace the value of the selected attributes by respectively newvalue1 and newvalue5, as indicated below:

Before	After
<root> <nodea attr1="oldvalue1"/> <nodea attr1="oldvalue1"/> <nodeb attr5="oldvalue5"/> </root>	<root> <nodea attr1="newvalue1"/> <nodea attr1="newvalue1"/> <nodeb attr5="newvalue5"/> </root>