The somewhat functional way of thinking involved with jOOX’s XML manipulation cries for an additional API enhancement simply supporting XSLT. XSL transformation has become quite a standard way of transforming large amounts of XML into other structures, where normal DOM manipulation (or jOOX manipulation) becomes too tedious. Let’s have a look at how things are done in standard Java

Example input:

<books>
  <book id="1"/>
  <book id="2"/>
</books>

Example XSL:

<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="1.0"
    xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

    <!-- Match all books and increment their IDs -->
    <xsl:template match="book">
        <book id="{@id + 1}">
            <xsl:apply-templates/>
        </book>
    </xsl:template>

    <!-- Identity-transform all the other elements and attributes -->
    <xsl:template match="@*|*">
        <xsl:copy>
            <xsl:apply-templates select="*|@*"/>
        </xsl:copy>
    </xsl:template>
</xsl:stylesheet>

Verboseness of XSL transformation in Java

The standard way of doing XSL transformation in Java is pretty verbose – as just about anything XML-related in standard Java. See an example of how to apply the above transformation:

Source source = new StreamSource(new File("increment.xsl"));
TransformerFactory factory = TransformerFactory.newInstance();
Transformer transformer = factory.newTransformer(source);
DOMResult result = new DOMResult();
transformer.transform(new DOMSource(document), result);

Node output = result.getNode();

Drastically decrease verbosity with jOOX

With jOOX, you can write exactly the same in much less code:

Apply transformation:
// Applies transformation to the document element:
$(document).transform("increment.xsl");

// Applies transformation to every book element:
$(document).find("book").transform("increment.xsl");

The result in both cases is:

<books>
  <book id="2"/>
  <book id="3"/>
</books>

From http://lukaseder.wordpress.com/2012/01/28/joox-and-xslt-an-xml-love-story-continued/