Question

Is there an easy way (perhaps using the DOM api, or other) where I could remove the actual data from an XML file, leaving behind just a kind of template of its schema, so that we can see what potential information it can hold.

I will give an example, to make this clear.

Consider the users inputs the following xml file:

<photos page="2" pages="89" perpage="10" total="881">
    <photo id="2636" owner="47058503995@N01" 
        secret="a123456" server="2" title="test_04"
        ispublic="1" isfriend="0" isfamily="0" />
    <photo id="2635" owner="47058503995@N01"
        secret="b123456" server="2" title="test_03"
        ispublic="0" isfriend="1" isfamily="1" />
    <photo id="2633" owner="47058503995@N01"
        secret="c123456" server="2" title="test_01"
        ispublic="1" isfriend="0" isfamily="0" />
    <photo id="2610" owner="12037949754@N01"
        secret="d123456" server="2" title="00_tall"
        ispublic="1" isfriend="0" isfamily="0" />
</photos>

Then I want to transform this into:

<photos page=“..." pages=“..." perpage=“..." total=“...">
    <photo id=“.." owner=“.." 
        secret=“..." server=“..." title=“..."
        ispublic=“..." isfriend=“..." isfamily=“...” />
</photos>

I’m sure this could be written manually, but would be the be best, most efficient and reliable way of doing this. (preferably in Java).

Thnx!

Answer 1

There are plenty of possibilities:

• DOM API (included in JDK)
• SAX API (included in JDK)
• JDOM (easy to use, but external)
• XSLT (transforming XML with prepared XSL stylesheet, JDK supports XSLT 1.0)

I think that XSLT is most reliable and universal way to transform XML into another XML. Here is some quick example:

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
    <xsl:strip-space elements="*"/>
    <xsl:output method="xml" indent="yes" omit-xml-declaration="yes"/>

    <xsl:template match="node()">
        <xsl:copy>
            <xsl:apply-templates select="@*|node()[position()=1]"/>
        </xsl:copy>     
    </xsl:template>

    <xsl:template match="@*">
        <xsl:attribute name="{name()}">...</xsl:attribute>
    </xsl:template>
</xsl:stylesheet>

Result:

<photos page="..." pages="..." perpage="..." total="...">
   <photo id="..." owner="..." secret="..." server="..." title="..." ispublic="..."
          isfriend="..."
          isfamily="..."/>
</photos>