ApplyXPath and ApplyXPathDOM samples

[Tahura Chaudhry]

The two sample programs, ApplyXPath and ApplyXPathDOM, both read XML, 
construct a DOM document  from it and evaluate the given XPath expression. 
My question is what is the difference
between these two samples.

I understand that ApplyXPathDOM uses the DOM L3 XPath API.  If I'm writing a 
program that evaluates a given XPath expression for a given XML document, 
which of the two sample programs should I use as reference.

thanks,
Tahura