Parsing XML quick learning with sample code

Hi, I got a need to learn how to parse a xml file in java, Actually I used and did same things 3 years ago, that time I used othar libraries(Xalan, Xerces) provided by Apache project. but this time I try and use part of the standard development kit of Java 6.0. that part is called JAXP.

Requrements:
My need with a XML parsing library is
1.load a xml based configuration file(i.e. server.xml for Tomcat)
2.update from a Swing based application

Steps:
For achiving this, what I am going to do with JAXP is looking at JAXP home website and know its overview and goals.

References:API , Tutorial(J2EE1.4)