>Recommendation: If you are using XML in eclipse, DO NOT use JAXP….unless you specifically set the the system property to control which XSLT, XML, and XPATH processors that you use.
The reason for this is that you can receive some weird errors that will leave you scratching your head. Items like StackOverflows from URI Resolvers as shown in Bug 226937. The problem I believe in this particular case is that the com.sun.org.apache.xalan ends up trying to access a ZIP file to resolve where the variables and functions reside, however, it doesn’t understand this and we get a Stack Overflow exception being tossed.
The problem with JAXP from a plugin stand point is that it grabs what ever is the system default processor to be used unless you override the system. It also grabs whatever the default Resolver is for either XSLT, XML, or XPath. So this can cause different behavior from system to system depending on what parsers are installed and what URI Resolvers are setup and when. JAXP may provide a common API but unfortunately the behavior and results you can get can vary. Avoid it if possible when doing plugin development, if you must use it, be specific about the parser you want JAXP to use.