Instead to find where org.w3c.dom comes from I've been using this script:
mvn dependency:copy-dependencies -DincludeScope=test -DoutputDirectory=deps
for i in deps/*.jar; do if unzip -l $i| grep -q org.w3c.dom; then echo $i; fi ; done
There's actually a command to list all other commands that a Linux shell knows, but more than likely you're not familiar with it. If there's ever been a