Process maven's pom xml file with xmlstarlet

General command  to get version of certain plugin dependency from pom file:

xmlstarlet sel -N pom=http://maven.apache.org/POM/4.0.0 -t -m "/pom:project/pom:build/pom:pluginManagement/pom:plugins/pom:plugin[pom:artifactId='maven-checkstyle-plugin']/pom:dependencies/pom:dependency[pom:artifactId='checkstyle']/pom:version" -v . pom.xml

Examples for editing and selection are at:
https://github.com/sevntu-checkstyle/sevntu.checkstyle/blob/master/pom-version-bump.sh

https://github.com/checkstyle/checkstyle/wiki/How-to-generate-Checkstyle-report-for-Google-Guava-project

Few XPATH conditions for query:
http://stackoverflow.com/questions/28370054/find-a-specific-groupid-from-a-maven-pom-xml-using-xmstarlet


Useful command to print all tags from xml file to help construct XPATH:
xmlstarlet el -v pom.xml