Setup Jetty to run with Debugging enabled on port 8000
export MAVEN_OPTS="-Xdebug -Xrunjdwp:transport=dt_socket,server=y,address=8000"
Run Jetty using Maven Plugin
mvn jetty:run
In NetBeans, Goto Debug→ Attach Debugger menu. Select Java Debugger(JPDA) and specify the port as 8000. Now you can debug the webapplication using NetBeans.