Incremental build with NetBeans and Maven for hot jetty deployment

After my failed attempt to start Tomcat hot deploy from NetBeans with Maven, I tried berth. doc-plug-d file gave me an important hint:

The plugin will automatically ensure the classes are rebuilt and updated before deployment. If you change the source of the class and your development environment automatically compiles it into the background, the plugin will pick up the changed class.

If I look at $ myproject / target / classes / ... in the projects directory, I see that NetBeans does not compile or update the class file on save. I need to explicitly create a project to update the file, and jetty takes the change. (The plugin parameter "scanIntervalSeconds" is set to 1.)

How can I tell NetBeans to compile when I save and update the class file so that jetty can pick up the change?

Preliminary solution: "Project properties> Build> Compilation> Compile on save: both for application and for test execution". NetBeans warns me that the output does not match the output from the usal compiler, but it still works.