importing my application into NetBeans

I have created a rather large Java application from scratch - meaning that it was all done in Notepad (no IDE). Now I would like to import it into NetBeans and make it into a project. Is there a way to do this?

I am cross-posting this here: what is a build script?

I don't use Netbeans, but presume there is some sort of import available similar to eclipse, in which one would create a new project, on the src icon right click and import, from there you can select from the file system a directory structure. Something sounds strange if you are being asked for a build script

I get the requirement for a build script if I choose Java Free-Form Project.

But if I choose Java Project with Existing Source, I manage to get my project imported.