In netbeans, you can use the feature to you enter code.

You can use the feature of Code editor in net beans to edit and enter the code.
When you have two projects in netbean you can set one project as main project to run it in an easier way.
NetBeans is a software development platform and it is written in Java and NetBeans IDE is easy to install and you can use it straight away and it runs on many platforms which includes Windows, Linux, Mac OS X and Solaris.

I’d say platform as a service (paas) or application platform as a service (apaas) or platform base service is a category of cloud computing services that provides a platform allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure typically associated with developing and launching an app.