I have started working on a project where I will need to share a bunch of Java
classes across a bunch of apps. In Eclipse
it was possible to create
You need to think in the eclipse projects as Android Studio/IntelliJ Idea modules. Then, you can generate android (or java) libraries and then include them in your project.
To mark an Android Studio module as a library you can go to File -> Project Structure -> Facets and there click on Library Module