How to generate java files

When you have created a new project, you should see a new folder that appears in the project list.

Expand the project file list by clicking on the little arrow at the left of the project name.
Now take a look on the src folder (point 1 in the image).
Select a file and press on the generate java files button in the menu bar (point 2 in the image).
Now the dialog window should appear indicating that the compilation has been succesfully completed.
Now you can take a look at the generated files in the 'src-gen' folder (point 3 in the image).