Saving the package
After you have created a new package or changed any of its contents you must save it in order to export the classes from your image. If you are about to save the package for the first time you may want to choose a particular directory in which the package file (with .PAC extension) will reside. You can do this using the Package/Save as command. As you might expect, on subsequent saves you can just use Package/Save or the Save toolbar button to export the contents.