A package is used to store related classes. And a package is just like a folder.
In eclipse, I create a package "SimpleGUI" in src directory, and create another package "SimpleGUI.model". Actually, "SimpleGUI.model" is a folder "model" in .../src/SimpleGUI
So I should be able to regard everything in folder "model" as something that is also in folder "SimpleGUI". So I should also be able to regard a class in package "SimpleGUI.model" as a class in package "SimpleGUI". (Is this true?)
However, , in package "SimpleGUI", when I try to use a class that is defined in package "SimpleGUI.model", I have to import SimpleGUI.model.classname Otherwise, type will not be able to be resolved.
Why is that? If it is true that a class in package "SimpleGUI.model" is also a class in package "SimpleGUI" (The logic is: package is folder, so "in sub-folder" means "a part of folder" means "a part of package"), "import" shouldn't be necessary.
The BEST user interface design I've ever seen? --- A flush toilet.