For example, as in Java, we can manage the code something like this:
come.xxx.ui
.dialogs
.custome_views
...
.MainFrame
.domain
.Product
...
.exceptions
.UserNotFoundException
...
.utils
...
In this way, it is all clear that which code belongs to which part, on a very large project. But how we can do something like this in C++ to keep the project clean, in a small project it may be no problem, but on a large project, it will be hard to have control on code and classes in one directory.