Java: Importing resources, the use of "*"?

I am currently working on a tutorial that uses the following imports:

//importing Resources
import java.awt.*;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.*;

My question is: does java.awt.* import everything from awt? And if so why is this necessary?

 import java.awt.event.ItemEvent;

My question is: does java.awt.* import everything from awt?

It imports all the classes in java.awt, but that's all.

And if so why is this necessary?
import java.awt.event.ItemEvent; 

Because that's not in java.awt - it's in java.awt.event. Packages in Java aren't really hierarchical, even though they look that way. As far as the Java language is concerned, java.awt and java.awt.event are entirely separate packages.

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