Nested classes are classes that are declared as members of other classes or scopes. Nesting classes is one way to better organize your code. For example, say you have a non-nested class (also known as ...

The release of Java SE 15 in Sept 2020 will introduce "sealed classes" (JEP 360) as a preview feature. A sealed class is a class or interface which restricts which other classes or interfaces may ...

Although the snooze button is probably the most commonly used button on an alarm clock, even a simple AlarmClock class needs a few more features. For instance, you might want to control how long the ...