Hi, I have two classes, lets call them Parent and Child. In some cases I make an instance of only Parent. In another case I make an instance of Child which inherits Parent. What I want to know how ...

Sealed classes, proposed in JEP 409 and available since Java 17, let developers limit and control how deeply a component's type hierarchy can extend. With sealed classes, a developer can essentially ...

parent class's method must be able to call the next m in the list. It may be irritating to have a child class's method signature be constrained by a parent class's method signature. Suppose a parent ...