Today, I updated my Java version from 16 to 17, and I found that sealed classes is a new feature in it. I think it can be declared like this: public sealed class Main permits AClass, AnotherClass {...

Today I created a small test project for java 16 preview. I created a sealed interface and a final implementation. I want to know if there is anyway to be able to mock the sealed interface so that ...

I have the following sealed interface (Java 15): public sealed interface Animal permits Cat, Duck { String makeSound(); } This interface is implemented by 2 classes: public final class Cat imple...

Sealed classes and sealed interfaces were a preview feature in Java 15, with a second preview in Java 16, and now proposed delivery in Java 17. They have provided classic examples like Shape -> ...

I don't really understand why there is a non-sealed keyword in JEP-360 / Java 15. For me, an extension of a sealed-class should only be final or a sealed-class itself. Providing the non-sealed keyw...

I have a parent abstract class and child classes which take generics. public abstract sealed class Parent<T> permits ChildA, ChildB {} public non-sealed class ChildA<T extends FileTypeA&g...

As we know Java 16 brings with a new features like Records, sealed interfaces and classes, and also pattern matching. Today I wanted use them in my training project. However, I ran into a problem, ...

I have a simple sealed class, MyShape: public sealed class MyShape permits MyCircle { private final int width; private final int height; public MyShape(int width, int height) { this.width = w...