// interfaces/SealedInterface.java // (c)2021 MindView LLC: see Copyright.txt // We make no guarantees that this code is fit for any purpose. // Visit http://OnJava8.com for more book information. // {NewFeature} Since JDK 17 sealed interface Ifc permits Imp1, Imp2 {} final class Imp1 implements Ifc {} final class Imp2 implements Ifc {} sealed abstract class AC permits X {} final class X extends AC {}