ok, default methods in interfaces within in Kotlin...

# announcements

[apatrida]

ok, default methods in interfaces within in Kotlin class heirarchy being called from java can result in AbstractMethodError. So how do you work around this:

Interface Base with method init() in Java. Kotlin extends this with interface MyBase and adds a default implementation of init(). That is extended into MyMegaBase interface which does more. Then finally HappyConcreteClass class implements those and has a base class but does not override the default method. So a call that basically says the following, results in an `AbstractMethodError`:

if (instance instanceof Base) {
  ((Base)instance).init();
}

The default method should be generated into MyMegaBase as the first class that implements the interface, yes? So why the error. (reported as https://youtrack.jetbrains.com/issue/KT-11267, but maybe isn’t a bug, it is just not allowed)