Are defaults in JDK 8 a form of multiple inheritance in Java?

Question

A new feature coming in JDK 8 allows you to add to an existing interface while preserving binary compatibility.

The syntax is like

public interface S         


        

Answer 1

There are two scenarios:

1) First, that was mentioned, where there is no most specific interface

public interface A {
   default void doStuff(){ /* implementation */ }
}

public interface B {
   default void doStuff() { /* implementation */ } 
}

public class C implements A, B {
// option 1: own implementation
// OR
// option 2: use new syntax to call specific interface or face compilation error
  void doStuff(){
      B.super.doStuff();
  }
}

2) Second, when there IS a more specific interface:

   public interface A {
       default void doStuff() { /* implementation */ } 
    }

    public interface B extends A {
       default void doStuff() { /* implementation */ } 
    }

    public class C implements A, B {
    // will use method from B, as it is "closer" to C
    }