wrong target (this) in super default method invocation from a lambda

[Peter Levart]

The following code:

package defaulttest;

public class Outer implements K {
    @Override
    public void m() {

        Runnable r = () -> { K.super.m(); };
        r.run();

        K.super.m();
    }

    public static void main(String[] args)
    {
        new Outer().m();
    }
}


in combination with the below interface K also produces the following result:

K.m() this: defaulttest.Outer$1 at 712801c5; Runnable: YES; Outer: NO
K.m() this: defaulttest.Outer at 798c668c; Runnable: NO; Outer: YES


Lambdas are (almost) fully transparent, so this should compile (as opposed to 
anonymous inner classes where it is not supported at the moment).
 

Regards, Peter

On Monday, August 27, 2012 04:30:48 PM Peter Levart wrote:
> While experimenting with current syntax for calling super default methods I
> think I found a bug in b50 compiler. The following example:
> 
> package defaulttest;
> 
> public interface K {
>     void m() default {
>        System.out.println(
>            "K.m() this: " + this +
>            "; Runnable: " + (this instanceof Runnable ? "YES" : "NO") +
>            "; Outer: " + (this instanceof Outer ? "YES" : "NO")
>        );
>     }
> }
> 
> 
> package defaulttest;
> 
> public class Outer implements K {
>     @Override
>     public void m() {
> 
>         new Runnable() {
>             @Override
>             public void run() {
>                 K.super.m();
>             }
>         }.run();
> 
>         K.super.m();
>     }
> 
>     public static void main(String[] args)
>     {
>         new Outer().m();
>     }
> }
> 
> 
> ...prints the following:
> 
> K.m() this: defaulttest.Outer$1 at 798c668c; Runnable: YES; Outer: NO
> K.m() this: defaulttest.Outer at 70a0afab; Runnable: NO; Outer: YES
> 
> 
> The first line indicates that the K.m() default method is invoked, but with
> the wrong target (this) being the instance of the inner Runnable instead of
> Outer.this ...
> 
> 
> Regards, Peter