RFR: 8009411 : getMethods should not inherit static methods from interfaces

[Peter Levart]

On 09/13/2013 03:38 PM, Joel Borggrén-Franck wrote:
> I fully agree this will most probably occur in practice. But the situation is more complicated for an invoke, since there must have been a A.m() present when C was compiled in order to have an invokeinterface to be there in the first place. Just adding a default to A won't trigger this since there won't be an invokeinterface C.m().
>
> Something like this might do:
>
> Compile A { void m(); }, B {} and C {} together.
> Compile A { } B { static m()} together
> Compile A { default m(); }
>
> Do you have a preference for how we should do this?
>
> cheers
> /Joel

Something like that, yes:

http://cr.openjdk.java.net/~plevart/jdk8-tl/StaticVsDefaultInterfaceMethods/StaticInterfaceMethodInWayOfDefault.java


It shows that VM throws IncompatibleClassChangeError if at invoke time 
the search for method encounters a static method in it's path. Is this 
correct behavior? Should reflection also throw a similar exception? This 
could only be done when requesting a specific method (getMethod(name, 
parameterTypes)), but what to do with getMethods() then?

Running using _v1 classes:
C.m() called
Running using _v2 classes:
Exception in thread "main" java.lang.IncompatibleClassChangeError: 
Expecting non-static method StaticInterfaceMethodInWayOfDefault$B.m()V
     at 
StaticInterfaceMethodInWayOfDefault$TestTask$1.m(StaticInterfaceMethodInWayOfDefault.java)
     at 
StaticInterfaceMethodInWayOfDefault$TestTask.run(StaticInterfaceMethodInWayOfDefault.java:36)
     at 
StaticInterfaceMethodInWayOfDefault.main(StaticInterfaceMethodInWayOfDefault.java:55)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at 
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
     at 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
     at java.lang.reflect.Method.invoke(Method.java:491)
     at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)



Regards, Peter