About Question enthuware.ocpjp.v8.2.1878 :

[pavelkubal]

Hi I think, that this question has wrong answer.

the first one is marked as correct anwer, but it doesn't compile

public static double compute(double base, Function<Integer, Integer > func){
return func.apply((int)base);
}

However the third one does compile and is marked as invalid.

[admin]

Are you sure you typed the code as given in the question while trying it out? I tried it just now and option 1 compiles fine.

-Paul.

[henrid]

I already knew that widening and boxing do not go together. But did I just learn today that widening and UNboxing is allowed? This part is not testing Java 8, but okay, nice to know.

[bvrulez]

I wonder if the cast from double to int might pose a problem since the max value of a double is 1.7*10^308 and that of an int is just 2^31-1, and also regarding their minimums.

[admin]

Should be easy to check