OCP Java SE 6 Practice Questions - WeatherTest Enum

Question

A question in "OCP Java SE 6 Programmer Practice Exams (Exam 310-065)" Assesment test 2.

Given:

public class WeatherTest {
static Weather w;

public static void main(String[] args) {
    System.out.print(w.RAINY.count + " " + w.Sunny.count + " ");
}

enum Weather {
    RAINY, Sunny;
    int count = 0;

    Weather() {
        System.out.print("c ");
        count++;
    }
}
}

What is the result?

A. c 1 c 1

B. c 1 c 2

C. c c 1 1

D. c c 1 2

E. c c 2 2

F. Compilation fails.

G. An exception is thrown at runtime.

The answer the book says C.

But when I try running this code I get compilation error, saying "The static field WeatherTest.Weather.RAINY should be accessed in a static way".

Which is correct and expected, but no one has complained about it on internet, so I am wondering if I am missing something? Has it got something to do with Java version or something?

Answer 1

The code compiles and gives answer C.

All that is happening is that your IDE is issuing you with a warning that you should not access static members on an instance of a class, as it it confusing. w.RAINY makes it look like RAINY is an instance field, when in fact it is static. In this case w is actually null. The usual way to access static members is to use ClassName.member. Here you should write Weather.RAINY.