Why “final static int” can be used as a switch's case constant but not “final static ”

Question

Why is this int switch valid:

public class Foo {
    private final static int ONE = 1;
    private final static int TWO = 2;

    public static void main(String         


        

Answer 1

I had a similar requirement and worked around this problem by switching on the Enums ordinal number instead of switching on the enum itself. This is not very beautiful/intuitive but it works:

public class Foo {

    private final static int SRC = 0; // == RetentionPolicy.SOURCE.ordinal();
    private final static int RT = 2; // == RetentionPolicy.RUNTIME.ordinal();

    static{
        if (RT != RetentionPolicy.RUNTIME.ordinal() || SRC !=  RetentionPolicy.SOURCE.ordinal()) {
            throw new IllegalStateException("Incompatible RetentionPolicy.class file");
        }
    }

    public static void main(String[] args) {
        RetentionPolicy value = RetentionPolicy.RUNTIME;
        switch (value.ordinal()) {
            case RT: break;
            case SRC: break;
        }
    }

}

Note that it is of course not possible to declare the constant as e.g.

private final static int SRC = RetentionPolicy.SOURCE.ordinal();

for the same reason one is not able to declare the constant as an Enum in the first place...