Cannot refer to the static enum field within an initializer?

Don’t “bypass” the error – it won’t do what you want it to. The error is there for good reason.

The enum values are initialized before any other static fields. If you want to do something like adding all the values into a map, do it in a static initializer after everything else:

import java.util.*;

public enum Foo
{
    BAR, BAZ;

    private static final Map<String, Foo> lowerCaseMap;

    static
    {
        lowerCaseMap = new HashMap<String, Foo>();
        for (Foo foo : EnumSet.allOf(Foo.class))
        {
            // Yes, use some appropriate locale in production code :)
            lowerCaseMap.put(foo.name().toLowerCase(), foo);
        }
    }
}