Question

The constructor for this enum is private. What does that mean?

public enum SLocale {

    EN_US(Locale.US, "www.abc.com", "www.edc.com", "www.vvv.com",
            "www.earn.com");

    List<String> domains;
    Locale loc;
    IMap map;

    private SLocale(Locale loc, String... domains) {
        this.domains = Arrays.asList(domains);
        this.loc = loc;
        this.siteMap = Factory.getMap(loc);
    }

    public List<String> getDomains() {
        return domains;
    }

    public Locale getLoc() {
        return loc;
    }

    public ISiteMap getMap() {
        return map;
    }
}

Answer 1

A private constructor only allows objects to be constructed from within the class definition. Being an enum, it is easy to get confused, so I usually find it easier to think of an enum as a class with some special features. So when you write:

SLocale.EN_US

Basically, the parameters

Locale.US, "www.abc.com", "www.edc.com", "www.vvv.com", "www.earn.com"

will be passed to the private constructor so that the enum can be instantiated. Enum constructors have to be private.