public static Validator<CharSequence> domainName(@NonNull final Context context) {
        return new DomainNameValidator(context, R.string.default_error_message);
    }
public static Validator < CharSequence > domainName ( @ NonNull final Context context ) { return new DomainNameValidator ( context , R . string . default_error_message ) ; }
Creates and returns a validator, which allows to validate texts to ensure, that they
represent valid domain names. Empty texts are also accepted.

@param context
The context, which should be used to retrieve the error message, as an instance of
the class {@link Context}. The context may not be null
@return The validator, which has been created, as an instance of the type {@link Validator}