String type, String subtype, Multimap<String, String> parameters) {
    checkNotNull(type);
    checkNotNull(subtype);
    checkNotNull(parameters);
    String normalizedType = normalizeToken(type);
    String normalizedSubtype = normalizeToken(subtype);
    checkArgument(
        !WILDCARD.equals(normalizedType) || WILDCARD.equals(normalizedSubtype),
        "A wildcard type cannot be used with a non-wildcard subtype");