private void validateGroupMailbox()

in geronimo-mail_2.1_spec/src/main/java/jakarta/mail/internet/AddressParser.java [1032:1085]
33 lines of code
12 McCabe index (conditional complexity)

    private void validateGroupMailbox(final TokenStream tokens) throws AddressException {
        final AddressToken first = tokens.nextRealToken();
        // is this just a null address in the list?  then push the terminator back and return.
        if (first.type == COMMA || first.type == SEMICOLON) {
            tokens.pushToken(first);
            return;
        }

        // now we need to scan ahead to see if we can determine the type.
        AddressToken token = first;


        // we need to scan forward to figure out what sort of address this is.
        while (first != null) {
            switch (token.type) {
                // until we know the context, these are all just ignored.
                case QUOTED_LITERAL:
                case ATOM:
                    break;

                // a LEFT_ANGLE indicates we have a full RFC822 mailbox form.  The leading phrase
                // is the personal info.  The address is inside the brackets.
                case LEFT_ANGLE:
                    tokens.pushToken(first);
                    validatePhrase(tokens, false);
                    validateRouteAddr(tokens, true);
                    return;

                // we've hit a period as the first non-word token.  This should be part of a local-part
                // of an address.
                case PERIOD:
                // we've hit an "@" as the first non-word token.  This is probably a simple address in
                // the form "user@domain".
                case AT_SIGN:
                    tokens.pushToken(first);
                    validateAddressSpec(tokens);
                    return;

                // reached the end of string...this might be a null address, or one of the very simple name
                // forms used for non-strict RFC822 versions.  Reset, and try that form
                case COMMA:
                // this is the end of the group...handle it like a comma for now.
                case SEMICOLON:
                    tokens.pushToken(first);
                    validateAddressSpec(tokens);
                    return;

                case END_OF_TOKENS:
                    illegalAddress("Missing ';'", token);

            }
            token = tokens.nextRealToken();
        }
    }