static List parse()

in tapestry-core/src/main/java/org/apache/tapestry5/internal/services/FieldValidatorSourceImpl.java [277:418]
95 lines of code
21 McCabe index (conditional complexity)

    static List<ValidatorSpecification> parse(String specification)
    {
        List<ValidatorSpecification> result = newList();

        char[] input = specification.toCharArray();

        int cursor = 0;
        int start = -1;

        String type = null;
        boolean skipWhitespace = true;
        State state = State.TYPE_START;

        while (cursor < input.length)
        {
            char ch = input[cursor];

            if (skipWhitespace && Character.isWhitespace(ch))
            {
                cursor++;
                continue;
            }

            skipWhitespace = false;

            switch (state)
            {

                case TYPE_START:

                    if (Character.isLetter(ch))
                    {
                        start = cursor;
                        state = State.TYPE_END;
                        break;
                    }

                    parseError(cursor, specification);

                case TYPE_END:

                    if (Character.isLetter(ch))
                    {
                        break;
                    }

                    type = specification.substring(start, cursor);

                    skipWhitespace = true;
                    state = State.EQUALS_OR_COMMA;
                    continue;

                case EQUALS_OR_COMMA:

                    if (ch == '=')
                    {
                        skipWhitespace = true;
                        state = State.VALUE_START;
                        break;
                    }

                    if (ch == ',')
                    {
                        result.add(new ValidatorSpecification(type));
                        type = null;
                        state = State.COMMA;
                        continue;
                    }

                    parseError(cursor, specification);

                case VALUE_START:

                    start = cursor;
                    state = State.VALUE_END;
                    break;

                case VALUE_END:

                    // The value ends when we hit whitespace or a comma

                    if (Character.isWhitespace(ch) || ch == ',')
                    {
                        String value = specification.substring(start, cursor);

                        result.add(new ValidatorSpecification(type, value));
                        type = null;

                        skipWhitespace = true;
                        state = State.COMMA;
                        continue;
                    }

                    break;

                case COMMA:

                    if (ch == ',')
                    {
                        skipWhitespace = true;
                        state = State.TYPE_START;
                        break;
                    }

                    parseError(cursor, specification);
            } // case

            cursor++;
        } // while

        // cursor is now one character past end of string.
        // Cleanup whatever state we were in the middle of.

        switch (state)
        {
            case TYPE_END:

                type = specification.substring(start);

            case EQUALS_OR_COMMA:

                result.add(new ValidatorSpecification(type));
                break;

            // Case when the specification ends with an equals sign.

            case VALUE_START:
                result.add(new ValidatorSpecification(type, ""));
                break;

            case VALUE_END:

                result.add(new ValidatorSpecification(type, specification.substring(start)));
                break;

            // For better or worse, ending the string with a comma is valid.

            default:
        }

        return result;
    }