public static Map splitKv()

in inlong-common/src/main/java/org/apache/inlong/common/util/StringUtil.java [56:164]
98 lines of code
28 McCabe index (conditional complexity)

    public static Map<String, String> splitKv(
            @Nonnull String text,
            @Nonnull Character entryDelimiter,
            @Nonnull Character kvDelimiter,
            @Nullable Character escapeChar,
            @Nullable Character quoteChar) {
        Map<String, String> fields = new HashMap<>();

        StringBuilder stringBuilder = new StringBuilder();

        String key = "";
        String value;

        int state = STATE_KEY;

        /*
         * The state when entering escaping and quoting. When we exit escaping or quoting, we should restore this state.
         */
        int kvState = STATE_KEY;

        for (int i = 0; i < text.length(); ++i) {
            char ch = text.charAt(i);

            if (ch == kvDelimiter) {
                switch (state) {
                    case STATE_KEY:
                        key = stringBuilder.toString();
                        stringBuilder.setLength(0);
                        state = STATE_VALUE;
                        break;
                    case STATE_VALUE:
                        throw new IllegalArgumentException("Unexpected token " + ch + " at position " + i + ".");
                    case STATE_ESCAPING:
                        stringBuilder.append(ch);
                        state = kvState;
                        break;
                    case STATE_QUOTING:
                        stringBuilder.append(ch);
                        break;
                }
            } else if (ch == entryDelimiter) {
                switch (state) {
                    case STATE_KEY:
                        throw new IllegalArgumentException("Unexpected token " + ch + " at position " + i + ".");
                    case STATE_VALUE:
                        value = stringBuilder.toString();
                        fields.put(key, value);

                        stringBuilder.setLength(0);
                        state = STATE_KEY;
                        break;
                    case STATE_ESCAPING:
                        stringBuilder.append(ch);
                        state = kvState;
                        break;
                    case STATE_QUOTING:
                        stringBuilder.append(ch);
                        break;
                }
            } else if (escapeChar != null && ch == escapeChar) {
                switch (state) {
                    case STATE_KEY:
                    case STATE_VALUE:
                        kvState = state;
                        state = STATE_ESCAPING;
                        break;
                    case STATE_ESCAPING:
                        stringBuilder.append(ch);
                        state = kvState;
                        break;
                    case STATE_QUOTING:
                        stringBuilder.append(ch);
                        break;
                }
            } else if (quoteChar != null && ch == quoteChar) {
                switch (state) {
                    case STATE_KEY:
                    case STATE_VALUE:
                        kvState = state;
                        state = STATE_QUOTING;
                        break;
                    case STATE_ESCAPING:
                        stringBuilder.append(ch);
                        state = kvState;
                        break;
                    case STATE_QUOTING:
                        state = kvState;
                        break;
                }
            } else {
                stringBuilder.append(ch);
            }
        }

        switch (state) {
            case STATE_KEY:
                throw new IllegalArgumentException("Dangling key.");
            case STATE_VALUE:
                value = stringBuilder.toString();
                fields.put(key, value);
                return fields;
            case STATE_ESCAPING:
                throw new IllegalArgumentException("Not closed escaping.");
            case STATE_QUOTING:
                throw new IllegalArgumentException("Not closed quoting.");
            default:
                throw new IllegalStateException();
        }
    }