static int findTemplatePathSettingAssignmentsStart()

in freemarker-javax-servlet/src/main/java/freemarker/ext/servlet/InitParamParser.java [178:252]
57 lines of code
28 McCabe index (conditional complexity)

    static int findTemplatePathSettingAssignmentsStart(String s) {
        int pos = s.length() - 1;
        
        // Skip WS
        while (pos >= 0 && Character.isWhitespace(s.charAt(pos))) {
            pos--;
        }
        
        // Skip `)`
        if (pos < 0 || s.charAt(pos) != ')') return -1;
        pos--;
        
        // Skip `(...`
        int parLevel = 1;
        int mode = 0;
        while (parLevel > 0) {
            if (pos < 0) return -1;
            char c = s.charAt(pos);
            switch (mode) {
            case 0:  // 0: outside string literal
                switch (c) {
                case '(': parLevel--; break;
                case ')': parLevel++; break;
                case '\'': mode = 1; break;
                case '"': mode = 2; break;
                }
                break;
            case 1:  // 1: inside '...'
                if (c == '\'' && !(pos > 0 && s.charAt(pos - 1) == '\\')) {
                    mode = 0;
                }
                break;
            case 2:  // 2: inside "..."
                if (c == '"' && !(pos > 0 && s.charAt(pos - 1) == '\\')) {
                    mode = 0;
                }
                break;
            }
            pos--;
        }

        // Skip WS
        while (pos >= 0 && Character.isWhitespace(s.charAt(pos))) {
            pos--;
        }
        
        int biNameEnd = pos + 1;
        
        // Skip name chars
        while (pos >= 0 && Character.isJavaIdentifierPart(s.charAt(pos))) {
            pos--;
        }
        
        int biNameStart = pos + 1;
        if (biNameStart == biNameEnd) {
            return -1;
        }
        String biName = s.substring(biNameStart, biNameEnd);
        
        // Skip WS
        while (pos >= 0 && Character.isWhitespace(s.charAt(pos))) {
            pos--;
        }
        
        // Skip `?`
        if (pos < 0 || s.charAt(pos) != '?') return -1;
        
        if (!biName.equals(TEMPLATE_PATH_SETTINGS_BI_NAME)) {
            throw new TemplatePathParsingException(
                    StringUtil.jQuote(biName) + " is unexpected after the \"?\". "
                    + "Expected \"" + TEMPLATE_PATH_SETTINGS_BI_NAME + "\".");
        }
        
        return pos;
    }