final Collection<String> values = queryMap.values();
        if (values.stream().anyMatch(s -> s.startsWith(filetypeField))) {
            final ResourceBundle resources = ResourceBundle.getBundle("fess_label", Locale.ENGLISH);
            final String[] fileTypes = ComponentUtil.getFileTypeHelper().getTypes();
            for (final String fileType : fileTypes) {
                final String value = filetypeField + ":" + fileType;

src/main/resources/
├── fess_config.properties     # Main configuration
├── app.xml, fess.xml          # DI configuration
├── fess_*.xml                 # Feature-specific DI
├── fess_label_*.properties    # UI labels (i18n)
├── fess_message_*.properties  # Validation messages (i18n)
└── fess_indices/              # OpenSearch index mappings

src/main/webapp/WEB-INF/view/  # JSP templates