protected Set<String> facetFieldSet;

    /** Array of fields that can be used for sorting search results */
    protected String[] sortFields;

    /** Set of fields that can be used for sorting for O(1) lookup */
    protected Set<String> sortFieldSet;

    /** Set of fields that are allowed in API responses */
    protected Set<String> apiResponseFieldSet;

    /** Set of fields that are not analyzed during indexing */

                    return;
                }
            } else { /* Basic */
                final String auth = new String(Base64.decode(msg.substring(6)), "US-ASCII");
                int index = auth.indexOf(':');
                String user = index != -1 ? auth.substring(0, index) : auth;
                final String password = index != -1 ? auth.substring(index + 1) : "";
                index = user.indexOf('\\');

                    return;
                }
            } else { /* Basic */
                final String auth = new String(Base64.decode(msg.substring(6)), "US-ASCII");
                int index = auth.indexOf(':');
                String user = index != -1 ? auth.substring(0, index) : auth;
                final String password = index != -1 ? auth.substring(index + 1) : "";
                index = user.indexOf('\\');

    /** Constant used to indicate that query-based preference should be used for search routing */
    protected static final String PREFERENCE_QUERY = "_query";

    /** Prefix used to identify sort parameters in search queries */
    protected String sortPrefix = "sort:";

    /** Additional query string to be appended to all search queries */
    protected String additionalQuery;

     *
     * @param userAgent the user agent string to match against directives,
     *                 can be null (treated as empty string)
     * @return the most specific matching directive, or null if no directive matches
     */
    public Directive getMatchedDirective(final String userAgent) {
        final String target;
        if (userAgent == null) {
            target = StringUtil.EMPTY;

#### JSON Search API

**Endpoints**:
- `GET /api/v1/documents?q={query}` (recommended)
- `GET /json/?q={query}` (legacy, for backward compatibility)

**Parameters**:
- `q` - Query string
- `num` - Results per page (default: 20)
- `start` - Starting offset (default: 0)
- `fields.label` - Label filter
- `lang` - Language preference

**Example**:
```bash
# Using the recommended endpoint

     */
    @Size(max = 10)
    public String popularWord;

    /**
     * Character encoding to use for CSV file exports.
     * This setting affects the encoding of downloaded CSV files.
     */
    @Required
    @Size(max = 20)
    public String csvFileEncoding;

    /**
     * Number of days to keep search logs before purging.

<setting id="org.eclipse.jdt.core.formatter.insert_space_after_semicolon_in_for" value="insert"/>
<setting id="org.eclipse.jdt.core.formatter.disabling_tag" value="@formatter:off"/>
<setting id="org.eclipse.jdt.core.formatter.continuation_indentation" value="2"/>
<setting id="org.eclipse.jdt.core.formatter.alignment_for_enum_constants" value="0"/>
<setting id="org.eclipse.jdt.core.formatter.blank_lines_before_imports" value="1"/>

<setting id="org.eclipse.wst.jsdt.core.formatter.insert_space_before_colon_in_case" value="do not insert"/>
<setting id="org.eclipse.wst.jsdt.core.formatter.indent_empty_lines" value="false"/>
<setting id="org.eclipse.wst.jsdt.core.formatter.alignment_for_compact_if" value="16"/>
<setting id="org.eclipse.wst.jsdt.core.formatter.brace_position_for_annotation_type_declaration" value="end_of_line"/>

     * @param defaultValue The default value if the setting is not found.
     * @return The setting value as a String.
     */
    public String getAsString(final String key, final String defaultValue) {
        final Object obj = get(key);

        final String value;
        if (obj == null) {
            value = defaultValue;
        } else {
            value = obj.toString();
        }