*
     * @param key the property key
     * @return map containing the key-value pair
     */
    protected static Map<String, String> createPropItem(final String key) {
        return createItem(key, System.getProperty(key));
    }

    /**
     * Creates a key-value item map for display.
     *
     * @param label the item label
     * @param value the item value

    /**
     * Wraps an object instance into a pooled object.
     * @param obj The object to wrap
     * @return A PooledObject wrapping the given object
     */
    @Override
    public PooledObject<T> wrap(final T obj) {
        return new DefaultPooledObject<>(obj);
    }

    /**
     * Destroys a pooled object and notifies the destroy listener if set.
     * @param p The pooled object to destroy

     *
     * @param message the detail message describing the exception
     * @param cause the cause of this exception
     */
    public FessSystemException(final String message, final Throwable cause) {
        super(message, cause);
    }

    /**
     * Constructs a new FessSystemException with the specified detail message.
     *
     * @param message the detail message describing the exception

    protected int index;

    /**
     * Returns an {@link Iterable} that wraps an {@link IndexedIterator} for use in a for-each statement.
     *
     * @param <T> the element type
     * @param iterable the iterable (must not be {@literal null})
     * @return an {@link Iterable} wrapping an {@link IndexedIterator}
     */
    public static <T> Iterable<Indexed<T>> indexed(final Iterable<T> iterable) {

     * Converts to {@link Double}.
     *
     * @param o
     *            The object to convert
     * @return The converted {@link Double}
     */
    public static Double toDouble(final Object o) {
        return toDouble(o, null);
    }

    /**
     * Converts to {@link Double}.
     *
     * @param o
     *            The object to convert
     * @param pattern
     *            The pattern string

     *
     * @return minimum version
     */
    public int getMinVersion() {
        return minVersion;
    }

    /**
     * Set minimum protocol version
     *
     * @param minVersion minimum version
     */
    public void setMinVersion(int minVersion) {
        this.minVersion = minVersion;
    }

    /**
     * Get maximum protocol version
     *
     * @return maximum version

        final String proxyHost = (String) paramMap.get(Param.Client.PROXY_HOST);
        final String proxyPort = (String) paramMap.get(Param.Client.PROXY_PORT);
        if (StringUtil.isNotBlank(proxyHost) && StringUtil.isNotBlank(proxyPort)) {
            // proxy credentials
            if (paramMap.get(Param.Client.PROXY_USERNAME) != null && paramMap.get(Param.Client.PROXY_PASSWORD) != null) {

    }

    /**
     * Sets the boost value.
     *
     * @param boost the boost value to set
     * @return the query builder
     */
    @Override
    public QueryBuilder boost(final float boost) {
        return queryBuilder.boost(boost);
    }

    /**
     * Applies a filter to the query.
     *
     * @param filter the filter query builder
     * @return the query builder
     */

     *
     * @param url the URL to which the PUT request will be sent
     * @return a new CurlRequest object configured with the PUT method and the specified URL
     */
    public static CurlRequest put(final String url) {
        return new CurlRequest(Method.PUT, url);
    }

    /**
     * Creates a new CurlRequest with the DELETE method for the specified URL.
     *

    /**
     * Sets the language detector.
     *
     * @param detector The language detector.
     */
    public void setDetector(final LanguageDetector detector) {
        this.detector = detector;
    }

    /**
     * Creates a script for updating a document with language information.
     *
     * @param doc The document.
     * @param code The script code.
     * @return The script.
     */