private static final long serialVersionUID = 1L;

    private final LruHashMap<E, Object> map;

    // Dummy value to associate with an Object in the backing Map
    private static final Object PRESENT = new Object();

    public LruHashSet(final int limitSize) {
        map = new LruHashMap<>(limitSize);
    }

    /**

    /** The key of the configuration. e.g. 3600 */
    String COOKIE_DEFAULT_EXPIRE = "cookie.default.expire";

    /** The key of the configuration. e.g. cookie */
    String SESSION_TRACKING_MODES = "session.tracking.modes";

    /** The key of the configuration. e.g. 25 */
    String PAGING_PAGE_SIZE = "paging.page.size";

    /** The key of the configuration. e.g. 5 */