*/
    @Size(max = 1000)
    public String sdh;

    /**
     * Parameter to control tracking of total hits in search results.
     */
    @Size(max = 100)
    public String track_total_hits;

    /**
     * Default constructor for SearchForm.
     */
    public SearchForm() {
        super();
    }

    // advance

    @Override
    public int getStartPosition() {