* When enabled, users must authenticate before performing searches.
     */
    @Size(max = 10)
    public String loginRequired;

    /**
     * Enable or disable result collapsing for similar documents.
     * When enabled, similar search results are grouped together.
     */
    @Size(max = 10)
    public String resultCollapsed;

    /**

        existNextPage = startWithOffset < (long) (allPageCount - 1) * (long) pageSize;
        currentPageNumber = start / pageSize + 1;
        if (existNextPage && size() < pageSize) {
            // collapsing
            existNextPage = false;
            allPageCount = currentPageNumber;
        }
        currentStartRecordNumber = allRecordCount != 0 ? start + 1 : 0;

    }
  }

  // Test collapse() a little differently than the rest, as we really want to
  // cover lots of different configurations of input text
  public void testCollapse() {
    // collapsing groups of '-' into '_' or '-'
    doTestCollapse("-", "_");
    doTestCollapse("x-", "x_");
    doTestCollapse("-x", "_x");
    doTestCollapse("--", "_");
    doTestCollapse("x--", "x_");

    }
  }

  // Test collapse() a little differently than the rest, as we really want to
  // cover lots of different configurations of input text
  public void testCollapse() {
    // collapsing groups of '-' into '_' or '-'
    doTestCollapse("-", "_");
    doTestCollapse("x-", "x_");
    doTestCollapse("-x", "_x");
    doTestCollapse("--", "_");
    doTestCollapse("x--", "x_");