static IntRange jTable_visibleRows(JTable table) {
  ret table == null ? null : swing(func -> IntRange { 
    Rectangle vr = table.getVisibleRect();
    int firstVisibleRow = table.rowAtPoint(vr.getLocation());
    vr.translate(0, vr.height);
    ret intRange(firstVisibleRow, table.rowAtPoint(vr.getLocation())+1);
  });
}