public void btnPreview_actionPerformed(ActionEvent e) {

    DBConn = (PostgresConnector) parent.getDBConn();

    String SQL =
        "SELECT " +
        "(SELECT nama FROM praktek) as nama_praktek, " +
        "(SELECT alamat FROM praktek) as alamat_praktek, " +
        "(SELECT telpon FROM praktek) as telpon_praktek, " +
        "(SELECT kota FROM praktek) as kota_praktek, " +
        "(SELECT propinsi FROM praktek) as propinsi_praktek, " +
        "o.kode_obat, " +
        "o.nama, " +
        "i.keterangan as jenis, " +
        "so.nama as satuan, " +
        "o.harga, " +
        "o.jumlah_tersedia, " +
        "o.keterangan, " +
        "o.batas as batas " +

        "FROM " +
        "obat o, satuan_obat so, item i " +

        "WHERE " +
        "o.satuan = so.id_satuan " +
        "AND o.jenis = i.id_item " +
        "AND o.jumlah_tersedia <= o.batas ";

//    System.out.println(SQL);

    if (cmbKodeAwal.getSelectedIndex() > 0) {
      if (cmbKodeAkhir.getSelectedIndex() > 0) {
        SQL += "AND lower(o.kode_obat) >= '" +
            idObat[cmbKodeAwal.getSelectedIndex() -
            1][0] + "' ";
      }
      else {
        SQL += "AND lower(o.kode_obat) = '" +
            idObat[cmbKodeAwal.getSelectedIndex() -
            1][0] + "' ";

      }
    }

    if (cmbKodeAkhir.getSelectedIndex() > 0) {
      if (cmbKodeAwal.getSelectedIndex() > 0) {
        SQL += "AND lower(o.kode_obat) <= '" +
            idObat[cmbKodeAkhir.getSelectedIndex() -
            1][0] + "'";
      }
      else {
        SQL += "AND lower(o.kode_obat) = '" +
            idObat[cmbKodeAkhir.getSelectedIndex() -
            1][0] + "'";

      }
    }

    if (cmbTipeAwal.getSelectedIndex() > 0) {
      if (cmbTipeAkhir.getSelectedIndex() > 0) {
        SQL += "AND lower(i.id_item) >= '" +
            ( (String) idJenis[cmbTipeAwal.getSelectedIndex() -
             1][0]).toLowerCase() + "' ";
      }
      else {
        SQL += "AND lower(i.id_item) = '" +
            ( (String) idJenis[cmbTipeAwal.getSelectedIndex() -
             1][0]).toLowerCase() + "' ";

      }
    }

    if (cmbTipeAkhir.getSelectedIndex() > 0) {
      if (cmbTipeAwal.getSelectedIndex() > 0) {
        SQL += "AND lower(i.id_item) <= '" +
            ( (String) idJenis[cmbTipeAkhir.getSelectedIndex() -
             1][0]).toLowerCase() + "' ";
      }
      else {
        SQL += "AND lower(i.id_item) = '" +
            ( (String) idJenis[cmbTipeAkhir.getSelectedIndex() -
             1][0]).toLowerCase() + "' ";

      }
    }

    SQL += " ORDER BY o.kode_obat";

    DBConn.query(SQL);

    JRResultSetDataSource resultSetDataSource = new JRResultSetDataSource(
        DBConn.getRs());
    try {
      HashMap hm = new HashMap();
      JasperReport jasperReport = JasperCompileManager.compileReport(
          parent.dirApp + "print" + parent.dirSeparator + "Stok Kritis.jrxml");
      JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, hm,
          resultSetDataSource);

      JasperViewer.viewReport(jasperPrint, false, Locale.getDefault());

    }
    catch (JRException ex) {
      ex.printStackTrace();
    }

  }