How to "serialize to" and "retrieve from" objects from hsqldb

Assuming ChartData implements the serializable interface:

     String insertGraph ="INSERT INTO GRAFICI_BLOB (ID, DATA) VALUES (##, ?)"

    ChartData chartData = chartsPage.getChartData();
     // Serialize to a byte array
     ByteArrayOutputStream bos = new ByteArrayOutputStream();
     try {
         ObjectOutputStream out = new ObjectOutputStream(bos);
         out.writeObject(chartData);
         out.close();
     } catch (IOException e2) {
         e2.printStackTrace();
     }
     byte[] chartDataBytes = bos.toByteArray();

     PreparedStatement str1 = null;
     try {
         str1 = con.prepareStatement(insertGraph);
         str1.setBytes(1, chartDataBytes);
         str1.executeUpdate();
     } catch (Exception ex) {
         ex.printStackTrace();
     } finally {
         try {
             if (null != str1)
                 str1.close();
         } catch (Exception ex) {
         }

     }

/*
* and the way back
*/
          Statement stmt = con.createStatement();
          String sql = the query to select your blob field... (in my case GRAFICO)

          ResultSet res = stmt.executeQuery(sql);
          byte[] bytes = res0.getBytes("GRAFICO");
              // Deserialize from byte array
              try {
                  ObjectInputStream in = new ObjectInputStream(new ByteArrayInputStream(bytes));
                  runProperties.chartData = (ChartData) in.readObject();
                  in.close();
              } catch (IOException e) {
                  e.printStackTrace();
              } catch (ClassNotFoundException e) {
                  e.printStackTrace();
              }

How to insert and retrieve files in hsqldb

How to save files into hsqldb? How to restore them back?

     String calibrationZip = "calibrazione.zip";
     String newcalibrationZip = "new_calibrazione.zip";
      String insertStr = "INSERT INTO CALIBRAZIONE_BLOB (ID, DATA) VALUES (##, ?)"
     String sql = "select data as DATA from CALIBRAZIONE_BLOB where id = ##"
      int runId = 1;


     /*
      * insert into blob
      */
     FileInputStream fis = null;
     PreparedStatement st = null;
     try {
         File fl = new File(calibrationZip);
         fis = new FileInputStream(fl);
         insertStr = insertStr.replaceFirst("##", String.valueOf(runId));
         st = con.prepareStatement(insertStr);
         st.setBinaryStream(1, fis, (int) fl.length());
         st.executeUpdate();
     } catch (Exception ex) {
         System.out.println(ex);
     } finally {
         try {
             if (null != st)
                 st.close();
         } catch (Exception ex) {
         }
         try {
             if (null != fis)
                 fis.close();
         } catch (Exception ex) {
         }
     }

     /*
      * extract the blob
      */
     sql = sql.replaceFirst("##", String.valueOf(runId));
     try {
         Statement statement = con.createStatement();
         ResultSet rs = statement.executeQuery(sql);
         if (rs.next()) {
             InputStream is = rs.getBinaryStream("DATA");
             FileOutputStream fos = new FileOutputStream(newcalibrationZip);
             byte[] buff = new byte[8192];
             int len;
             while( 0 < (len = is.read(buff)) )
                 fos.write(buff, 0, len);
             fos.close();
             is.close();
         }
         rs.close();
         statement.close();
     } catch (FileNotFoundException e) {
         e.printStackTrace();
     } catch (SQLException e) {
         e.printStackTrace();
     } catch (IOException e) {
         e.printStackTrace();
     }