Re: Displaying/Pulling Images using JDBC ... - Mailing list pgsql-jdbc

I am attaching a JDBC patch that is about to be applied for 7.2.
Perhaps this fixes the problem because it deals with BLOBS.


> Hi Marc,
>
> I seem to be having the same problem as you when trying to insert
> audio files into the database. They are inserted OK using
> PreparedStatement.setBinaryStream(), but the data is truncated
> when retrieved using PreparedStatement.getBinaryStream().
> This occurs using the jdbc7.1beta5 driver.
>
> Interestingly, when I try to use an older JDBC driver (jdbc7.1beta4), it
> manages to correctly read back the object stored by the jdbc7.1beta5 driver.
> However, the jdbc7.1beta4 driver itself can't write the large object to the
> database. It keeps throwing an exception:    InputStream as parameter not
> supported.
>
> Can you let me know if you find out the cause of the problem, or
> better still a solution?
>
> Thanks,
> Khanh Ho.
>
>
> > -----Original Message-----
> > From: The Hermit Hacker [mailto:scrappy@hub.org]
> > Sent: Sunday, 13 May 2001 2:45 AM
> > To: pgsql-jdbc@postgresql.org
> > Cc: peter@retep.org.uk
> > Subject: [JDBC] Displaying/Pulling Images using JDBC ...
> >
> >
> >
> >
> > Morning folks ...
> >
> >     Been wracking our brains on this one for too long now ... have a
> > client that is trying to use JDBC to pull images stored in
> > the database,
> > and, from what we can gather, the images are coming out
> > 'truncated' ...
> >
> >     If the client stores the images as ASCII (uuencoded) and pulls
> > those out, all works well, but if he stores them as
> > binary/raw images, the
> > images don't come out ...
> >
> >     If he retrieves that image using psql and stores it to a file,
> > that file is fine, so apparently the backend is storing it
> > properly ...
> >
> >     According to the table schema that we have, the image is being
> > stored as an 'oid' type ...
> >
> >         In relation to the image settings, they are counting the bytes
> > that the stream is going to send to the client and verifying it on the
> > clients side, the numbers are not matching unless it is an ascii based
> > file....
> >
> >     Both the backend server and the JDBC drivers are v7.1 ...
> >
> >     Now, my thought on this is that it *sounds* like the JDBC is
> > hitting some sort of control character is the stream that
> > tells it to stop
> > sending the image ... is this possible?  Some binary
> > character that needs
> > to somehow be trapped?
> >
> >     Image content is a mostly a faxed document saved as .tif format.
> > But it could be anything and we derive it from the file name.
> >  We upload
> > the document to the database.  Please See the source
> >
> >     Sample of the source they are using is as follows, is
> > there something
> > that we are seeing:
> >
> > PreparedStatement prepStmt = con.prepareStatement(selectstatement);
> > prepStmt.setString(1, medicalRecordId);
> > ResultSet rs = prepStmt.executeQuery();
> > if (rs.next()) {
> >   medicalRecordId = rs.getString(1);
> >   typeSOAP = rs.getString(2);
> >   code = rs.getString(3);
> >   String datetimetemp = rs.getString(4);
> >   datetime = Timestamp.valueOf(datetimetemp);
> >   testObject = rs.getString(5);
> >   testResult = rs.getString(6);
> >   note = rs.getString(7);
> >   appointmentId = rs.getString(8);
> >   patientId = rs.getString(9);
> >   test = rs.getString(10);
> >   category = rs.getString(11);
> >
> >   //if(imageName == null){
> >   if(imageNametemp != null){
> >      imageName = rs.getString(12);
> >
> >
> >      BufferedInputStream bis = new
> > BufferedInputStream(rs.getBinaryStream(13));
> >      System.out.println("value of bis"+bis.toString());
> >      //InputStream is = rs.getBinaryStream(13);
> >
> >      //System.out.println("vale of inputstream"+is.toString());
> >
> >      int TotLen=0;
> >
> >      ByteArrayOutputStream imageOutputStream = new
> > ByteArrayOutputStream(8164);
> >
> >      byte[] b = new byte[8164];
> >      int len=0;
> >
> >      try {
> >        while( (len = bis.read(b,0,8164)) != -1 ) {
> >          imageOutputStream.write(b,0,len);
> >
> >          TotLen += len;
> >        }
> >        bis.close();
> >        imageAsBytes = imageOutputStream.toByteArray();
> >
> >        System.out.println("value of baoslenght"+imageAsBytes.length);
> >        System.out.println("value of totlenght"+TotLen);
> >
> >        System.out.println("vale of
> > baos"+imageOutputStream.toString());
> >      }
> >      catch(IOException e) {
> >      }
> >   }
> >     prepStmt.close();
> >
> >
> > Marc G. Fournier                   ICQ#7615664
> > IRC Nick: Scrappy
> > Systems Administrator @ hub.org
> > primary: scrappy@hub.org           secondary:
> > scrappy@{freebsd|postgresql}.org
> >
> >
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