Retrieving BLOB objects from DB2 database

[Jennifer Sohl]

Hi there. I have written an app that reads a result set that contains a BLOB object. I have two different questions:

1). Is there anyway that I can automatically determine the file extension of the BLOB object in the database?

2). When I run the java app, it takes a VERY long time for the app to read the BLOB object(s). Can you look at the following code and tell me if I'm doing something wrong?

                                       int fn = 0;
                                                JPanel attPanel = new JPanel();
			while(rs.next()) {
				fn++;
				fileName.replace(0,fileName.length(),"C:\\temp" + fn);
				Blob blob = rs.getBlob(3); 
				InputStream inputStream = blob.getBinaryStream(); 
				File fileOutput = new File(fileName.toString()); 
				FileOutputStream fo = new FileOutputStream(fileOutput); 
				int c; 
				while ((c = inputStream.read()) != -1) 
				fo.write(c); 
				fo.close();
				fileNames.add(fileOutput);
				SKPictureButton spb = new SKPictureButton(url,fileOutput.getName());
				buttons.add(spb);
				spb.addActionListener(this);
                                                                attPanel.insertComponent(spb);
	                                                attPanel.insertComponent(new JLabel("  "));
                                                 }
	
    

Thanks for any help!

[Jeanne Boyarsky]

1) No. If you need this info, you would have to store it in a separate field before you store the file.

2) How long does it take? How big is the file?

[Jennifer Sohl]

Thanks for the reply! The file that I am storing in my table (which is defined as BLOB(5M)) is a .pdf that is only 116K....... it takes about 50 seconds for the information to come up on the screen...... the line of code that seems to be taking a long time is when I call the getBinaryStream() method. Any ideas?

[Jennifer Sohl]

Something else that is also really weird is once the attachment finally shows up in the JTextPane area (as a JButton), the JButton component (Jbutton) is constantly shaking (looks like it is rapidly bouncing up and down)....... anyone ever experienced this behavior before?

[Jeanne Boyarsky]

Jennifer Sohl wrote:Something else that is also really weird is once the attachment finally shows up in the JTextPane area (as a JButton), the JButton component (Jbutton) is constantly shaking (looks like it is rapidly bouncing up and down)....... anyone ever experienced this behavior before?

That sounds like a Swing question. You might want to post it in the Swing forum.

[Jeanne Boyarsky]

Jennifer Sohl wrote:Thanks for the reply! The file that I am storing in my table (which is defined as BLOB(5M)) is a .pdf that is only 116K....... it takes about 50 seconds for the information to come up on the screen...... the line of code that seems to be taking a long time is when I call the getBinaryStream() method. Any ideas?

Is your database on a remote machine? How long does it normally take to download a PDF that size? If you have a dial-up type connection, that sounds about normal.

[Jennifer Sohl]

Hi there! Just wanted to let you know..... I did some more poking around and believe I have resolved the issue....... instead of grabbing the BLOB using InputStream.... I used BufferedInputStream and it popped up lickety split! Thank you so much for all of your help!