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I've stored a Blob (PNG file) into the database like so:

File file = new File( "image.png" );
FileInputStream fis = new FileInputStream( file );
statement.setBinaryStream( 1, fis, (int) file.length() );

Currently I use this process to get the Blob image from the DB and convert it back into an image for use: 

Blob blob = results.getBlob( 1 );
ImageIcon imageIcon = new ImageIcon( blob.getBytes( 1L, (int) blob.length() ) );

However, i need a method to put the image back into the database (after i've altered it) from the ImageIcon without creating a file, storing it to the disk then reading it back in with the FileInputSteam.

edit for clarity Well, say i've got that image stored inside a Label as an ImageIcon. The only way i know how to put that into the database is to read from a FileInputStream, but that would involve pointlessly making a file of the image. So how would i read the Image from ImageIcon back out as a BinaryStream or Blob back to the database?

VeasMKII
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  • Could you please clarify? Are you unable to use the java object "File", or do you not wish to create another file on the disk? Are you changing the the name of the file when you alter it? Are you saying you can't use a file and FileInputStream to store then read the file, or that you can't use a file to store it, but you need to read it back with the FileInputStream? What, quite frankly, is your question? – MirroredFate Jun 06 '11 at 21:35

2 Answers2

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I'd try something like this

PixelGrabber pg = new PixelGrabber(imageIcon.getImage(),0,0, w,h,true);
pg.grabPixels();
// You may need to wait here until all pixels are copied (see ImageObserver)
Object buffer = pg.getPixels();

See http://download.oracle.com/javase/1.4.2/docs/api/java/awt/image/PixelGrabber.html

You may need to tweak it appropriately and specify correct w and h.

Alex Gitelman
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0

In the Blob API:

setBinaryStream(long pos) returns an OutputStream

"Retrieves a stream that can be used to write to the BLOB value that this Blob object represents." So you can write your bits directly to that stream.

I'm not quite sure how to get the pixels from your modified ImageIcon. If you can cast it to a BufferedImage, that class has a getRGB method.

toto2
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