updating an image into database Blob field

satheesh · **Joined:** Wed Sep 15, 2004 6:56 am **Posts:** 1

Hi all
I am a new user of Hibernate I am using the hibernate-2.1 version
i am able to map all the column in the db and also can retrive the image
but a problem of updating an image inyo db for I used the seession.update method,but the image is not updated rest of the fields are updated.session=openSession();
Blob b1 = Hibernate.createBlob(picc);
Transaction t = session.beginTransaction();
PatientFinding pfgs = (PatientFinding)session.load(PatientFinding.class,fdi);

pfgs.setFindingsText(finding);
pfgs.setLastUpdatedDate(d);
pfgs.setFindingsImage(b1);
session.update(pfgs);
t.commit();
session.close();

in the above code picc is a byte array
is there is any thing wrong?
if any body know the answer please help me,if possible please give the correct code for inserting the image,and is there any change in the mapping file
I had generated it using middlegen.

mapacho · **Joined:** Thu Jan 11, 2007 1:57 pm **Posts:** 9

hi!
i have the same problem. did you fixed it? i have tried but it does not work. hibernate persist the image but if i update the entity encapsulating the image, all other properties become updated but not the image. i set cascade for all actions (persist, merge, refresh and remove).

please, help!

Satyendra · **Joined:** Thu Jan 24, 2008 1:24 am **Posts:** 3

could you send me your code for displaying image in jsp so that i can solve your problem.

ysbelman · **Joined:** Thu Oct 25, 2007 5:24 pm **Posts:** 12

fast forward to Nov 2008 and Hibernate 3.2, I'm unable to update the blob as well. No problems inserting new rows with blob images.

Code:

@Column(name="MIME_TYPE", length=35, nullable=false)
private String mimeType;
   
@Lob // 500Kb
@Column(name="IMAGE", length=510000, nullable=false)
private Blob image;
   
@Lob //30kb
@Column(name="THUMBNAIL", length=30000, nullable=false)
private Blob thumbNail;

here's how i set the blobs from an incoming MultipartFile

Code:

MyImageEntity(org.springframework.web.multipart.MultipartFile image){
 InputStream sourceStream = image.getInputStream();
 ByteArrayOutputStream out = new ByteArrayOutputStream();
 ImageUtil.resize(400, "JPEG", sourceStream, out);
 byte[] resizedBytes = out.toByteArray();
 image = Hibernate.createBlob(resizedBytes);
      
 ByteArrayInputStream resizedByes2 = new  ByteArrayInputStream(resizedBytes);
 out = new ByteArrayOutputStream();
 ImageUtil.resize(100, "JPEG", resizedByes2, out);
 thumbNail = Hibernate.createBlob(out.toByteArray());

Why won't hibernate update the blob itself with update() or merge() ? Other columns do get updated however (mimeType for example)

Mikee805 · **Posted:** Mon Jan 12, 2009 7:23 pm

I am having a simial problem. I have a list of blobs:

@CollectionOfElements(fetch=FetchType.LAZY)
public List<Blob> extendedKeystrokeDataPerm;

I set the list of the blobs but when I update the object nothing is saved.

Any help would be great appreciated.

Thanks,
Mike

ysbelman · **Joined:** Thu Oct 25, 2007 5:24 pm **Posts:** 12

I ended up having to delete the entity and create new one. I'm sure that's what you wanted to hear :)

Mikee805 · **Posted:** Tue Jan 13, 2009 2:52 pm

Quote:

I ended up having to delete the entity and create new one. I'm sure that's what you wanted to hear :)

Yeah, thats exactly the solution I was hoping for.

Thanks for replying!

cbredesen · **Posted:** Tue Jan 13, 2009 5:26 pm

It's important to understand what a BLOB is. It's not a typical database column, it's more or less a pointer to binary data that is read from and written to using streams. Look at the methods:

http://java.sun.com/j2se/1.5.0/docs/api ... /Blob.html

On most databases (all?) you can only use these methods inside the boundaries of a transaction.