Getting the newly generated uuid value

arashbi · **Joined:** Mon Aug 15, 2005 3:43 am **Posts:** 15

Hi all
Happy new year!
I am using the uuid generated field for a class in my project. I need to get value of the generated value after inserting a new row to the database. Could somebody help me accomplish this please?

Thanks
Arash

farzad · **Posted:** Wed Jan 02, 2008 6:53 pm

arashbi wrote:

Hi all
Happy new year!
I am using the uuid generated field for a class in my project. I need to get value of the generated value after inserting a new row to the database. Could somebody help me accomplish this please?

Thanks
Arash

You will be able to get around this by using @Generated, or its equivalent XML mapping, over the generated field, and after that you will be able to get the generated value from the inserted entity.

Farzad-

arashbi · **Joined:** Mon Aug 15, 2005 3:43 am **Posts:** 15

I am using the same approach, the problem is the field is null after inserting the new entity until you commit the transaction, but I can not commit the transaction at that point; I need to read the generated value before transaction commit

farzad · **Posted:** Thu Jan 03, 2008 1:10 pm

arashbi wrote:

I am using the same approach, the problem is the field is null after inserting the new entity until you commit the transaction, but I can not commit the transaction at that point; I need to read the generated value before transaction commit

Try forcing flush to see if that helps. However, if that's not a solution you may want to call a stored procedure to create a value for you and set the value manually. That's how hibernate handles GUIDs for SQLServer.

Farzad-

gonzao_diaz · **Joined:** Mon Nov 26, 2007 2:29 pm **Posts:** 443

arashbi,

You can use a simple Java class that generates a unique 32-char ID every time it is called, and set the "generator" property of the ID to "assigned".

This simple Java method does that

Code:

    /**
     * returns a unique 32-char ID
     * @return the ID
     */
    public static String getHashableId(){
      String key=new UID().toString();
      key=StringUtils.repeat(key, 3);
      key=key.substring(0, 32);
      key=key.replace(':', '1');
      key=key.replace('-', '2');
      return key;
    }

However, philosophically speaking, the fact that you absolutely need that ID before the object has being committed to the database is troubling. You should not ever need and ID unless it is from a class that had been inserted and has been properly retrieved my means of a query or load. You might want to reconsider your design.