Duplicating a record

nalla_vinay · **Posted:** Sat May 10, 2008 3:13 am

Hi,

I have following Objects:

1) EventDb
2) ContactInfo
3) KeynoteInfo etc

there is parent child relationship from Event --> ContactInfo, KeynoteInfo.

Code:

public class EventDb  implements java.io.Serializable {


     private String genericEventId;
     private EventDb eventDb;
     private String eventName;
     private String eventYear;
     .......     
    
     private List<ContactInfo> contactInfos = new ArrayList<ContactInfo>(0);
    
   private List<KeynoteInfo> keynoteInfos = new ArrayList<KeynoteInfo>(0);

// other childs...

    public EventDb() {
    }

   // code......


public class ContactInfo  implements java.io.Serializable {


     private String contactId;
     private EventDb eventDb;    
     private String contactName;   
     private Character isDuplicated;
     .......

    public ContactInfo() {
    }

// remaining code..

same way KeynoteInfo POJO.

My requirement:

I need to duplicate the data of selected EventDb and its childs as a new record in the database.

please tell me how to do this duplicate operation.

thanks in advance.

kcbhiber · **Joined:** Sat May 10, 2008 6:13 pm **Posts:** 1

i do not know if there is any better way...
once you have selected the object graph for the EventDB, set the primary key id to 0 on each of the objects in the graph and save(persist) it so that you will have a duplicate record. You need to make the set methods for the primary key id as public.

sagimann · **Joined:** Sun Jun 11, 2006 10:41 am **Posts:** 164

Hi,
I see that the child objects also have their own IDs, which means they are stored within their own table, correct?
What you need is a "deep cloning" procedure that can pick up any one of your entities and clone it with any relevant information in it.

Am I correct?
If so, I've done something similar in a recent project. There are several design solutions. A simple one:

Implement some 'clone' method in all your entities, that performs deep-cloning. You may create different variations, i.e. cloneForInsert, cloneForSelect, each clones a different set of properties.

I have some other more "exotic" ideas which I have used for very complex entity graphs, but the above is usually ok for most cases.

nalla_vinay · **Posted:** Thu May 15, 2008 4:22 am

Hi sagimann,

I also got the same idea after going through few post in forum,
instead of cloning method i've tried using copy constructor, which is working fine.

Thanks sagimann & kcbhiber for your suggestions.

Regards
Vinay