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Mapping issue

rahul khanna
Ranch Hand

Joined: Sep 14, 2005
Posts: 48
I am new to hibernate and not very clear about how mapping works.

I have a 'User' table and a 'Role' table.

User table has fields USERID, USERNAME, ROLEID.

Role table has ROLEID, ROLENAME.

User table has a foreign key reference to the 'ROLE' table (ROLEID).

I am not sure how would the mapping files and the POJO classes would go for both the USER and the ROLE table. Will they have <many-to-one> or <one-to-many> references in the mapping files (which mapping USER or ROLE).

Also, when I do session.load(User.class,userId);
how do i get the ROLE NAME associated with that user.
Just to remind USER table has a ROLE ID and not a ROLE NAME.

Please help with some code snippet for mapping files and the POJO class for the above example

This is urgent!!!

Thanks in advance..
Mark Spritzler
ranger
Sheriff

Joined: Feb 05, 2001
Posts: 17249
    
    6

Well, in your model, Role is the one side and User is the many. So in Role you use a OneToMany mapping to User, and in User you have a ManyToOne mapping to Role.

In your load to get the RoleName, you would probably call getRole from the loaded User class, and the return of that method is a Role object, and call getRoleName from that Role object.

Mark


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rahul khanna
Ranch Hand

Joined: Sep 14, 2005
Posts: 48
Thanks Mark..

I was using Eclipse and figured out a tool 'Hibernate Synchronizer'.

It is a cool thing ..
it generated all the hbm files and the POJO classes for me once mapped to the database..
Mark Spritzler
ranger
Sheriff

Joined: Feb 05, 2001
Posts: 17249
    
    6

Yes, using a tool makes it even easier.

JBoss IDE is Eclipse with JBoss Plugins including very good ones for Hibernate.

Good Luck

Mark
rahul khanna
Ranch Hand

Joined: Sep 14, 2005
Posts: 48
Thanks mark for the prompt reply..
 
I agree. Here's the link: http://aspose.com/file-tools
 
subject: Mapping issue
 
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