Hibernate version: 3.2

Hi. I have an invoice table and an invoice-detail table. I have 2 problems:

1) The invoice table has a field called total that is simply the sum of the total of each detail. In my application objects I don't want to have this value, since I can calculate it and avoid inconsistency problems. However, when I insert a new invoice, I have to write this value to the database. I have a getTotal method, but hibernate does not consider it a valid property since it does not have the corresponding setTotal method. Is there a way to map the column and make hibernate get the total from the getTotal method creating this method on the object?

2) There are some other columns in the database I don't want to map. However this columns are declared not null, so I would like to simply fill them with '0'. Is there a way to make hibernate insert a constant to this columns without creating a property for them in the object?

Thanks

I think you could have a look at the formula tag in the mapping. If hibernate is requesting the setTotal but you do not want to provide it publicly, you could define it with protected visibility, Hibernate will still be able to use it. In general, put protected everything you can that's specific to hibernate, but that you would prefer not exposing as a public API.



I guess a formula could do the trick here.

Thanks for your reply.

At first I thought that formula attribute could help me, but I understand that it must be put on a <property> tag and therefore, that requires a name attribute. This means that there must be necessarily a property in the object that maps to the column, and that is what I was trying to avoid.

So far, I solved the problem this way:

For problem 1: I declared a private set that has an empty body. This makes hibernate to recognize the javabean property.

For problem 2: I declared the unused fields as private fields with the constant value and mapped them with field access.

However, I think that this is not an elegant solution. I was hoping that I could solve the issue without touching the objects.

Regards,