I have one question regarding generator. Here is my requirement

1> I have one table which contains one column (say X) which is of string type but which contains only numbers.
2> This column is not an identity or primary key column.
3> Table contains some other primary key columns.
4> the value of X that needs to be generated at the time of saving the object should be like max(integer value of X)+1 , but as i mentioned this is not a numeric column.
5> I m not sure whether i can use the custom generator.

Can anyone give some pointers.

We have several cases like this. We handle them the following way:

1. All of our entities implement a specific interface (which we call IEntity).

2. The IEntity interface defines a property of type IEntityStrategy. The IEntityStrategy interface defines methods SetDefaults() and Validate().

3. Both our implementation of IInterceptor.Instantiate(), and our entity factory (which creates new, transient entity instances) creates and attaches an instance of the appropriate strategy to the entity. When a transient entity is created, its strategy's SetDefaults() method is called. We then code whatever is necessary in SetDefaults() for that entity's strategy.

The strategy classes live in a separate DLL from the entities themselves, and are "persistence aware" (i.e. can execute HQL). If SetDefaults() needs to get some next sequence number, possibly based on some filter like a parent foreign key, by executing some HQL, it can do that.

hi

Ur answer bounce back over my head, i have following property in my mapping file.
Tell me what changes i need to do at mapping level and classes level.
Plz tell me step by step if possible.

<property name="RollupMap" column="RollupMap" type="String" length="5" not-null="false" />