I have done a lot of search but can't find anything related to this topic.

Basically my table looks like this:



My class looks like this:



How should I map the class to the table? Any help is appreciated!

Hibernate doesn't support this. You should either manualy support this (by native SQL) or use dynamic model. With dynamic model your class should looks like this:

Forget about one more way to support this model - using custom value type.

I am thinking about this too. Thanks!

Now I have tried to map a group of columns to an integer array by using CompositeUserType. Most of it is pretty straightforward. But my question is if we can find out the total number of columns that are mapped to the UserType. For now, I have to hardcode the array length in the CompositeUserType class. It means I cannot re-use the class when the array size is different. This shouldn't be hard for Hibernate to provide such information. Hibernate can easily know from the mapping file how many columns are mapped to the UserType and provide it to methods like getPropertyNames and getPropertyTypes.