This is a very general question so it's difficult to give a specific answer, you might want to consider the following as guidance though:
- Design a domain object/model to hold whatever data you are reading from the xls file. Your read method should return a list of this object.
- Create a Spring manager class to act as your service layer, this might have a method called save which takes a list of objects from step one.
- Create a data access object which handles the mapping of objects passed through from step two. You might consider using an ORM tool (Hibernate for example) for this step.
I hope this points you in the right direction.