You can use custom business object handlers with the BAPI module. Reasons for choosing to write custom business object handlers include the following:
There are two ways to create custom business object handlers: modifying a generated business object handler or writing a business object handler from scratch.
SAP ODA by default generates business object handlers when you generate business objects. In addition to compiled class files, the ODA generates Java source files for the business object handlers. You can customize the generated Java source and create with your own business object handler.
Although writing your own business object handler is not recommended, if you follow this approach, use the generated business object handler as a template since it provides calls to utility methods.