Summary
A Service Layer is responsible for providing simple and elegant access to application-specific business logic, data access functions, and methods contained in the Data Access Objects and Gateways, and can be used for creating the package Beans.
By calling these sometimes large, complicated methods through the facade pattern of the Service Layer, a simplified interface to the larger underlying code base is made available, providing quick, clean access to the 'important' functions that are required for application development.
This method of application architecture, however basic, will help to reduce the amount of time required to further enhance your application, and will help to ensure that any business-critical logic or SQL statements are kept safe and away from view, only being accessed by the Service Layer and its methods.
Other topics we have covered in this chapter are:
streamlining the API
extending a base class
further code inheritance
