Business Logic Tier

The business logic layer in a three-tier application consists of components that implement business rules, centralizing business logic, and separating it from the user interface and data access. The business logic tier simplifies maintenance and integration of new components.

Components in the business-logic tier are responsible for:

• Ensuring referential integrity by maintaining relations and record sets for a transaction or task.

• Communicating with components in the presentation tier using disconnected record sets. This ensures a clear separation between presentation and application logic. You can implement communication by using Uniface XML stream parameters.

• Encapsulating physical data access via the network by means of the Uniface Router and a set of middleware drivers.

In Uniface, service components handle business logic. Session services handle complex business rules affecting multiple entities. Entity services handle simple business rules for single entities. They are used for strategic reasons in distributed deployment environments that require centralized execution of simple business rules and centralized control of data access.