To explain the Business Delegate pattern, we need to understand some points that show the reason and evidence for the real goals of this pattern. Thus, we will show these points and explain the Business Delegate pattern in detail.
Before we go on, here is a brief explanation of the concept of tiers and layers.
A layer is merely a logical division that has a responsibility within the architecture of the application. It is a logical way to organize the application code. Martin Fowler's book Patterns of Enterprise Application Architecture describes the three main layers and their responsibilities:
Layer | Responsibility |
Presentation | User interaction, validation of input fields, formatting display data |
Business | Application logic |
Data | Database communication, messaging-system communication |
Thus, the classes of an application are logically separated according to their responsibilities. There are classes that are...