Application Controller pattern

Description:
The Application Controller design pattern centralizes the request handling by routing incoming requests to appropriate handlers. This pattern is particularly useful for applications with complex request processing logic, as it decouples the request handling from the request processing, promoting modularity and ease of maintenance. Key elements of this pattern include:

1. Application Controller: A central controller that handles incoming requests and delegates them to appropriate handlers.
2. Handlers: Specific components or services that perform the business logic associated with a request.
3. Request: Represents the client request to be processed.
4. Response: Represents the outcome of the request processing, which is sent back to the client.
5. Command: Encapsulates a request as an object, thereby decoupling the sender of a request from its receiver.

References:

• Application Controller Design Pattern
• Project Contribution Guidelines

Acceptance Criteria:

1. Implement the Application Controller class that can route incoming requests to appropriate handlers.
2. Create at least two handler classes demonstrating different business logic processes.
3. Ensure comprehensive unit tests are written to validate the functionality of the Application Controller and handlers.

Review the project contribution guidelines and existing Java design-pattern implementations before defining the Application Controller, handler, request, response, and command boundaries. Done means an Application Controller routes requests to at least two handlers, with comprehensive unit tests covering the controller and handler behavior.