What is Building the Analysis Model?

Building the analysis model is the process of defining the structure and behavior of a software system or application at a logical level, primarily focusing on representing the functional requirements identified earlier in the development lifecycle.

According to standard software development practices, the analysis model describes the structure of the system or application that you are modeling. This phase involves translating the 'what' (defined in requirements and use cases) into a more detailed 'how' at a conceptual level, before diving into specific technical implementations.

Components of the Analysis Model

The analysis model provides a static view of the system's elements and a dynamic view of how they interact. It specifically consists of class diagrams and sequence diagrams. These diagrams serve distinct but complementary purposes:

Class Diagrams

• Purpose: Represent the static structure of the system. They show the classes, their attributes, operations, and the relationships between them (like association, aggregation, composition, inheritance).
• In Analysis: Class diagrams in the analysis model typically focus on domain concepts and their relationships, rather than specific technical classes. They capture the essential business objects and their structure.
• Example: A class diagram might show classes like Customer, Order, and Product, defining their properties (e.g., Customer has name, address; Order has date, status) and how they relate (e.g., a Customer places many Orders).

Sequence Diagrams

• Purpose: Represent the dynamic behavior of the system over time, showing how objects interact by sending messages to each other to perform a specific task or use case.
• In Analysis: Sequence diagrams illustrate the flow of control and data for particular use cases. They show the objects involved and the sequence of messages exchanged to achieve the use case's goal.
• Example: A sequence diagram for a "Place Order" use case might show the interaction between a CustomerUI object, a Customer object, an Order object, and a ProductCatalog object, detailing the steps taken to create and submit an order.

Relating to Functional Requirements

These diagrams describe the logical implementation of the functional requirements that you identified in the use case model. The use case model defines what the system should do from the user's perspective. The analysis model takes these requirements and starts to map out how the system's internal components will collaborate logically to fulfill them.

For instance, for a "Process Payment" functional requirement described in a use case, the analysis model would include:

• A class diagram showing classes like Payment, Invoice, CreditCard, and PaymentGateway.
• A sequence diagram illustrating the steps involved when a payment is processed, showing which objects send which messages (e.g., the Order object sending a request to the PaymentGateway object).

Benefits of Building the Analysis Model

Building this model helps in several ways:

• Clarifies Requirements: It forces a deeper understanding of the functional requirements by mapping them to system structure and behavior.
• Facilitates Communication: Provides a clear visual representation for stakeholders, developers, and designers to discuss the system's logic.
• Foundation for Design: Serves as a crucial input for the design phase, where these logical structures and interactions are refined and translated into specific technical designs (e.g., programming languages, database schemas).
• Identifies Complexity: Helps identify potential areas of complexity or ambiguity early in the development process.

In essence, building the analysis model is a critical step in translating high-level requirements into a structured, logical representation of the system's inner workings before detailed design and implementation begin.