tailieunhanh - Bài Giảng Phân tích thiết kế hướng đối tượng (phần 4)

Tham khảo tài liệu 'bài giảng phân tích thiết kế hướng đối tượng (phần 4)', công nghệ thông tin, kỹ thuật lập trình phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Contracts and UML interaction diagrams Lecture 4 Hoa Sen University Agenda System sequence diagram Operation Contract On to Object design Interaction diagrams Sequence diagrams Communication diagrams Hoa Sen University System Sequence Diagram Hoa Sen University What is System Sequence Diagram A diagram that shows, for ONE particular scenario of a use case, the events that external actors generate, their order, and INTER-system events. (not detailed method calls between objects) Describe what a system does without explaining why Hoa Sen University System sequence diagram Hoa Sen University Use Cases and SSDs Hoa Sen University Choosing events and operation name System events should be expressed at the abstract level of intention rather than in terms of the physical input device Hoa Sen University Iterative and Evolutionary SSDs Do not create SSDs for all scenarios (remember agile style) SSDs are part of the Use-Case Model Visualization of the interactions . | Contracts and UML interaction diagrams Lecture 4 Hoa Sen University Agenda System sequence diagram Operation Contract On to Object design Interaction diagrams Sequence diagrams Communication diagrams Hoa Sen University System Sequence Diagram Hoa Sen University What is System Sequence Diagram A diagram that shows, for ONE particular scenario of a use case, the events that external actors generate, their order, and INTER-system events. (not detailed method calls between objects) Describe what a system does without explaining why Hoa Sen University System sequence diagram Hoa Sen University Use Cases and SSDs Hoa Sen University Choosing events and operation name System events should be expressed at the abstract level of intention rather than in terms of the physical input device Hoa Sen University Iterative and Evolutionary SSDs Do not create SSDs for all scenarios (remember agile style) SSDs are part of the Use-Case Model Visualization of the interactions implied in the use cases scenarios Hoa Sen University Operation Contract Hoa Sen University Example Contract Contract CO2: enterItem Operation: enterItem(itemID: ItemID, quantity: integer) Cross References: Use Cases: Process Sale Preconditions: There is a sale underway. Postconditions: A SalesLineItem instance sli was created (instance creation). sli was associated with the current Sale (association formed). became quantity (attribute modification). sli was associated with a ProductDescription, based on itemID match (association formed). Hoa Sen University Contract definition A description of each section in a contract is shown in the following schema. Operation: Name of operation, and parameters Cross References: Use cases this operation can occur within Preconditions: Noteworthy assumptions about the state of the system or objects in the Domain Model before execution of the operation. These are non- trivial assumptions the reader should be told. .