1 Rational Proprietary and Confidential Object Oriented Analysis and Design Using the UML Module 5: Identify Design Elements Module 5: Identify Design Elements 2 Rational Proprietary and Confidential Objectives: Identify Design Elements  Understand the purpose of the Identify Design Elements Understand the purpose of the Identify Design Elements and understand where in the lifecycle it is performed and understand where in the lifecycle it is performed  To understand how to analyze interactions of analysis To understand how to analyze interactions of analysis classes to identify design model elements classes to identify design model elements  Design classes  Subsystems  Subsystems Interfaces 3 Rational Proprietary and Confidential Identify Design Mechanisms in Context Architec t Identify Des ign Ele me nts 4 Rational Proprietary and Confidential Identify Design Elements Overview  The The Activity: Use Case Analysis Activity: Use Case Analysis results in results in analysis classes analysis classes , , which represent which represent conceptual things which can perform conceptual things which can perform behavior behavior . In design, . In design, analysis classes analysis classes evolve into a number evolve into a number of different kinds of design elements: of different kinds of design elements: 5 Rational Proprietary and Confidential Supplementary Specifications Software Architecture Document Design Model Design Model Design Guidelines Analysis Classes Identify Design Elements Overview Identify Design Elements 6 Rational Proprietary and Confidential Purpose  Purpos e Purpos e : :  To analyze interactions of analysis classes to find interfaces, classes and subsystems.  To refine the architecture, incorporating reuse where possible.  To identify common solutions to commonly encountered design problems.  To include architecturally significant parts of the design model in the Logical View 7 Rational Proprietary and Confidential Input and Output  Input Artifacts Input Artifacts : :  Supplementary Specifications  Glossary  Software Architecture Document  Design Model  Analysis Classes  Design Guidelines  Res ulting Artifacts Res ulting Artifacts : :  Design Model (Classes and Subsystems)  Updated Software Architecture Document  Updated Design Guidelines 8 Rational Proprietary and Confidential Class, Subsystem, interface overview  Classes, to represent a set of rather fine-grained Classes, to represent a set of rather fine-grained responsibilities; responsibilities;  Subsystems, to represent a set of coarse-grained Subsystems, to represent a set of coarse-grained responsibilities, eventually composed of a further set of responsibilities, eventually composed of a further set of classes and possibly subsystems; classes and possibly subsystems;  Interfaces, to represent abstract declarations of Interfaces, to represent abstract declarations of responsibilities provided by a class or subsystem; responsibilities provided by a class or subsystem; 9 Rational Proprietary and Confidential Identify Design Elements Steps  Identify classes and subsystems Identify classes and subsystems  Identify subsystem interacts Identify subsystem interacts  Update the organization of the design model Update the organization of the design model  Checkpoints Checkpoints 10 Rational Proprietary and Confidential Identify Design Elements Steps  Identify classes and subsystems Identify classes and subsystems  Identify subsystem interfaces Identify subsystem interfaces  Identify reuse opportunities Identify reuse opportunities  Update the organization of the design model Update the organization of the design model  Checkpoints Checkpoints [...]...From Analysis Classes to Design Elements Analysis Classes Design Elements Rational Proprietary and Many-to-Many Mapping 11 From Analysis Classes to Design Elements (cont.)  Analysis classes handle primarily functional requirements, and model objects from the "problem" domain; design elements handle nonfunctional requirements, and... the design (e.g components):  Communication software  Database access support  Types and data structures  Common utilities  Application-specific products Rational Proprietary and 32 Identifying Subsystems ClassA “Superman Class” Y() Z() InterfaceA SubsystemK Y() Z() Rational Proprietary and ? 33 Identify Design Elements Steps      Identify classes and subsystems Identify. .. components and don’t need to be “designed” at all Rational Proprietary and 12 From Analysis Classes to Design Elements (cont.)  Once the design classes and subsystems have been created, each must be given a name and a short description The responsibilities of the original analysis classes should be transferred to the newly-created subsystems Rational Proprietary and 13 Identify Design Classes  An analysis... and semantics Class Name  What is a package?  A general purpose mechanism for organizing elements into groups  A model element which can contain other model elements Package Name Rational Proprietary and 15 Group Design Classes In Packages  When identifying classes, they should be grouped into Artifact: Design Packages  You can base your packaging criteria on a number of different factors  Configuration... subsystems Identify subsystem interfaces Identify reuse opportunities Update the organization of the design model Checkpoint Rational Proprietary and 34 Identifying Interfaces  Once the subsystems are identified, their interfaces need to be identified  Purpose  To identify the interfaces of the subsystems based on their responsibilities  Steps       Identify a set of candidate interfaces for... contain other model elements, and a class, such that it has behavior  A subsystem realizes one or more interfaces, which define the behavior it can perform  A subsystem may be represented as a a UML package (e.g., a tabbed folder) with the «subsystem» stereotype Rational Proprietary and 25 Review: Subsystems and Interfaces  A “cross between” a package (can contain other model elements) and a class... used to:  Partition the system into units which can provide restricted security over key resources  Represent existing products or external systems in the design (e.g components) Subsystems raise the level of abstraction Rational Proprietary and 30 Identify Subsystems Hints       Look at object collaborations Look for optionality Look to the user interface of the system Look to the Actors Look... description The responsibilities of the original analysis classes should be transferred to the newly-created subsystems Rational Proprietary and 13 Identify Design Classes  An analysis class maps directly to a design class if:  It is a simple class  It represents a single logical abstraction  More complex analysis classes may  Split into multiple classes  Become a package  Become a subsystem (discussed . and Design Using the UML Module 5: Identify Design Elements Module 5: Identify Design Elements 2 Rational Proprietary and Confidential Objectives: Identify. Confidential Objectives: Identify Design Elements  Understand the purpose of the Identify Design Elements Understand the purpose of the Identify Design Elements and understand