"深入理解UML面向对象的分析与设计：子系统设计"

Subsystem design is a crucial step in the process of object-oriented analysis and design. It involves the creation of detailed specifications for the subsystems that will make up the final system. In the context of the development lifecycle, subsystem design is typically performed during the early elaboration iteration, when the overall architecture of the system is being defined. The main objectives of subsystem design are to describe the purpose of the subsystem, define the behaviors specified in its interfaces, document its internal structure, and determine its dependencies on external elements. This process helps ensure that each subsystem is clearly defined and can be implemented and tested independently, leading to a more modular and maintainable system overall. To achieve these objectives, developers can use UML (Unified Modeling Language) to create diagrams that represent the components and interactions within the subsystem. These diagrams can include class diagrams, sequence diagrams, and collaboration diagrams, among others. By using UML to visualize the subsystem design, developers can communicate their ideas more effectively and identify potential issues early in the development process. In conclusion, mastering subsystem design with UML is essential for developing complex software systems. By following the guidelines outlined in the DEV475_12_SubsystemDesign.pdf document and creating detailed specifications for each subsystem, developers can ensure that their systems are well-organized, easy to maintain, and meet the needs of their users.