Object-oriented analysis is a process of acquiring and understanding user's needs, analyzing the problem domain, confirming and establishing the conceptual model of problem area. and object-oriented design (OOD) is from the perspective of computer technology, the analysis of the concept of the phase of the model into a software system technology implementation, and in terms of function, performance and cost to meet the user and quality requirements of the process. is a process of transforming the object-oriented model in the problem space into a technology implementation model in the solution space.
Analysis is the process of extracting and collating user requirements and establishing an accurate model of the problem domain. Design is the process of transforming the requirements from the analysis phase into an abstract system implementation plan that meets the cost and quality requirements. Analysis and design is a multi-iteration process, many analysis results can be directly mapped to design results, and in the design process will often deepen and supplement the understanding of the system requirements, so as to further improve the analysis results.
Object-Oriented Analysis tasks
The design of the problem domain subsystem, the design of human-computer interaction subsystem, the design of task management subsystem and the design of data management subsystem
Problem Domain Subsystem Design
Object-oriented analysis obtains the exact model of the problem domain, which lays the foundation for designing the problem domain subsystem. Object-oriented design only complements the problem domain model from the implementation point of view and modifies the object-oriented method development software, ensures the stability of the problem domain organization framework, and facilitates the analysis, design and programming results. The problem domain subsystem is the solution of the definition problem, the expression class and the object static structure and the dynamic interaction relation in the software system, which is the core of the software system.
Main content:
1. Adjust and modify the model according to the latest changes in demand information
2. adjust and combine classes in the problem domain
3. Adjust the level of support inherited in the object model
4. Improve system performance
5. Add the bottom details
Design of human-computer interaction Subsystem
The human-Computer Interaction section highlights how people command the system and how the system submits information to the user. The friendliness of this part is directly related to the success or failure of the software system.
Design principles:
1. easy and friendly interface
2 a certain fault-tolerant or error-correcting mechanism
3. conform to user's usage habits.
interface elements to window as standard form.
command hierarchy, using the process abstraction mechanism, the system function is organized in order form.
1. Arrange the order
2. Overall-part relationship
3. Reasonable width and depth
4. Simple Operation procedure
Task Management Subsystem Design
A software system is a logical entity that accomplishes a system task. In a software system, some tasks are done sequentially, and some tasks must be done in a concurrent alternate way. Common tasks include event-driven tasks, clock-driven tasks, priority tasks, critical tasks, and coordination tasks. Design the task management subsystem, which includes identifying tasks and assigning tasks to the appropriate hardware or software to execute.
Data Management Subsystem
The function of data management subsystem is to provide the coordination and control function of data storage and access with the support of some kind of database management system .
The function and performance of data storage management impacting system 3 mode,
1. Document management system
2. relational database management system
3. Object- oriented database management system
Object-oriented design of "software Engineering"