软件工程导论 第5版考试知识点汇集.docx

1、软件工程导论 第5版考试知识点汇集软件工程导论(第5版)考试知识点汇集（Introduction to software engineering (Fifth Edition) exam knowledge collection）The first chapter is introduction to software engineering1.1 software crisis: a series of serious problems encountered in the process of software development and maintenance.In the foll

2、owing aspects:(1) the user is difficult to satisfied with the software.(2) the quality of software products are often unreliable.(3) general software difficult to maintain.(4) the software production efficiency is very low.(5) the cost of software development is more and more big.(6) the cost of sof

3、tware development and progress is difficult to estimate.(7) the development of the software technology can not meet the popularity of computer application and thorough need.Definition 2. software: software is another part of the computer system is interdependent with the hardware, it is including th

4、e procedures, collection of data and related documents complete. Software = program + data + document1.2. software engineering definition: to guide the development and maintenance of computer software engineering.The basic principle of software engineering, 4:1) with the phases of the life cycle pla

5、n strict management2) to review stage3) strict control products4) the adoption of modern design technology5) the results should be able to clearly review6) the development team should be few but good.7) acknowledge the need for continuous improvement of software engineering practice5. methods of Sof

6、tware Engineering ScienceUsually set a set of technical methods used in the whole process in the life cycle of software called methodology.Three elements: software engineering tools, methods and process.The traditional method; object oriented method.1.3 the software life cycleA, feasibility analysis

7、 and development plan: determine the development goals and the feasibility of the software.B demand analysis: on the development of software is feasible, the detailed analysis of the various functions of the software to achieve.C design (outline design and detailed design): mainly based on the resul

8、t of requirement analysis, design of the software system, such as system framework design, database design and so on.D, encoding: the software design results into computer running program code.E test: to go through rigorous testing in the software design is completed, to found in the whole design pr

9、ocess of software problems and correct.F maintenance: completed in software development and put into use, due to various reasons, the software can not continue to adapt to the requirements of the users.1.4 software process1.: the traditional waterfall model is a holistic development model, focus on

10、the late stage in the development process of the physical implementation, users see their products at the end of the can.2. rapid prototyping model: the user can give a complete and accurate description of the demand situation, according to the group of the basic needs of users, the rapid constructi

11、on of a prototype (software), and then evaluate the further refinement and adjustment of prototype, which meet the requirements of the users, developers will also make better do understand.3.: the incremental model is a gradual development and gradually improve the software version of the model.4. s

12、piral model: the spiral model is the organic combination of the waterfall model, prototype model and increment model, while increasing the risk analysisThe second chapter is the feasibility studyObjective: to determine whether the 2.1 feasibility study was proposed in the problem definition problems

13、 to solutions,In the limited conditions, can solve the problem.The feasibility study of the task:(1) further analysis and clarification of the definition of the problem, based on the clarification on the logic model of the system are derived;(2) from the system logic model, several kinds of main sol

14、ution selection problem, feasibility study of each kind of method, put forward suggestions for future action;(3) if the problem is not a viable solution, proposed to stop system development; if the problem has a feasible solution, we should recommend a better solution, and to develop a preliminary p

15、lan for the project.2.2 feasibility study content:(1): the technical feasibility of existing technology can realize the system, the existing technical staff can do, can meet the development of system resources;(2) economic feasibility: the economic benefits are beyond the cost of development;(3) ope

16、rational feasibility: in the operating system of internal user OK?(4) the legal feasibility: development of new systems would infringe collective or national interests, whether the violation of national laws.Feasibility study on the steps?(1) review system scope and objectives;(2) of the system curr

17、ently in use, summarize the existing system, put forward the new prototype system;(3) high level logic model to derive new system;(4) recommendation scheme;(5) the recommended course of action;(6) writing plan (feasibility report);(7) submitted for review.Figure 2.3 flow system: Graphical symbols fo

18、r each component of the system described by black box form2.5 data dictionary: a collection of all objects and the relationship between the information in the database.Methods: the data of top-down decomposition, when decomposed to not need further defined, and each project related people are aware

19、of its meaning element, then the decomposition process is over.2.6 cost benefit analysis cost estimation: the cost of software development mainly for human consumptionMethod of cost / benefit analysis: first estimates of costs and benefits; and then compare the costs and benefits, judging from the e

20、conomic point of view is developed. 1, the time value of money; 2, investment recovery period; 3, net income of 4, investment recovery rate.The third chapter: demand analysis3.1, requirements analysisTask: to accurately define the target system of the future, in order to determine what must be done

21、to meet the needs of users of the system.Demand: business requirements; user requirements; system requirements;3.2, to communicate with the user demand acquisition method: A, B, data flow oriented interviews; top-down refinementC, facilitated Application Specification Techniques; D, quickly set up a

22、 software prototype3.3, modeling and specification analysisConsists of:(1) Introduction: writing background and objective description, definitions and references.(2) the main function, constraints or special needs.(3) the data flow diagram and data dictionary.(4) user interface, hardware interface a

23、nd software interface.(5) performance requirements, properties etc.(6) other requirements, such as database, operation and troubleshooting etc.1) modeling and analysisModelIn order to understand things of things to make an abstract, is an unambiguous written description of thingsConsists of a set of

24、 symbols and rules of the organization of these symbols.Modeling methodThe data model and entity relationship diagram;? - function model of data flow graph; behavior model state transition diagram2) the software requirements specificationUsually use natural language + model, complete, accurate and s

25、pecific description of system data requirements, functional requirements, performance requirements, reliability and availability requirements, error handling requirements, interface requirements, constraints, and reverse demand which may be in the future.3.4, entity relationship diagram (E-R diagram

26、)The fifth chapter: the overall design5.1 design processThe system design stage: to determine the specific implementation of the system; structure design stage: to determine the structure of the softwareThe main task of the design is to complete the design of software structure, determine the relati

27、onship between module and module of the system.5.2 design principleThe 1. module: the program is divided into independent naming and independent access module, each module to complete a sub function of the modules are integrated together to form a whole, complete function and meet the requirements o

28、f users.Abstract: the 2. essential characteristics of abstract affairs while not to consider their details.3. step by step; 4. information hiding and localization of 5. independent modules;5.3 heuristic rules:1. improve the software structure to improve the module independenceThe 2. module size3. th

29、e proper control of the depth and width, fan out and fan inScope 4, module should be in control domain.5, reduce the complexity of interface6, a single entry single, avoid coupling7, the module function can be predictedThe sixth chapter: the detailed design6.1 program designThe classic definitionAre

30、 connected only through the sequence, selection and circulation of 3 kinds of basic control structure, and each code block has a single entrance, single export characteristicsComprehensive definitionAs far as possible the use of program design method of the GOTO statement. Use the GOTO statement is

31、best detected in error, and should always be used prior to the GOTO statementThe main task of detailed design?The software detailed design specification software to complete the work of the staff:(1) determined by the algorithm for each module, choose a suitable tool for expressing the algorithm pro

32、cess, write detailed process module description.(2) to determine the data structure of each module.(3) determine the module structure in detail, including the system external interface and user interface of the system, internal interface module and on the input data, output data and local data of all the details.(4) for each module design a set of test cases, so that in the encoding stage of the module code (i.e. program) scheduled for testing.Program control stru