《软件工程》期中试题解答.docx

1、软件工程期中试题解答软件工程期中试题一、选择题：1. The waterfall model of software development is also known as the ( ) A A. Classical life cycle model B. Fountain model C. Spiral model D. Chaos model2. The incremental model of software development is ( ) B A. A reasonable approach when requirements are well defined. B. A

2、good approach when a working core product is required quickly. C. The best approach to use for projects with large development teams. D. A revolutionary model that is not used for commercial products.3. COCOMO II is an example of a suite of modern empirical estimation models that require sizing info

3、rmation expressed as ( ) DA. function points B. lines of code C. application points D. any of the above4. An effective risk management plan will need to address which of the following issues ( ) DA. risk avoidance B. risk monitoring C. contingency planning D. all of the above5. The relationships sho

4、wn in a data model must be classified to show their ( ) C A. Width and depth B. Directionality and reliability C. cardinality and modality D. probability and risk6. The data dictionary contains descriptions of each software ( ) B A. configuration item B. data object C. diagram D. notation7. The stat

5、e transition diagram ( ) A A. indicates system reactions to external events B. depicts relationships between data objects C. depicts functions that transform the data flow D. indicates how data are transformed by the system 8. Which of the following is not an area of concern in the design model ( )

6、DA. architecture B. data C. interfaces D. project scope9. A program design language (PDL) is often a ( ) A A. combination of programming constructs and narrative text B. legitimate programming language in its own right C. machine readable software development language D. useful way to represent soft

7、ware architecture10. What types of errors are missed by black-box testing and can be uncovered by white-box testing ( ) BA. behavioral errors B. subtle logic errors C. performance errors D. input error11. To achieve high modularity of software components you need C A. high coupling and high cohesion

8、 B. high coupling and low cohesion C. low coupling and high cohesion D. low coupling and low cohesion12. Which of the following is not an objective for building an analysis model C A. define set of software requirements B. describe customer requirements C. develop an abbreviated solution for the pro

9、blem D. establish basis for software design13下图所示的软件模块结构图，该软件的宽度为（ ）。 DA1 B3 C5 D6 14面向对象的软件工程中，识别主类主要靠（ ）。 AA经验 B技巧 C启发式规则 D面向对象分析理论15用例图是（ ）。 DA系统特定行为的描述B系统行为之间交互的描述C系统和外部实体交互的描述D系统特定行为和外部实体以及和其他行为交互的描述二、简答题：1What are the differences between generic software product development and custom software

10、 development A：The essential difference is that in generic software product development, the specification is owned by the product developer. For custom product development, the specification is owned by the customer. Of course, there may be differences in development processes but this is not neces

11、sarily the case.2What are the four important attributes which all software products should have A：For important attributes are maintainability, dependability, efficiency and usability.3A software architecture describes a high-level design view of a software system. What are the advantages of explici

12、tly describing the architecture independently from the implementation参考答案（不够准确）：The architecture may have to be designed before specifications are written to provide a means of structuring the specification and developing different sub-system specifications concurrently, to allow manufacture of hard

13、ware by sub-contractors and to provide a model for system costing.4Explain why it is important to produce an overall description of a system architecture at an early stage in the system specification process. A：An overall architectural description should be produced to identify sub-systems making up

14、 the system. Once these have been identified, they may be specified in parallel with other systems and the interfaces between sub-systems defined.5Requirements should state what a system should do, without stating how it should do it. Why is this distinction useful6Define black box and white box tes

15、ting. What are the advantages of each approach Why are both necessary7Full path coverage testing requires that every possible path through the code be tested at least once. Why is full path coverage testing desirable For the code fragment above, how many test cases would be needed for full path cove

16、rage Why might full path coverage be impossible to achieve for some programs8Why is software maintenance difficult Why is it necessary9If you want develop an interactive system that allows railway passengers to find train times from terminals installed in stations, which generic software process mod

17、el that more suitable to management the development process And why A：Interactive timetable System with a complex user interface but which must be stable and reliable. Should be based on throw-away prototyping to find requirements then either incremental development or waterfall model.10Describe fou

18、r types of non-functional requirements that may be placed on a system. Give examples of each of these types of requirement.A：There are many possibilities here. Some suggestions are shown in Figure .Figure Non-functional requirementsNon-functionalrequirementDescriptionDescriptionPerformancePerformanc

19、e requirements setout limits to the performanceexpected of the system. Thesemay be expressed in differentways depending on the type ofsystem . number oftransactions processed persecond, response time to userrequests, etc.The system must process at least 150transactions per second.The maximum respons

20、e time for any userrequest should be 2 seconds.ImplementationDefines specific standards ormethods which must be used inthe development process for thesystemThe system design must be developed usingan object-oriented approach based on theUML process.The system must be implemented in C+,Version .Usabi

21、lityDefines requirements whichrelate to the usability of thesystem by end-users.All operations which are potentiallydestructive must include an undo facilitywhich allows users to reverse their action.(This is an example of a functionalrequirement which is associated with a nonfunctionalrequirement)A

22、ll operations which are potentiallydestructive must be highlighted in red in thesystem user interface.SafetySafety requirements areconcerned with the overall safeoperation of the systemThe system must be certified according toHealth and Safety Regulations XYZ 123.三、综合题1The following table shows the

23、estimated activity durations and pre-requisites for a project development. Activity Description Duration(weeks) Task Pre-requisites T1 Requirements Elicitation 4T2 Analysis & Design 3 1 T3 Install hardware 2 1 T4 Design Review 1 2 T5 Code & Unit Test 4 1,2,3,4 T6 Integration Test 2 5 T7 Porting Soft

24、ware 1 4,6 T8 Documentation 2 6,7 T9 Acceptance Test 3 5,6,7 T10 Install & Train 2 9 Draw a activity chart to determine the earliest week of completion, the activities which have some float or slack, and the activities on the critical path. Draw a bar chart showing the project schedule.2绘制打电话的状态转换图3

25、某校教务系统具备以下功能，输入用户ID号及口令后，经验证进入教务管理系统，可进行如下功能的处理：查询成绩：查询成绩以及从名次表中得到名次信息。学籍管理：根据学生总成绩排出名次信息。成绩处理：处理单科成绩并输入成绩表中。就以上系统功能画出0层，1层的DFD图。 教务系统0层DFD 图 教务系统1层DFD 图（身份验证处理框对应有一个用户信息的存储，名次表和学生成绩表应用存储的表示法）4一个自动化图书馆目录的软件系统要被开发。这个系统将要包含图书馆中所有图书的信息，要求该系统对图书管理员、借阅者和读者都可用。该系统应该支持目录浏览、查询，允许用户发送消息给图书管理员预订一本在借图书。识别出系统描述

26、中应考虑的基本视点，并用视点继承图（层次图）来描述它们之间的关系。 6版题A：The viewpoints are shown in Figure . Note that system management . thoseresponsible for installing and maintaining the computer system are a viewpoint aswell as library staff and library users. Library users have been separately identified asbrowsers and search

27、ers as these operations typically require different types of services.Figure Viewpoint hierarchy diagram5Develop an object model, including a class hierarchy diagram and an aggregation diagram showing the principal components of a personal computer system and its system software. A：There are many po

28、ssible organizations for the class hierarchy. I show a simple one in Figure with only two levels. A three-level hierarchy would also be OK but more than that would be too much. The aggregation diagram shows the part-of relationships between objects. This is shown in Figure . Obviously, further decom

29、position of the lowest level is possible.Figure Class hierarchy for a PCFig Aggregation diagram for a PC6Develop a sequence diagram showing the interactions involved when a student registers for a course in a university. Course may have limited enrolment, so the registration process must include che

30、cks that places are available. Assume that the student accesses an electronic course catalogue to find out about available courses. A：See Figure .Figure Sequence diagram of course registration7What is the fundamental difference between a fat-client and a thin-client approach to client-server systems

31、 development A：In a fat-client system, some of the application processing is carried out on the client whereas in a thin client system only the user interface is displayed on the client and all of the application processing is carried out on the server.8Using the UML graphical notation for object classes, design the following object classes identifying attributes and operations. Use your own experience to decide on the attributes and operations that should be associated with these objects: A printer for a