西电软件工程概论复习笔记（含重点标注）

软件工程概论复习

有加粗的都是很重要的课后题中的对应题目。

文章目录

软件工程概论复习Chapter1 Introduction1.1 什么是软件工程？1、有关软件（重点）2、有关软件工程（重点）3、什么是好的软件工程（重点）4、谁做软件工程（重点）5、一个系统方法（1） what is a system？（2）The Elements of a System6、一个工程方法7、开发组的成员Chapter 2 Modeling the Process and Life Cycle1、The meaning of process(重点)（1）What is a process, a life cycle, and a software life cycle?（2）Understanding the concept of a process, prescription and description2、software process models（重点）（1）瀑布模型：（2）V模型：（3）螺旋式模型：（4）原型设计模型：（5）增量模型：简答题：Briefly describe the advantage and disadvantage of the WatterFall modelChapter 3 Planning and Managing the Project1、Tracking progress（1）What is a project schedule, an activity, and a milestoneproject scheduleactivitiesmilestone（2）Work breakdown and activity graphs工作分解和活动图表************************必考大题************************有关事件的关键路径与松弛时间有关活动的关键路径和松弛时间特别注意：最早开始时间和最晚开始时间都要+1处理！！！！！！！！2、Project personnel 项目人员（1）Staff roles and characteristicslines of communication（2）Work styles（3）Project organization3、 Effort estimation（1）Can not produce accurate estimates（2）Effort estimation techniques4、Risk management activities（1）What is a risk?（2）Steps in risk management（3）How to reduce risk?大题1、Give some diliverables：列出一些可交付物2、Briefly describe the characteristic of software development team's individual：描述软件开发团队个体的特征Chapter 4 Capture the Requirements1、What is a requirement?2、Requirements elicitation3、Types of requirement（重点）4、resolving conflicts——priority5、types of requirements documents需求说明书的类型6、Modeling notations建模符号（重点）（1）Entity-relationship diagrams（ERD）（重点）（2）Event traces（3）State machines（4）Data-flow diagrams (DFD)(重点)（5）Functions and relations7、Prototyping requirements大题1、Briefly describe the roles of the seven groups of stakeholders.简要描述七组利益相关者的角色2、 Briefly describe the function of the four types of the requirement.3、Briefly describe the functions of three core construct of ERD.4、Briefly describe the functions of the two approaches of prototyping.Chapter 5 Designing System1、What is a design？2、Decomposition and modularity分解和模块化3、Architectural styles and strategies架构风格和策略（1）Three design levels: architecture, code design, and executable design（2）Architectural styles• pipes and filers(重点)• Publish-subscribe（重点）Client/Server• Repositories 存储库架构• peer-to-peer• layering4、Issues in design creationChapter 6 Design the Modules1、Design Principles 设计原则软件架构的4+1视图模型（1） Modularity（2）What ?（重点）（3）Component independence （重点）【模块独立性】⚫耦合类型（重点）• Content coupling 内容耦合• Common coupling 公共耦合• Control coupling 控制耦合• Stamp coupling 特征/标记耦合• Data coupling 数据耦合⚫ 内聚类型（重点）• Coincidental cohesion• Logical cohesion• Temporal cohesion• Procedural cohesion• Communication cohesion• sequencial cohesion• Functional cohesioninformational cohesion大题Chapter 7 Writing the programs1、Programming Standards and Procedures2、Programming Guidelines3、Documentation （重点）大题Chapter 8 Testing the Program1、Software faults and failures（1）Types of faultsAlgorithmic faultComputation and precision fault 计算和精度错误Documentation faultCapacity or boundary faultsTiming or coordination faultsPerformance faultsStandard and procedure faults2、Testing issues（1）Test opinions（2）Test organization ——testing stepsModule testing,component testing, or unit testingIntegration testing 集成测试System testingfunction testperformance testacceptance testinstallation test（3） Testing techniques3、Unit testing （重点）（1）Examining the code （代码审查）（2）Success of the code reviews（3）Test thoroughness****************************************************************大题必考考点************************************************************************4、Integration testing（重点）（1）Bottom-up integration（2）Top-down integration（3） Big-bang integration（4）Sandwich integration（5）Comparison of the strategies大题Chapter 9 Testing the system1、Principles of system testing（重点）（1）Sources of software faults（2）System testing process（3）Configuration management（4） Test team2、Function Test3、Performance testing（1）Purpose and roles（2）Types of performance testing压力测试 stress test容量测试 Volumne test配置测试 configuration tes兼容性测试 compatibility test回归测试 regression test4、Reliability, availability, and maintainability （重点）（1）Definitionreliabilityavailabilitymaintainability（2）Measurement5、Acceptance testing（1）Purpose and roles（2）Types of acceptance tests6、Installation testing7、Test documentationChapter 11 Maintaining the System1、What is maintaining2、Four types of maintenance activities （重点）Corrective maintenance 改正性维护Adaptive maintenance 适应性维护Perfective maintenance 完善性维护Preventive maintenance 预防性维护大题

Chapter1 Introduction

1.1 什么是软件工程？

1、有关软件（重点）

软件 = 程序 + 数据 + 文档（去年考题）

Software is a set ofprogram(instruction),data(structure)anddocuments

解决问题：

方法工具过程范例

method tool procedure paradigm

2、有关软件工程（重点）

Software engineering means the application of asystematic,displinedandmeasureableapproach to thedevelopment,operationandmaintenanceof software. That is the application of engineering to software.

软件工程：使用系统的，有规律的，可测量的方法去开发，运行，维护软件。

Any Problem-solving technique must have two parts,analyzingto problem to determine its nature, and thensynthesizinga solution

分析问题综合解决方法

3、什么是好的软件工程（重点）

TheMcCall’s quality modelconcerns the quality ofthe software product,

CMMconcerns the quality ofthe process of development software product

andROIconcerns the quality of the context ofthe bussiness environment

4、谁做软件工程（重点）

customer + developer + user

Thecustomeris the company, organization ,or a person who is paying for the software system to be developed.Thedeveloperthe company, organization ,or a person who is building the software system.Theuseris the person or people who will actually use the system.

5、一个系统方法

（1） what is a system？

system is a collection ofobjectsandactivities, plusa description of the relationshipsthat tie the objects and activities together.

系统是对象和活动的集合，加上对象和活动之间关系的描述。

（2）The Elements of a System

objects and activitiesrelationship and the system boundaryexamples of system

6、一个工程方法

Building a system

软件开发的活动：（在大纲中，但不一定是重点，课后题无这个题目）

需求分析和定义 ——Requirement analysis and definition交流设计 ——System design程序设计 ——Program design写程序（程序实现） ——Writing the programs单元测试 ——Unit testing & 整体测试 ——Integration testing系统交付 ——System testing维护——Maintenance

The software development usually involvesrequirementanalysing and defination,system design, program design, program implementation, unit testing, integration tesing, system deliveryandmaintenancestages

7、开发组的成员

analystdesignerprogrammertestertrainer

Any entity to be engineered ,we must doanalyst,designer,construction,verificationandmanagment

简答：Briefly describe the roles of analyst, designer, programmer, tester, and trainer.

the requirementanalystwork with customer, break down what the customer wants into discrete requirement.

与客户一起工作，将客户的需求分解成离散的需求。

the designer generate the system-level description of what the system is to do

生成关于系统要做什么的系统级描述

the programmer write line of code that implement what requirement specify.

编写一行行代码，实现需求指定。

the tester catches faults that programmer overlook

发现程序员忽略的错误

the trainer shows users how to use the system

培训师向用户展示如何使用该系统

Chapter 2 Modeling the Process and Life Cycle

1、The meaning of process(重点)

（1）What is a process, a life cycle, and a software life cycle?

process

We can think a set of ordered tasks as aprocess, a series ofsteps, includingactivities,constrainsandresources

过程：一系列的顺序任务，过程 = 步骤 —— 活动 + 约束 + 资源

lifecycle

When the process involves building of someproduct, we sometime refer to the Process as alifecycle

当过程涉及到构建某些产品时，我们有时将过程称为生命周期。

software lifecycle

The life cycle of a software product includeconception , implementation, delivery, use,andmaintenance

软件的生命周期：概念---->实现---->交付—>使用---->维护

（2）Understanding the concept of a process, prescription and description

2、software process models（重点）

Several typical software process models – description, advantages and disadvantages and examples

Waterfall modelV modelPrototyping modelPhased development: increments and iterationsSpiral modelAgile methods

（1）瀑布模型：

Thewaterfall modeincluderequirement analysis, system design, program design, coding, unit & integration testing, system testing, acceptance testing,andoperation & maintenance steps.

增加了两个V的瀑布模型：

Thevalidationensures that the system has implemented all of the requirement, But theverificationensures that each function works correctly. 有效性 + 认证

优点：

模型简单，客户和开发人员容易理解

为项目提供了按照阶段划分的检查点

精确定义了每位开发人员的不同职能

可强迫开发人员采用规范化的方法

说明了每个主要阶段完成的里程碑或可交付产品

缺点：

由于瀑布模型几乎完全依赖于书面的规格说明，很可能导致最终开发出的软件产品不能真正满足用户的需要

只适用于项目开始时需求就已经确定的情况，无法应对开发过程中需求的变更

将软件开发视为一个制造过程而不是一个创造过程

往往需要很长时间才能得到最终产品

适用情况：

开发已经有明确规定的确定项目

需求一旦确定便不再发生变化

组织具有明确分工的项目

重新开发一个与之前相同的项目，即重复开发

（2）V模型：

TheV modelmakes more explicit some of theiterationandreworkthat are hidden In the waterfall model

优点/特点：

测试与需求相对：

采用参与测试来验证程序设计采用集成测试来验证体系结构采用验收测试来确认需求。

验证过程中发现问题即可在执行后续测试步骤前重新执行左边步骤对软件修正。

（3）螺旋式模型：

The spiral model combine the development activities withriskmanagement to minimize and control therisk control。

瀑布模型与原型模型的组合，既可以周期性地验证客户的需求，又可以分阶段进行开发工作，能保证软件在遇到较大风险时停止，大大增强了软件的风险防控能力。但是过程很复杂，需要开发人员有丰富的风险评估能力和专业知识，适合大型项目的开发。

优点：

将开发活动与风险管理相结合以最小化控制风险

较好地满足用户的需求

缺点：

开发成本高，对开发人员要求高

（4）原型设计模型：

在需求分析阶段对软件进行初步的分析和定义，快速开发出简单的软件原型并向用户展示，用户对软件原型进行测评后进一步提出进要求，开发人员的原型修改到用户满意为止。因此原型模型的开发更能符合需求，适合市场导向（market-driven）的产品。

Aprototyping modelis a partially developed product that enable customers and developers。 To examine some aspect of the proposed system and decide if it is suitable or appropriate for the final product.

优点：

很好地满足客户的真实需求

原型系统已经通过与用户进行交互而得到验证，据此产生的规格文档能正确描述用户的需求

软件产品的开发基本是线行进行

建造出原型系统后，开发人员可以加速软件开发过程，节约软件开发成本

（5）增量模型：

增量：将系统功能划分为诸多子系统，先开发具有一个小功能的子系统，之后不断在子系统上增加新的功能来逐渐满足所有需求

迭代：第一次提交的产品就是一个完整的系统，之后在该系统的基础上不断修改，不断开发出新的版本，但是每个版本都是完整可运行的版本。

优点：

逐步增加产品功能使用户有充足的时间学习和适应新产品

一部分一部分的开发，能在较短时间内就向用户提供一个有用功能的产品

项目的风险较低，能较好满足客户需求

简答题：Briefly describe the advantage and disadvantage of the WatterFall model

优点：

模型简单，用户和开发者容易理解为每一位开发者精细划分了不同职能说明了每一个重大阶段完成的里程碑或可交付产品强迫开发者开发使用规范的方法

缺点：

严格按照书面的规格说明，最后的产品可能和用户的要求不符合把开发视作一个制造过程而不是一个创造过程可能需要很长时间才能得到产品

Chapter 3 Planning and Managing the Project

1、Tracking progress

（1）What is a project schedule, an activity, and a milestone

project schedule

Aproject scheduledescribes the software development cycle for a particular project by enumerating thephasesor stages of the project and breaking each into discretetasksoractivitiesto be done.

项目进度表通过列举项目的阶段，并将每个阶段分解成独立的待完成的任务或活动，来描述一个特定项目的软件开发周期。

The Schedule is atimelinethat shows when activities will begin and end, and When the related development products will be ready.

The Deliverables , that is theitemthat the customer expects to see during project development.

交付物，即客户希望在项目开发期间看到的项目。

activities

Anactivityis a part of the project thattakes place over a period of time, whereas amilestoneis the completion of an activity- a particular point of time

milestone

amilestoneis the completion of an activity- a particular point of time

（2）Work breakdown and activity graphs工作分解和活动图表

TheGantt Graphdepicts the project as a set of discrete pieces of work.

甘特图将项目描述为一组离散的工作片段。

Thereal timeoractual timefor an activity is the estimated amount of time required for the activity to be completed. Theavaliable timeis the amount of time available in the schedule for the activity’s completion.slack timeorfloat timefor an activity is the difference between theavaliable timeandreal timefor that activity

Thecritical pathis a path that the slack time at every node is zero.

GANTT CHART is used to depict the projects’CMP.

必考大题

Estimating completion

CPM (Critical Path Method)

slack time for an activities

求关键路径：

求关键路径只需要找到最早开始时间和最迟发生时间相等的事件即可。

有关事件的关键路径与松弛时间

最早开始时间：【从前往后算】，事件vi的最早开始时间 = 从源点v1到顶点vi的最长路径长度最迟发生时间：【从后向前算】，事件vi的最迟发生时间 =earliest(n)- （从定点vi到vn的最长路径）

另外还有一个概念为松弛时间slack time ，为最早开始时间和最迟开始时间二者的差，也就是说关键路径的节点就是松弛时间为0的点。

slacktime(i)=lasteststarttime(i)−earlieststarttime(i)slack\quad time(i) = lastest\quad start\quad time(i) - earliest\quad start\quad time(i) slacktime(i)=lasteststarttime(i)−earlieststarttime(i)

例题1：

松弛时间计算如上表，关键路径为：

START−>2−>5−>7−>8−>FinshSTART -> 2->5->7->8->Finsh START−>2−>5−>7−>8−>Finsh

例题2：

松弛时间计算如上表，关键路径为：

START−>D−>F−>H−>FinshSTART -> D->F->H->Finsh START−>D−>F−>H−>Finsh

有关活动的关键路径和松弛时间

对于活动：ak=<vi,vj>a_k = <v_i, v_j>ak=<vi,vj>

活动aka_kak的最早开始时间 = 事件viv_ivi的最早开始时间

活动aka_kak的最晚发生时间 = 事件 vjv_jvj的最迟发生时间 - 完成该活动的计划时间。

特别注意：最早开始时间和最晚开始时间都要+1处理！！！！！！！！

例3：

例：

所以，关键路径为：

1−>2−>5−>7−>81 -> 2->5->7->8 1−>2−>5−>7−>8

2、Project personnel 项目人员

（1）Staff roles and characteristics

lines of communication

如果一个工作中有n个人，那么一共有n（n-1）/ 2条交流线

characteristics

Extrovert（外向）: tell their thoughts

Introvert（内向）: ask for suggestions

Intuitive（直觉）: base decisions on feelings

Rational（理智）: base decisions on facts, options

（2）Work styles

（3）Project organization

组织形式取决于下面三个因素：

小组成员的背景和工作风格 backgrounds and work styles of team members 内向/外向理智/直觉小组成员数 number of people on team客户和开发者的管理风格 management styles of customers and developers

组织形式：

chief programmer team：高效的组织方式

Each team member must communicate often with chief, but not necessarily with other team members

试用：

重复性高确定性大项目

egoless approach

适用：

不确定性新技术小项目

3、 Effort estimation

（1）Can not produce accurate estimates

（2）Effort estimation techniques

expert judgmentalgorithmic methodsmachine-learning methods

4、Risk management activities

（1）What is a risk?

Risk management is concerned withidentifying risksanddrawing up plansto minimize their effect on a project。

（2）Steps in risk management

风险管理：{风险评估{风险识别风险分析风险分级风险控制{减少风险风险管理计划风险解决风险管理：\begin{cases} 风险评估\begin{cases} 风险识别\\ 风险分析\\ 风险分级 \end{cases} \\风险控制 \begin{cases} 减少风险\\ 风险管理计划\\ 风险解决 \end{cases} \end{cases} 风险管理：⎩⎪⎪⎪⎪⎪⎪⎪⎪⎨⎪⎪⎪⎪⎪⎪⎪⎪⎧风险评估⎩⎪⎨⎪⎧风险识别风险分析风险分级风险控制⎩⎪⎨⎪⎧减少风险风险管理计划风险解决

（3）How to reduce risk?

大题

1、Give some diliverables：列出一些可交付物

documentsdemonstrations offunctiondemonstrations ofaccuracydemonstrations ofsubsystemsdemonstrations ofreliability, performance or security

2、Briefly describe the characteristic of software development team’s individual：描述软件开发团队个体的特征

ability to perform the work 能力interest in the work 兴趣experience with similar **applications **experience with similartools or langugesexperience with similartechniquesexperience with similardevelopment environmenttrainning训练ability to communicate with others

Chapter 4 Capture the Requirements

1、What is a requirement?

A requirement is anexpressionofdesired behavior。

Requirements focus on the customer needs, not on the solution or implementation

2、Requirements elicitation

The process for capturing the requirement has four steps, there areelicitation，analysis,specification,andvalidation。

需求抽取 requirement elictation

需求分析 analysis

需求规范 Requirements Specification

需求规范

将需求整理为规范性的文档。what the designers need to know

用户、设计者、测试人员是需求文档的直接使用者，而程序员不是。

需求验证

3、Types of requirement（重点）

There four type of requirement, they are thefundmental requirement , Quality requirements/nonfunctional requirements,design contraistandprocess constraist.

功能性需求

input or required activities

举例：

System shall communicate with external system X.

What conditions must be met for a message to be sent.

非功能性需求/质量需求

Paychecks distributed no more than 4 hours after initial date are read.System limits access to senior managers.

设计限制

接口与组件限制设计

过程限制

技术和资源限制

4、resolving conflicts——priority

correct ：we and customer read it , and they comfirm our understandingconsistant：no conflicting requirementunambigious：muliple readers of the requirements can walk away with different but valid interuptionscomplete：specifies required behavior and output for all possible inputs in all possible states under all possible constraints.feasible： there is a solutionrelevent：restricts the developers unnecessarily, or includes functions that are not directly related to the customer’s needs.testable：acceptance tests that would clearly demonstrate whether the eventual product meets the requirements.traceable：the requirements organized and uniquely labeled for easy reference.

5、types of requirements documents需求说明书的类型

Requirements definition

a complete listing of everything the customer wants to achieve一份关于软件功能的完整清单，是给用户看到，用户希望实现的功能。what the customer wants

Requirements specification

restates the requirements as a specification of how the proposed system shall behave

将需求整理为规范性的文档。what the designers need to know

用户、设计者、测试人员是需求文档的直接使用者，而程序员不是。

6、Modeling notations建模符号（重点）

（1）Entity-relationship diagrams（ERD）（重点）

Definition

a popular graphical notational paradigm for representing conceptual models

表示概念模型的流行图形符号

表示概念模型的一种方法，包含实体，联系，属性三个要素。对应UML中的类图。

Three elements

Entity实体—矩形relationship联系— 菱形attribute属性—标注

Properties/application

ER图之所以流行是因为：

提供了解决问题的概述当修改问题的要求时，视图相对稳定

ER表示法的简单性具有欺骗性。实际上，在实践中很好使用ER建模是非常困难的

建模标准：

选择是否会导致更清晰的描述一个选择是否不必要地限制了涉及决策

UML class diagrams

与ER图相似

（2）Event traces

Definition

对现实世界实体之间交换的一系列事件的图形描述。

Properties/application

垂直线：不同实体的时间轴，其名称出现在线的底部

水平线：分界线上的两个实体的交互作用

UML sequence diagrams

（3）State machines

Definition

系统与环境之间所有对话的图形化描述

Two elements

node：状态，表示事件之间的稳定关系edge：表示事件的发生而导致的行为或条件

Properties/application

UML statechart diagrams

（4）Data-flow diagrams (DFD)(重点)

Definition

ER图，Events trace ，state machine只是描述比较低级的行为

数据流图DFD对从一个功能到另一个功能的数据进行描述

Four elements

Process气泡表示过程data flow箭头表示数据流data store信息的正式存储或者数据库actors矩形代表参与者

Properties/application

优点：

Provides an intuitive model of a proposed system’s high-level functionality and of the data dependencies among various processes

缺点：

对不熟悉建模的人来说可能有点模糊

UML use case diagrams

DFD与用例图相似

（5）Functions and relations

Decision table

7、Prototyping requirements

Rapid prototypingThrowaway prototypingEvolutionary prototyping

Prototyping vs. modeling

There are two approaches to prototype, they are thethrowaway prototypeandevolution prototype.

In UCD, a large box represents the systemboundary.

大题

1、Briefly describe the roles of the seven groups of stakeholders.简要描述七组利益相关者的角色

client：who are the ones paying for the software to be developedCustomers: buy the software after it is developedUsers: use the systemDomain experts: familiar with the problem that the software must automateMarket Researchers: conduct surveys to determine future trends and potential customersLawyers or auditors: familiar with government, safety, or legal requirementsSoftware engineers or other technology experts

2、 Briefly describe the function of the four types of the requirement.

functional requirement：describes required behavior in terms of required activities

根据需要的活动描述需要的行为

qualtity requirement：describes some quality characteristic that the software solution must possess

描述软件解决方案必须具备的一些质量特征

process constraint：a restriction on the techniques or resources that can be used to build the system

对可用于构建系统的技术或资源的限制

design constraint：a design decision, such as choice of platform or interface components, that has already been made and that restricts the set of solutions to our problem

一个已经做出的设计决策，例如平台或接口组件的选择，它限制了我们的问题的解决方案集

3、Briefly describe the functions of three core construct of ERD.

entity：represents a collection (sometimes called a class) of real-world objects that have common properties and behaviors.

表示具有公共属性和行为的现实世界对象的集合(有时称为类)。

relationship：an edge between two entities, with a diamond in the middle of the edge specifying the type of relationship

两个实体之间的边缘，边缘中间的菱形指定关系类型。

atrribute：an annotation on an entity that describes data or properties associated with the entity.

实体上的一种注释，用于描述与该实体相关联的数据或属性。

4、Briefly describe the functions of the two approaches of prototyping.

throwaway prototyping：A throwaway prototype is software that is developed to learn more about a problem or about a proposed solution, and that is never intended to be part of the delivered software.

一次性原型是为了更多地了解问题或建议的解决方案而开发的软件，它绝不是交付软件的一部分。

evolution prototyping：an evolutionary prototype is software that is developed not only to help us answer questions but also to be incorporated into the final product.

进化原型是一种软件，开发它不仅是为了帮助我们回答问题，而且是为了整合到最终产品中。

Chapter 5 Designing System

1、What is a design？

Design is thecreative processof figuring out how to implement all the customer’s requirements; theresultingplan is called the design.

Two stage of design

● Conceptual design or System design 概念设计/系统设计

● Technical design 技术设计

好的设计具备的特点：

构建独立性异常标识和处理放错和容错技术

2、Decomposition and modularity分解和模块化

High level – lower level

Modular decomposition 模块化分解函数分配给模块 assign functions to modules

Data-oriented decomposition 面向数据分解 based onexternal data structure

Event-oriented decomposition 面向事件 based oneventsystem must handle

Outside-in design 从内到外设计 based on userinput

Object-oriented design 面向对象设计 identifying classes of objects and internal relationship

Starting with a high-level depiction of the system’s key elements and creating lower-level looks at how the system’s features and functions will fit together

从对系统关键元素的高级描述开始，然后创建较低级别的视图，了解系统的特性和功能将如何组合在一起

3、Architectural styles and strategies架构风格和策略

（1）Three design levels: architecture, code design, and executable design

体系结构，代码设计和可执行设计

The software architecture is consisted by three parts, they arecomponents,connectorsandconstraits.

架构体系：

组件连接器限制

（2）Architectural styles

• pipes and filers(重点)

每个模块都有一组输入与输出，每个模块从输入端接收数据流，内部处理后按照标准顺序将数据送至输出端，这种模式成为过滤器，而各个过滤器之间连接的导管，起数据传递的作用，称为管道。

过滤器就是对数据进行处理的模块，而管道就是传递数据的通道，注意管道是支持并行的（concurrent execution），此模式可以描述并行的系统。

In pipe-and-filter style, thefilterfunctions is to pass input data through a sequence of data-transforming components, and thepipesimply transmit data from one filter to the next without modifying the data.

过滤器函数是通过一系列数据转换组件传递输入数据，而管道只是将数据从一个过滤器传输到下一个过滤器，而不修改数据。

优点：

设计者可以理解整个系统对输入和输出的影响，作为过滤器的组成

The designer can understand the entire system’s effect on input and output as the composition of the filters

过滤器可以很容易地在其他系统上重复使用

the filters can be reused easily on other system

系统进化很简单

system evolution is simple

允许并发执行过滤器

allow concurrent execution of filters

缺点

鼓励批处理

encourage batch processing

不适合交互式应用

not good for handling interactive application

过滤功能重复

duplication in filters function

• Publish-subscribe（重点）

In publish-subscribe architecture, Asubstribecomponent express interest in an event by to it. When another component that the event has take place, the subscribing component are notified。

在发布-订阅体系结构中，订阅组件通过它表达对事件的兴趣。当另一个组件发生该事件时，订阅组件将得到通知。

隐式调用(implicit invocation) is a common form of publish-substribe architecture

优点

对进化和定制的强大支持

Strong support for evolution and customeization

易于在其他事件驱动系统中重用组件组件

easy to reuse components in other event-driven systems

缺点

需要共享存储库来共享持久数据

need shared repository for components to share persistent data

难以测试

difficult to test

Client/Server

• Two types of components:

– Server components offer services

– Clients access them using a request/reply protocol

In client-server architecture, theservercomponent offer services, andclientaccess them using a request/reply protocol.

在客户机-服务器架构中，服务器组件提供服务，而客户机使用请求/应答协议访问它们。

• Repositories 存储库架构

A repository style consists oftwo types of component,one is calledcentral data store, another is calleddata accessingcomponent.

Major advantage: openness

– Data representation is made available to various programmers (vendors) so they can build tools to access the repository

– But also a disadvantage: the data format must be acceptable to all components

• peer-to-peer

In peer-to-peer architecture, eachpeerexecutes as its own process and acts as both a client and a server to other peer component.

在对等体系结构中，每个对等点作为它自己的进程执行，并且作为其他对等组件的客户端和服务器。

Any component can initiate a request to any other peer component.

• layering

Layers are hierarchical

High levels of abstraction

Relatively easy to add and modify a layer

4、Issues in design creation

➢ Modularity and levels of abstraction

➢ Collaborative design

➢ Concurrency

Chapter 6 Design the Modules

1、Design Principles 设计原则

This chapter can help you see why certain designprinciplesandconventionsare applicable, and then assist you in deciding when should apply them.

In practice, there is nosharp bundarybetween the end of the architectural design phase and the start of the module design phase.

在实践中，在架构设计阶段的结束和模块设计阶段的开始之间没有明显的边界。

Design principles are guidelines fordecomposingour system’s required functionality and behavior into modules.

设计原则是将系统所需的功能和行为分解为模块的指导方针。

软件架构的4+1视图模型

逻辑视图

将系统中的关键抽象为对象或者对象类

进程视图

显示系统在运行时是如何由相互作用的进程组成的

开发视图

显示如何对软件进行分解

物理视图

显示系统硬件和软件组件如何分布在系统的处理器

（1） Modularity

Design modules means decide how theindividual componentwill be designed at a modular level so that developers canwrite codethatimplementthe design.

Modularity, also calledseparation of concern, is the principle of keeping separating The various unrelated aspects of the system.

模块化，又称为分离关注

本章可以帮助你了解为什么某些设计原则和约定是适用的，然后帮助你决定什么时候应该应用它们。

（2）What ?（重点）

ModularityInterfacesInformation hidingIncremental development 增量开发AbstractionGenerality 普遍性

（3）Component independence （重点）【模块独立性】

Why component independence?

⚫耦合类型（重点）

• Content coupling 内容耦合

一个模块直接使用或者修改另一个模块内部的数据，或者通过非正常的入口，直接进入另一个模块的内部。比如在某个组件的分支操作，直接进入到了另一个组件之中（one component branches into the middle of another component）。

• Common coupling 公共耦合

几个模块对一个公共的数据区域进行数据上的操作

• Control coupling 控制耦合

一个模块通过传递参数，或者函数的返回值来控制另一个模块的行为

• Stamp coupling 特征/标记耦合

complex data structures are passed between modules

When complex data structures are passed between modules, we say that There isstamp couplingbetween the modules,

• Data coupling 数据耦合

几个模块共享几个数据的值

if only data value, and not structured data, are passed, then the modules are connected bydata coupling.

⚫ 内聚类型（重点）

cohesion：内部元素之间的依赖关系

• Coincidental cohesion

coincidental, is found in a module whose parts are unrelated to one another. In this case, unrelated functions, processes, or data are combined in the same module for reasons of convenience or serendipity.

模块之间毫无关系，相互之间是松散的

• Logical cohesion

logical cohesion if its parts are related only by thelogic structureof its code.

举例：if - else

• Temporal cohesion

一个模块完成的许多功能必须在相近的时间点完成，比如系统的初始化，这些功能通过时间因素关联在一起。

in that a module’s data and functions are related only because theyare used at the same time in an execution.

• Procedural cohesion

允许在调用前面的构件或操作之后，马上调用后面的构件或操作，即使两者之间没有数据进行传递

When functions are grouped together in a module to encapsulate the order of their execution, we say that the module is procedurally cohesive.

• Communication cohesion

一个模块的所有成分都操作同一数据集或者生成同一数据集

同一个data set

• sequencial cohesion

指一个模块中各个处理元素都密切相关于同一功能且必须顺序执行,前一功能元素的输出就是下一功能元素的输入

• Functional cohesion

where two conditions hold: all elements essential to a single function are contained in one module, and all of that module’s elements are essential to the performance of that function.

这里有两个条件:一个模块中包含对单个函数至关重要的所有元素，而该模块的所有元素对该函数的性能都至关重要。

informational cohesion

功能内聚对数据抽象和基于对象的设计的适应性称为信息内聚。

The adaptation of functional cohesion to data abstraction and object-based design is called informational cohesion.

大题

1、Do the exercise 7 of this chapter ( Fourth Edition P370) For each type of coupling, give an example of two components coupled in that way.

content coupling

一个模块直接使用或者修改另一个模块内部的数据：组件1读取字符流并且更新组件2内部的数据，该变量跟踪已经读取的行数

组件2使用此变量计算需要启动新页面的时间。

或者通过非正常的入口，直接进入另一个模块的内部。比如在某个组件的分支操作，直接进入到了另一个组件之中

common coupling

几个模块对一个公共的数据区域进行数据上的操作

组件1和2与上面一样，但是行计数器变量位于共享数据空间中。

control coupling

组件1读取字符流，跟踪读取的行数，每当读取足够的行开始一个新页时，就调用组件2。

stamp coupling

complex data structures are passed between modules

组件1对一个复杂的数据结构执行有效性检查，然后将该结构传递给组件2，组件2根据该结构中的数据执行计算。

data coupling

几个模块共享几个数据的值

组件1对复杂的数据结构执行有效性检查，然后传递组件2完成计算所需的数据结构的各个元素

Chapter 7 Writing the programs

1、Programming Standards and Procedures

Standard format for comments

Even when writing the code itself, many people are sually involved, and a great deal ofcoorperationandcoordinationis required.

2、Programming Guidelines

May companies insist that their code conform tostyle ,format , content standardandreadstandards, so that the code and associatedstandardare clear to everyone whoreadthem.

程序的主要层次

控制结构

控制结构主要指程序的分支结构，展现程序的控制流结构。控制单元可以让代码更易阅读，同时将诸多独立的模块组织成有逻辑联系的程序，还可以在控制结构中加入传递参数的名字或者一定的注释，从而展现各组件之间的耦合性。

算法

算法有着共同的目标：性能（速度）。同时更高效的算法也能让编写、理解、测试、修改代码的成本降低

数据结构

使用数据结构来将程序中的数据组织起来，从而让程序尽可能保持简单。

No matter how what language is used, each program component involves At least three major aspects,control structure,algorithm, anddata structure.

3、Documentation （重点）

➢ Internal documentation

内部文档经常以注释的方式包含在程序之中，是可以直接写在程序里面的，写法一般有固定的格式。

internal documentationis descriptive material written within the code,

内部文档包含内容：\begin{cases}

标题注释块 Head block comment\begin{cases}

组件的名称\

组件的编写者\

组件在一般系统设计中的位置\

编写和修订组件的时间\

组件的功能和作用\

组件是如何使用其数据结构、算法和控制流程的\

\end{cases}\

有意义的变量名和语句标签\

其他程序注释\

\end{cases}

➢ External documentation

The programdocumentationto be the set of written descriptions that explain to a reader what the programs to and how they do it.internal documentationis descriptive material written within the code, all other documentation isexternal documentation.

The external documentation is the full blown report, it answers the same questionswho, what , why , when , where , how ,and using a system rather than a component perspective。

大题

1、Briefly describe the content of Head Block Comment.

what your component is calledwho wrote the componentwhere is the conponent fits in general system designwhen the conponent is written or revisedwhy the conponet exsitshow the conponent uses its data structures, algorithms, and control structure

Chapter 8 Testing the Program

1、Software faults and failures

（1）Types of faults

A fault occurs when a human makesmistakes, called an error, in performing some software behavior. Thus a fault is aninsideview of system, as seen by the eyes of thedeveloper.

Afailureis adeparturefor the system’s required behavior. Thus a failure is anoutsideview: a problem that theusersees.

Algorithmic fault

An algorithm fault occurs when a component’salgorithmorlogicdoes not produce the proper output for a given input.

语法错误也属于算法错误

Computation and precision fault 计算和精度错误

a formula’s implementation is wrong

Computation and precision faults occur when a formula’simplementationWrong or dose not compute the result to the required number ofdecimalplaces.

当一个公式的实现是错误的或没有计算到小数点后所需的位数。

Documentation fault

Documentation doesn’t match what program does

When the documentation does not match what the program actually Dose, we say that the program hasdocumentation.

Capacity or boundary faults

System’s performance not acceptable when certain limits are reached。

Stress or overload fault occur when the data structures are filled past their Specifiedcapacity.

当数据达到一定大小超出容量限制时，系统无法接受而报错。

Timing or coordination faults

Performance faults

System does not perform at the speed prescribed

Standard and procedure faults

并不是所有错误都能够复现的。

Fault identification is the process ofdeterminingwhat the fault or faults Caused the failure, and fault correction or removal is the process ofmaking changingto the system so that the faults are removed.

2、Testing issues

（1）Test opinions

（2）Test organization ——testing steps

Module testing,component testing, or unit testing

each program component is tested on its own, isolated from the other components in the system.

Integration testing 集成测试

将所有组件组装成一个整体进行测试

Integration testing is the process of verifying that the system components work together as described in the system and program design specifications.

集成测试是验证系统组件按照系统和程序设计规范中所描述的协同工作的过程。

Ainstallationtest is run to make sure that the system still functions as it should.

System testing

包括：function test, performance test, acceptance test, and installation test

function test

Afunctiontest evaluates the system to determine if the functions described by the requirements specification are actually performed by the integrated system.

按照系统的功能需求进行测试

performance test

Aperformancetest compares the system with the remainder of these software and hardware requirements.

测试除功能外其他的项目，如速度、精度等

acceptance test

Aacceptancetest checks against the customer’s requirement description, and This test complete jointly with the customer.

让顾客针对具体软件确认自己的需求

installation test

在用户的计算机环境下进行安装测试

（3） Testing techniques

Black box

定义：已知产品应该具有的功能，通过测试检验其每个功能是否都能够正常使用。又称功能测试

用途：把程序看成一个黑盒子，仅仅考虑输入和输出的对应关系和程序接口，完全不考虑它的内部结构和处理过程。一般用于综合测试、系统测试等

We view the test object form the outside as a closed or black box whose contents are unknown, our testfeedinputs to the closed box and notes whatoutputis produced.

White box

已知产品内部的工作过程，通过测试检验产品内部动作是否都能按照需求定义的规定正常使用。用途必须完全了解程序的内部结构和处理过程，才能按照程序内部的逻辑测试，以检验程序中每条路径是否正确，因此一般用于规模较小的程序和单元测试

We view the test object as an open box and or white box, we can see thestructureof the test object to test in different way.

测试技术{黑盒测试：只考虑输入和输出对应关系和程序接口，不考虑内容{划分等价类equivalenceclasspartitioning边界测试boundarytest白盒测试{语句覆盖statementcoverage：每个语句至少执行一次条件覆盖conditioncoverage：每个判断的真假至少执行一次边界覆盖boundarycoverage：每个组件的边界条件进行测试穷举测试测试技术\begin{cases} 黑盒测试：只考虑输入和输出对应关系和程序接口，不考虑内容 \begin{cases} 划分等价类\quad equivalence class partitioning\\ 边界测试\quad boundary test\\ \end{cases}\\ 白盒测试\begin{cases} 语句覆盖\quad statement\quad coverage：每个语句至少执行一次\\ 条件覆盖\quad condition\quad coverage：每个判断的真假至少执行一次\\ 边界覆盖\quad boundary\quad coverage：每个组件的边界条件进行测试\\\end{cases}\\ 穷举测试 \end{cases} 测试技术⎩⎪⎪⎪⎪⎪⎪⎪⎪⎨⎪⎪⎪⎪⎪⎪⎪⎪⎧黑盒测试：只考虑输入和输出对应关系和程序接口，不考虑内容{划分等价类equivalenceclasspartitioning边界测试boundarytest白盒测试⎩⎪⎨⎪⎧语句覆盖statementcoverage：每个语句至少执行一次条件覆盖conditioncoverage：每个判断的真假至少执行一次边界覆盖boundarycoverage：每个组件的边界条件进行测试穷举测试

穷举测试 exhaustive test

列举出程序的所有情况，对于黑盒来说对所有输入的可能值进行测试，对于白盒来说，使测试的覆盖率达到百分之百，即每条路径的每条可能都执行一次。

需要指出的是穷举测试是不可能的，这只是一个理性情况而已。

3、Unit testing （重点）

A test point or test case is a particular choice ofinput datato be used in Test a program.

（1）Examining the code （代码审查）

⚫ Code walkthroughs

程序员向评审小组提交代码及其相关文档，然后评议小组评论其正确性。

⚫ Code inspections

与走查类似但是更正式。按照一个事先准备好的问题清单来检查代码和文档。

（2）Success of the code reviews

（3）Test thoroughness

大题必考考点********

Logic flow (*)

这个的解法很简单，就是找到所有可能走完的路径就行了。

statement

4、Integration testing（重点）

（1）Bottom-up integration

自底向上增加新模块

先测试软件最底部的各个独立组件再向上测试集成的组件。测试每一个集成的组件都要连带其下所属的底层组件一并测试一遍，即将他们看作一个整体进行测试。

需要注意的是这种测试需要为编写驱动（driver components）

In bottom-up integration test, we should develop acomponent driverto passes a test case to the component to be tested

（2）Top-down integration

测试主控模块，由桩模块代替所有直属模块

利用广度优先遍历或深度优先遍历，从根节点开始向下遍历，遍历结点的顺序就是测试的顺序。

In Top-down integration test, we write acomponentto simulate the activity of the missing component.

根据所设计的组合策略增加一个模块，设计新的桩模块

深度优先 - 先组装在软件结构的一条主控通路上的所有模块。宽度优先 - 沿软件结构水平地移动，把处于同一个控制层次上的所有模块组装起来。

（3） Big-bang integration

类似于黑盒测试，直接将所有组件组装成一个整体，对整个系统进行测试。

（4）Sandwich integration

目标层（中间层）的选择问题

混合使用自底向上和自顶向下的测试方式，先采用自顶向下测试单个组件，再利用自底向上将已测试的单个组件组装成一个整体测试。

（5）Comparison of the strategies

大题

1、If we wanted to test a positive input value, given the properly test case.

一个很大的正整数一个正整数一个正浮点数一个大于0小于1的数0负数非负的字符

3、逻辑流

statement testing：所给的test case要覆盖所有的语句，判断语句或者执行语句branche testing：若干次的branch的并集是整个集合test path：所有的路

Chapter 9 Testing the system

1、Principles of system testing（重点）

（1）Sources of software faults

（2）System testing process

（3）Configuration management

A system configuration is a collection of systemcomponentsdelivered to a particular customer.

系统配置是交付给特定用户的系统组件的集合

⚫ Versions and releases

版本和发行

⚫ Regression testing

回归测试

⚫ Deltas, separate files, and conditional compilation

细节，分离的文档，条件编译

⚫ Change control

变化控制

（4） Test team

Professional testersAnalystsSystem designerConfiguration management specialistsuser

2、Function Test

Cause-and-effect graphs

3、Performance testing

（1）Purpose and roles

（2）Types of performance testing

压力测试 stress test

不在常规条件下运行软件，而是在计算机数量较少或系统资源匮乏下测试软件的性能，通常测试的资源包括内部内存、CPU可用性、磁盘空间、网络带宽

容量测试 Volumne test

产生大量测试数据来测试软件某项指标的极限值，在给定时间内能够处理的最大负载量，从而让开发商和用户了解该软件系统的承受能力或提供服务能力。

配置测试 configuration tes

对电脑硬件的测试，通过对被测系统的软硬件环境进行调整，了解各种不同环境对系统性能的影响程度，进而找到系统各项资源的最优分配原则。

兼容性测试 compatibility test

检查软件之间能否相互正确地交流共享信息。测试内容主要为不同软件版本的兼容性；不同操作系统下软件的兼容性；新旧数据之间的兼容性等。

回归测试 regression test

回归测试是用于软件新版本的一种测试，在修改了旧代码后，重新对相同的功能进行测试，以确认修改没有引入新的错误或导致其他代码产生错误。

由于在正常情况下，对旧代码的修改往往会引入新的错误，因此回归测试的很必要的

4、Reliability, availability, and maintainability （重点）

（1）Definition

reliability

The softwarereliabilityis apossibilityof the system will operate without the failure under a givenconditionsandtimea giveninterval.

软件可靠性是指系统在给定条件和时间间隔内不发生故障运行的可能性。

Mean Time To Failure衡量：

R = MTTF/(1+MTTF)

availability

The software availability is theprobabilitythat a system is operating successfully according to specification at a givenpointof time.

软件可用性是指系统在给定的时间点按照规范成功运行的概率。

Mean Time between Faulure:MTBF

A = MTBF(1+MTBF)

maintainability

The software maintainability is the probability that , for a given condition of use, a maintenance activity can be carried out within statedtimeand using statedprocedureandresources.

软件可维护性是指在给定的使用条件下，维护活动能够在规定的时间内使用规定的程序和资源进行的概率。

Mean Time to Repair：MTTR

M = 1/(1+MTTR)

（2）Measurement

reliability

MTTF

avalibility

MTBF

maintainbility

MTTR

The test in develop environment is calledalphatest, and in customer’s environment is calledbetatest.

5、Acceptance testing

（1）Purpose and roles

（2）Types of acceptance tests

基准测试 benchmark test

由实际的用户或测试系统功能的专门小组进行测试

试点测试 pilot test

在特定的实验环境下安装测试

α测试 Alpha test

在小范围的用户内部测试，相当于内测（in-house）

β测试 Beta test

开发组发布软件，要求用户运行并提交反馈意见，即公测（out-house）

并行测试 parallel test

新旧版本系统并行运行测试

6、Installation testing

一般而言如果进行了验收测试就不需要进行安装测试了。如果在验收测试时测试环境和用户环境有较大差距，那么安装测试是有必要的。

7、Test documentation

➢ Test plan – test specification and evaluation

– test description

— test analysis report

Chapter 11 Maintaining the System

1、What is maintaining

➢ Any work done tochangethe system after it is in operation is considered to be maintenance.

The S-systems areformallydefined by and derivable from a specification.

s系统由规范正式定义并可从规范派生。

The P-system are very abstract, andimplementationis almost impractical and Impossible.

2、Four types of maintenance activities （重点）

Corrective maintenance 改正性维护

To control the day-to-day system functions, we on the maintenance team respond to problems from faults. This kind of maintenance is calledcorrectivemaintenance .