Developing Reusable Multi-Tasking Components Using Object-Oriented Techniques in Ada 95
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( 版权所有下载不究- - )第一章:课后习题:1、下列不属于Android平台的技术架构的是:Java虚拟机JVM2、下面Activity 通常就是一个单独的屏幕3、简述Android的优势:(1)系统的开放性和免费性(2)移动互联网的发展(3)相关厂商的大力支持(4)技术的进一步完善(5)开放收集联盟模式的挑战(6)其他技术的竞争本章重点:1、常见的手机操作系统:Symbian、Android、windows Mobile、IOS、OMS2、Android平台采用了软件栈,由低到高分为四部分:Linux内核层中间层(包括程序库(Libraries)和Android运行时环境)应用程序框架应用层3、一个android应用程序通常由4个组件构成:(1)活动(Activity),是最基本的android应用程序组件(2)意图(Intent),利用消息实现应用程序见的交互机制(3)服务(Service),是android应用程序中具有较长的生命周期但是没有用户界面的程序。
(4)内容提供器(Content Provider),提供了一种多应用间数据共享的方式。
其中活动(Activity)是必要部分。
第二章:课后习题:1、Activity生命周期中的(OnCreate())方法用于Activity初次创建时被调用。
2、(暂停)状态下的Activity失去了焦点,但是仍然对用户可见。
3、Activity的可见生命周期是(从调用onStart()方法到onStop()方法的整个过程)4、Android程序不能直接访问的资源存放在(assets目录)下5、简述Activity的生命周期中的各种方法。
每个Activity类在定义是都必须继承android.app.Activity(1)onCreate():Activity初次创建时被调用,在该方法中一般进行一些静态设置,如创建View视图,进行数据绑定。
如果Activity是首次创建,本方法后将会调用onStart(),如果Activity是停止后重新显示,则调用onRestart()。
毕业论文论文题目:基于Android的背单词软件的设计与实现毕业设计(论文)原创性声明和使用授权说明原创性声明本人郑重承诺:所呈交的毕业设计(论文),是我个人在指导教师的指导下进行的研究工作及取得的成果。
尽我所知,除文中特别加以标注和致谢的地方外,不包含其他人或组织已经发表或公布过的研究成果,也不包含我为获得及其它教育机构的学位或学历而使用过的材料。
对本研究提供过帮助和做出过贡献的个人或集体,均已在文中作了明确的说明并表示了谢意。
作者签名:日期:指导教师签名:日期:使用授权说明本人完全了解大学关于收集、保存、使用毕业设计(论文)的规定,即:按照学校要求提交毕业设计(论文)的印刷本和电子版本;学校有权保存毕业设计(论文)的印刷本和电子版,并提供目录检索与阅览服务;学校可以采用影印、缩印、数字化或其它复制手段保存论文;在不以赢利为目的前提下,学校可以公布论文的部分或全部内容。
作者签名:日期:学位论文原创性声明本人郑重声明:所呈交的论文是本人在导师的指导下独立进行研究所取得的研究成果。
除了文中特别加以标注引用的内容外,本论文不包含任何其他个人或集体已经发表或撰写的成果作品。
对本文的研究做出重要贡献的个人和集体,均已在文中以明确方式标明。
本人完全意识到本声明的法律后果由本人承担。
作者签名:日期:年月日学位论文版权使用授权书本学位论文作者完全了解学校有关保留、使用学位论文的规定,同意学校保留并向国家有关部门或机构送交论文的复印件和电子版,允许论文被查阅和借阅。
本人授权大学可以将本学位论文的全部或部分内容编入有关数据库进行检索,可以采用影印、缩印或扫描等复制手段保存和汇编本学位论文。
涉密论文按学校规定处理。
作者签名:日期:年月日导师签名:日期:年月日注意事项1.设计(论文)的内容包括:1)封面(按教务处制定的标准封面格式制作)2)原创性声明3)中文摘要(300字左右)、关键词4)外文摘要、关键词5)目次页(附件不统一编入)6)论文主体部分:引言(或绪论)、正文、结论7)参考文献8)致谢9)附录(对论文支持必要时)2.论文字数要求:理工类设计(论文)正文字数不少于1万字(不包括图纸、程序清单等),文科类论文正文字数不少于1.2万字。
基于java的视频会议系统设计与实现重庆大学工程硕士论文学生姓名:***指导教师:***兼职导师:***工程领域:软件工程重庆大学软件学院年月Design and Implementation of Java-Based Video Conference SystemA Thesis Submitted to Chongqing Universityin Partial Fulfillment of the Requirement for theDegree of Master of EngineeringBy***Supervised by Prof. ***Supervised by Associate-Prof. ***Specialty: Software EngineeringCollege of Software Engineering of ChongqingUniversity, Chongqing, China摘要随着互联网的发展与进步,网络与计算机应用已经普及到社会的各个层面。
对于一个逐渐壮大的集团化企业来说,高效的管理模式和工作方式,直接影响着其在市场竞争中的地位。
某集团(全称:某集团有限公司)下辖18个分/子公司、污水处理厂及项目部,集团总部或在分支机构召开的各种办公会议,不仅花费了大量的时间和经费,也给公司管理带来很大的不便。
因此,必须有一种新的会议方式,解决某集团公司面临的,会议多、效率低的现实问题。
笔者作为某集团信息部员工,在深入调研后,提出开发视频会议系统的方案,并参与了系统需求分析、设计、实现、项目管理等全过程。
该方案详细论述了利用Java相关技术,开发基于SIP协议视频会议系统的详细过程。
本文的研究工作包括两大部分:(1)利用SIP协议完成信令的多点呼叫控制,从而实现对会议的管理。
(2)利用RTP协议和Java相关技术实现多媒体的通信。
通过本系统的研发取得了以下几个方面的成果:(1)视频会议服务器端,其实现的主要功能包括:主持会议、操控会议、结束会议;客户端,其主要功能是参加会议、参与文件管理等操作。
基于多Agent的软件开发研究一、引言随着人工智能技术的发展,多Agent技术逐渐成为了软件开发中的热点研究领域。
多Agent技术通过将软件系统划分成多个Agent,从而提高软件系统的可靠性、安全性和效率等方面的性能。
本文将探讨基于多Agent的软件开发研究及其应用。
二、多Agent技术1.多Agent技术概述Agent是指一个具有自主决策能力和交互能力的实体,能够自主地完成某些任务。
而多Agent技术则是指将多个独立的Agent组成一个协同的智能系统,通过相互之间的协作和交互完成复杂的任务。
在多Agent系统中,每个Agent都有自己的目标和行为,并且能够通过与其他Agent进行通信、协作和竞争来实现自己的目标。
2.多Agent系统的关键技术多Agent系统的关键技术包括分布式问题求解技术、Agent通信协议、Agent知识表示和推理技术、Agent协作技术等。
其中,分布式问题求解技术是多Agent系统的核心技术之一,它能够将一个大规模的问题分解成多个小规模的子问题,然后分配给不同的Agent进行求解,从而提高问题的求解效率和质量。
三、基于多Agent的软件开发研究1.多Agent系统在软件开发中的应用目前,多Agent技术已经在软件开发中得到了广泛的应用,例如在电子商务、智能交通、人工智能等领域都有着重要的应用。
在这些领域中,多Agent技术能够通过增加系统的智能性和灵活性,提高系统的性能和可靠性。
2.基于多Agent的软件开发流程基于多Agent的软件开发流程包括需求分析、Agent设计、Agent实现、Agent测试和系统集成等阶段。
在需求分析阶段,需要根据用户需求和系统目标确定系统架构和Agent组成;在Agent 设计阶段,需要对每个Agent进行建模并设计Agent之间的通信协议;在Agent实现阶段,需要根据Agent设计完成Agent的编程和实现;在Agent测试阶段,需要对每个Agent进行单元测试和集成测试;最后在系统集成阶段,需要将所有Agent进行集成测试和调试以实现系统的稳定运行。
中南大学设计模式实验2实验2 设计模式实验一实验学时: 4每组人数: 1实验类型: 3 (1:基础性 2:综合性 3:设计性 4:研究性)实验要求: 1 (1:必修 2:选修 3:其它)实验类别: 3 (1:基础 2:专业基础 3:专业 4:其它)一、实验目的1.熟练使用面向对象设计原则对系统进行重构;2.熟练使用PowerDesigner和任意一种面向对象编程语言实现几种常见的创建型设计模式和结构型设计模式,包括简单工厂模式、工厂方法模式、抽象工厂模式、单例模式、适配器模式、桥接模式和组合模式,理解每一种设计模式的模式动机,掌握模式结构,学习如何使用代码实现这些模式。
二、实验内容1.在某图形库API中提供了多种矢量图模板,用户可以基于这些矢量图创建不同的显示图形,图形库设计人员设计的初始类图如下所示:Circle+ + + + +init ()setColor ()fill ()setSize ()display ()...: void: void: void: void: voidTriangle+++++init ()setColor ()fill ()setSize ()display ()...: void: void: void: void: voidRectangle+++++init ()setColor ()fill ()setSize ()display ()...: void: void: void: void: voidClient在该图形库中,每个图形类(如Circle、Triangle等)的init()方法用于初始化所创建的图形, setColor()方法用于给图形设置边框颜色,fill()方法用于给图形设置填充颜色,setSize()方法用于设置图形的大小,display()方法用于显示图形。
客户类(Client)在使用该图形库时发现存在如下问题:①由于在创建窗口时每次只需要使用图形库中的一种图形,因此在更换图形时需要修改客户类源代码;②在图形库中增加并使用新的图形时需要修改客户类源代码;③客户类在每次使用图形对象之前需要先创建图形对象,有些图形的创建过程较为复杂,导致客户类代码冗长且难以维护。
通用学术英语(技能篇)_西安交通大学中国大学mooc课后章节答案期末考试题库2023年1.The following claim is against which dimension of the ARS triangle?Claim: The college entrance examination(高考) in China should be banned because my friend told me that the validity of the exam is weak.答案:Acceptability2.Which logic dose the following reasoning belong to?Fact 1: The victims of cyber bullying are emotionally upset.Fact 2: The victims of cyber bullying are likely to withdraw from family members and friends.Fact 3: The victims of cyber bullying may avoid school or groupgathering.Conclusion: Cyber bullying is harmful.答案:Induction.3.We can use a startling fact, an emotional example and a quote from areliable source to start a cause and effect essay.Do you think thestatement is true or false?答案:True.4.Which of the following description is from the perspective ofconsequences ?答案:Those who suffer from procrastination(拖延症)are likely to cram from a task.5.Suppose that you are listening to a lecture. You heard that “In theprevious lecture, we have talked about how mammals giving birth to babies. Today, we are going to discuss …” What functions do thesesentences have?答案:Review of the previous lecture and topic today.6.Do you think the following statement is true or false ?Statement: An abstract of a research article can be regarded as asummary.答案:True.7.Which of the following is true about the organizational patterns of acontrast essay ?答案:The point-by-point pattern is essential if your material is complicated.8.What are the two strategies that you adopt to identify similarities anddifferences of subject ?答案:Venn diagram and table.9.Which of the following is NOT true in terms of the structure of aresearch article ?答案:The four sections (IMRD) are the only components in a research article.10.Which of the following is NOT true in terms of the major information ineach section of a research article ?答案:Researchers usually explains thoroughly the findings they obtained in theResults section.11.Things are classified into different categories in a tree structure, orpossibly a forest structure. What type of classification does it belong to ?答案:Hierarchical classification.12.Read the original sentence (below) and decide which paraphrase (1 to 3) isthe best.Throughout most of the developed world, universities have seen a steadyincrease in the number of women enrolling in engineering courses.答案:The number of women studying engineering at university has been rising steadily in the majority of developed countries.13.If you are reading the introduction part of a chapter, what do you thinkthe chapter is about?Team work is vital in business. A plan must be developed for dividingwork among the members of the management team. Each member must be given enough authority to be able to accomplish the assigned talk.Moreover, for the greatest efficiency the authority of each member must be expanded by various means.答案:Ways to expand each member's authority.14.Which of the following is a good paraphrase for the sentence below:The car industry began in France and Germany, but took off in theUnited States.答案:France and Germany initiated the car industry, which was later accelerated in the United States.15. In ARS triangle, A refers to acceptability, R stands for relevance, S is theacronym of ______.答案:sufficiency16.Which of the following is a FACT ?答案:Hummingbirds are the only bird that can fly backwards.17.From which aspect does the following sentence extend the definition?“A population is the number of living things that live together in the same place. The world population was estimated to have reached 7.5 billion in April 2017. Asia is the most populous continent, with its 4.3 billion inhabitants being 60% of the world population.”答案:Examples.18.Which strategy is the following note possibly employing?答案:Mapping.19.The table shows the number of school days each month during the lastschool year.Which of the graphs best represents the data?答案: Graph 2.20.If a lecturer talks about the following content in his lecture: camouflage,mobbing, running away, chemical weapons of animals on the topic“How animals protect themselves”, which of the following is thepossible organization of the lecture?答案:Classification.21.You and your classmate are having a discussion in class. If your partnerasks “What do you mean by phototropism? ”, what type of question does it belong to?答案:Asking for clarification.22.What is the communicative function of the following sentence in 3MT?Now historians have tended to use adults' reflective sources such asautobiographies to tell us about childhood, but I argue that we really need touse and hear the children's voices. So I use hundreds of evacuee letters in my work.答案:Methods23.What is the communicative function of the following sentence in 3MT?The big question that we want to know is how effective are these readingprograms for these struggling readers, considering their limited resources.答案:Termination。
重构方法(1)- 提取方法描述:当你的代码中有一些片段在逻辑上能够归为一组,那么通常可以将这一组代码提取出来形成一个方法,并用方法名来解释方法的目的。
动机:1.提高了其他方法重用这段代码的可能性。
2.使得‘高层’的方法可读性更好。
3.当有需要的时候,重载更加方便。
步骤:1.创建一个新方法,以方法的目的为该方法命名(而不是以方法的具体行为为该方法命名)。
2.把要提取的方法从原来的方法中拷贝到新方法中。
3.检查提取的代码,看看其中是否有对原来方法中的局部变量的引用(通常IDE会帮我们做,会用编译错误来提示找不到变量)。
如果有,将该变量作为方法的参数。
4.检查在原方法中是否有只在提取的代码中使用的临时变量,如果有,将该变量移入提取的方法中。
5.看看在第三步中的局部变量在方法中是否被改变了。
如果只有一个局部变量被改变,那么我们可以将该变量作为方法的返回值返回。
如果有多于一个的变量被改变,那么我们可能需要先进行'分离临时变量'(另外一种重构方法,以后介绍)重构,再进行提取方法的重构。
我们以可以使用'使用查询方法代替临时变量'(另外一种重构方法,以后介绍)来减少临时变量的个数。
6.编译代码,看看是否有错误。
7.用提取的方法替换原来方法中被提取的代码。
注意在原方法中删除第四步中我们移入的临时变量。
8.编译,运行单元测试。
例子:1. 没有局部变量的情况1.void printOwing(){2. Enumeration e = _orders.elements();3. double outstanding = 0.0;4.5.6.7. //打印提示信息8.System.out.println(“************************”);9.System.out.println(“***** Customer10.Owes *****”);11.System.out.println(“************************”);12.13.14.15. //计算应付金额16. while (e.hasMoreElements()) {17. Order each = (Order) e.nextElement();18. outstanding += each.getAmount();19. }20.21.22.23. //打印详细信息24.System.out.println(“name:” +25._name);26.System.out.println(“amount:” +27.outstanding);28.}复制代码在这里,我们可以很容易的将打印提示信息的部分代码提取成单独的方法。
南开21春学期(1709-2103)《手机应用软件设计与实现》在线作业提示:南开大学课程学习已经开启,本套试卷是课程学习辅导资料,只作参考学习使用!!!一、单选题 (共 30 道试题,共 60 分)1.使用Android系统进行拍照用到的类有:A.SurfaceViewB.SurfaceHolderC.CallbackD.Camera[提问:仔细分析上述试题,并从选项中选择一项,填写在答题卡上]参考答案是:D2.在开发AppWidget窗口小部件时, 需要继承()类A.A,AppWidgetReceiverB.B,AppWidgetConfigureC.C,AppWidgetManagerD.D,AppWidgetProvider[提问:仔细分析上述试题,并从选项中选择一项,填写在答题卡上]参考答案是:D3.在Android应用程序中,图片应放在那个目录下A.rawB.valuesyoutD.drawable[提问:仔细分析上述试题,并从选项中选择一项,填写在答题卡上]参考答案是:D4.对于一个Activity,在AndroidManifest.xml中对他这样进行定义,这样的描述代表什么含义A.无明确含义,每个Activity都需要这样定义B.代表该Activity将作为程序的主Activity,并且在LAUNCHER菜单中启动C.代表该Activity将在桌面上建立图标并启动D.代表该Activity的优先级高于其他的Activity[提问:仔细分析上述试题,并从选项中选择一项,填写在答题卡上]参考答案是:B5.下面关于Linux内核描述错误的是A.由于Linux内核全部使用Java语言编写,故Android的Linux内核层也全部是用Java 语言编写的。
B.Linux是一个开源的操作系统,由非营利的组织——Linux基金会所管理。
C.Android的内核属于Linux内核的一个分支。
D.目前,Android的Linux内核层包括安全管理、内存管理、进程管理、网络协议栈、驱动程序模型和电源管理等。
一、Introduction(入门)0、Introduction to Android(引进到Android)Android provides a rich application framework that allows you to build innovative apps and games for mobile devices in a Java language environment. The documents listed in the left navigation provide details about how to build apps using Android's various APIs.To learn how apps work, startwith App Fundamentals.To begin coding right away, read Building Your First AppAndroid提供了丰富的应用程序框架,它允许您在Java语言环境中构建移动设备的创新应用程序和游戏。
在左侧导航中列出的文档提供了有关如何使用Android的各种API来构建应用程序的详细信息。
要了解如何开发应用,从应用基础开始。
如何开始一个正确的编码,请参照建立你的第一个应用程序。
Apps provide multiple entry points 应用程序提供多个入口点Apps adapt to different devices 应用程序适应不同的设备Android apps are built as a combination of distinct components that can be invoked individually. For instance, an individual activity provides a single screen for a user interface, and a service independently performs work in the background.Android应用程序被构建为能够单独地被调用不同的部件的组合。
Developing Reusable Multi-Tasking ComponentsUsing Object-Oriented Techniques in Ada 95
Patrick de Bondeli14 Boulevard Jean Mermoz92200 Neuilly-s-Seine, FranceEMail : bondeli@pobox.oleane.com1. IntroductionSince 1985, we have undertaken extensive works onconcurrent system development methodology and theirsystematic implementation in Ada. In 1990-1991, thisresulted in the presentation of the CODE-TOP(COncurrent system DEvelopment using TransformationsOf Predicate-transition nets) methodology [1][2]. Startingfrom this basis, we later developed a framework ofcomponents, using OO techniques, which are reusable toimplement in Ada 95 any type exporting synchronization/ communication properties [3].
This leads us to propose, as a theme for this workshop,the identification, development, and implementation inAda 95 of general purpose reusable components forconcurrent systems. By "general purpose", we mean thatthese components are not specialized in any specificdomain as, for example, communication, or guidance andcontrol systems. This proposal enters perfectly within thegoals that were stated in the "Call for Participation" and ismore specifically related to the two following goals : ."Identify the benefits and impacts of using object-oriented programming in multi-tasking real-timesystems"; ."Explore the use of Ada 95 in developing multi-tasking components that are resilient to software designerrors and hardware failures".
In section 2, we briefly expose the state of our works,which we already quoted.
In section 3, we propose to consider the differentpossible kinds of reusable multi-tasking components inAda 95. On one kind of components our works could be agood starting point for discussion.
2. The Present State of Our Works in theArea of Reusable Components forConcurrent Systems
If we consider the general model of asynchronousprocesses communicating throughsynchronization/communication objects, this modelimplies a partitioning of systems in three categories ofobjects : Active objects (processes), having their ownthread of control, synchronization/communicationobjects, and purely passive objects which are to be usedby a single process.
Our mentioned work was concerned in developingreusable components for the two first categories ofobjects.
Components for building active objects wereconsidered only in the CODE-TOP study [1][2] andimplemented in Ada 83. These components included a
number of (formally defined) models of processactivation, either through explicit operations, or byasynchronous interrupts (in this latter case, dynamicattachment/detachment operations were also included)and their implementation in Ada 83. The implementationin Ada 95 should be made a lot simpler and more flexibleby the new possibilities of referencing task objects andthe new interrupt model.
The CODE-TOP study also lead to the development ofa methodology for (formally) specifying andimplementing in Ada 83 any type ofsynchronization/communication objects. The frameworkof components presented in [3] is reusable to implementin Ada 95 any type of synchronization / communicationfrom its CODE-TOP style of formal specification. Anannex to the present paper gives further detail on it. Weattempted to maximize the reusability of this frameworkby making a full use of object-oriented features of Ada 95(tagged types, class-wide programming, hierarchicallibrary units) and we found an interesting way (havingmore general applicability than those proposed in [4]) forimplementing the mix of extensibility and concurrencyproperties which it exports.
3. The Different Kinds of Reusable Multi-Tasking Components which We CouldConsider
3.1. Considering the Sole "AsynchronousCommunicating Process" Model
A first item of discussion could be reusablecomponents to build synchronization/communicationobjects.The discussion on this item could be introduced by apresentation of the framework of Ada 95 components thatwe have developed for this purpose and which is brieflydescribed in the annex to this paper. Such matters asdomain (synchronization/communication) analysis,architectural and implementation choices could beconsidered in this discussion.
A second item of discussion could be active objectsand the process activation operations : Are Ada 95 (corelanguage plus system and real-time annexes) primitives tobe directly used, or is there some room for a higher levelset of reusable components in this area?