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Java毕业设计外文翻译

Java毕业设计外文翻译

毕业设计(论文)外文文献翻译译文:Java I/O 系统[1]对编程语言的设计者来说,创建一套好的输入输出(I/O)系统,是一项难度极高的任务。

这一类可以从解决方案的数量之多上看出端倪。

这个问题就难在它要面对的可能性太多了。

不仅是因为有那么多的I/O的源和目的(文件,控制台,网络连接等等),而且还有很多方法(顺序的,随机的,缓存的,二进制的,字符方式的,行的,字的等等)。

Java类库的设计者们用“创建很多类”的办法来解决这个问题。

坦率地说,Java I/O系统的类实在太多了,以至于初看起来会把人吓着(但是,具有讽刺意味的是,这种设计实际上是限制了类的爆炸性增长)。

此外,Java在1.0版之后又对其I/O类库进行了重大的修改,原先是面向byte的,现在又补充了面向Unicode字符的类库。

为了提高性能,完善功能,JDK1.4又加了一个nio(意思是“new I/O”。

这个名字会用上很多年)。

这么以来,如果你想对Java 的I/O类库有个全面了解,并且做到运用自如,你就得先学习大量的类。

此外,了解I/O类库的演化历史也是相当重要的。

可能你的第一反应是“别拿什么历史来烦我了,告诉我怎么用就可以了!”但问题是,如果你对这段一无所知,很快就会被一些有用或是没用的类给搞糊涂了。

本文会介绍Java 标准类库中的各种I/O类,及其使用方法。

File 类在介绍直接从流里读写数据的类之前,我们先介绍一下处理文件和目录的类。

你会认为这是一个关于文件的类,但它不是。

你可以用它来表示某个文件的名字,也可以用它来表示目录里一组文件的名字。

如果它表示的是一组文件,那么你还可以用list( )方法来进行查询,让它会返回String数组。

由于元素数量是固定的,因此数组会比容器更好一些。

如果你想要获取另一个目录的清单,再建一个File对象就是了。

目录列表器假设你想看看这个目录。

有两个办法。

一是不带参数调用list( )。

它返回的是File对象所含内容的完整清单。

JAVA外文文献+翻译

JAVA外文文献+翻译

Java and the InternetIf Java is, in fact, yet another computer programming language, you may question why it is so important and why it is being promoted as a revolutionary step in computer programming. The answer isn’t immediately obvious if you’re coming from a traditional programming perspective. Although Java is very useful for solving traditional stand-alone programming problems, it is also important because it will solve programming problems on the World Wide Web.1.Client-side programmingThe Web’s initial server-browser design provided for interactive content, but the interactivity was completely provided by the server. The server produced static pages for the client browser, which would simply interpret and display them. Basic HTML contains simple mechanisms for data gathering: text-entry boxes, check boxes, radio boxes, lists and drop-down lists, as well as a button that can only be programmed to reset the data on the form or “submit” the data on the form back to the server. This submission passes through the Common Gateway Interface (CGI) provided on all Web servers. The text within the submission tells CGI what to do with it. The most common action is to run a program located on the server in a directory that’s typically called “cgi-bin.” (If you watch the address window at the top of your browser when you push a button on a Web page, you can sometimes see “cgi-bin” within all the gobbledygook there.) These programs can be written in most languages. Perl is acommon choice because it is designed for text manipulation and is interpreted, so it can be installed on any server regardless of processor or operating system. Many powerful Web sites today are built strictly on CGI, and you can in fact do nearly anything with it. However, Web sites built on CGI programs can rapidly become overly complicated to maintain, and there is also the problem of response time. The response of a CGI program depends on how much data must be sent, as well as the load on both the server and the Internet. (On top of this, starting a CGI program tends to be slow.) The initial designers of the Web did not foresee how rapidly this bandwidth would be exhausted for the kinds of applications people developed. For example, any sort of dynamic graphing is nearly impossible to perform with consistency because a GIF file must be created and moved from the server to the client for each version of the graph. And you’ve no doubt had direct experience with something as simple as validating the data on an input form. You press the submit button on a page; the data is shipped back to the server; the server starts a CGI program that discovers an error, formats an HTML page informing you of the error, and then sends the page back to you; you must then back up a page and try again. Not only is this slow, it’s inelegant.The solution is client-side programming. Most machines that run Web browsers are powerful engines capable of doing vast work, and with the original static HTML approach they are sitting there, just idly waiting for the server to dish up the next page. Client-side programming means that the Web browser is harnessed to do whatever work it can, and the result for the user is a much speedier and more interactive experience at your Web site.The problem with discussions of client-side programming is that they aren’t very different from discussions of programming in general. The parameters are almost the same, but the platform is different: a Web browser is like a limited operating system. In the end, you must still program, and this accounts for the dizzying array of problems and solutions produced by client-side programming. The rest of this section provides an overview of the issues and approaches in client-side programming.2.Plug-insOne of the most significant steps forward in client-side programming is the development of the plug-in. This is a way for a programmer to add new functionality to the browser by downloading a piece of code that plugs itself into the appropriate spot in the browser. It tells the browser “from now on you can perform this new activity.” (You ne ed to download the plug-in only once.) Some fast and powerful behavior is added to browsers via plug-ins, but writing a plug-in is not a trivial task, and isn’t something you’d want to do as part of the process of building a particular site. The value of the plug-in for client-side programming is that it allows an expert programmer to develop a new language and add that language to a browser without the permission of the browser manufacturer. Thus, plug-ins provide a “back door” that allows the creation of new client-side programming languages (although not all languages are implemented as plug-ins).3.Scripting languagesPlug-ins resulted in an explosion of scripting languages. With a scripting language you embed the source code for your client-side program directly into the HTML page, and the plug-in that interprets that language is automatically activated while the HTML page is being displayed. Scripting languages tend to be reasonably easy to understand and, because they are simply text that is part of an HTML page, they load very quickly as part of the single server hit required to procure that page. The trade-off is that your code is exposed for everyone to see (and steal). Generally, however, you aren’t doing amazingly sophisticated things with scripting languages so this is not too much of a hardship.This points out that the scripting languages used inside Web browsers are really intended to solve specific types of problems, primarily the creation of richer and more interactive graphical user interfaces (GUIs). However, a scripting language might solve 80 percent of the problems encountered in client-side programming. Your problems might very well fit completely withinthat 80 percent, and since scripting languages can allow easier and faster development, you should probably consider a scripting language before looking at a more involved solution such as Java or ActiveX programming.The most commonly discussed browser scripting languages are JavaScript (which has nothing to do with Java; it’s named that way just to grab some of Java’s marketing momentum), VBScript (which looks like Visual Basic), and Tcl/Tk, which comes from the popular cross-platform GUI-building language. There are others out there, and no doubt more in development.JavaScript is probably the most commonly supported. It comes built into both Netscape Navigator and the Microsoft Internet Explorer (IE). In addition, there are probably more JavaScript books available than there are for the other browser languages, and some tools automatically create pages using JavaScript. However, if you’re already fluent in Visual Basic or Tcl/Tk, you’ll be more productive using those scripting languages rather than learning a new one. (You’ll have your hands full dealing with the Web issues already.)4.JavaIf a scripting language can solve 80 percent of the client-side programming problems, what about the other 20 percent—the “really hard stuff?” The most popular solution today is Java. Not only is it a powerful programming language built to be secure, cross-platform, and international, but Java is being continually extended to provide language features and libraries that elegantly handle problems that are difficult in traditional programming languages, such as multithreading, database access, network programming, and distributed computing. Java allows client-side programming via the applet.An applet is a mini-program that will run only under a Web browser. The applet is downloaded automatically as part of a Web page (just as, for example, a graphic is automatically downloaded). When the applet is activated it executes a program. This is part of its beauty—it provides you with a way to automatically distribute the client software from the server at the time the user needs the client software, and no sooner. The user gets the latest version of the client software without fail and without difficult reinstallation. Because of theway Java is designed, the programmer needs to create only a single program, and that program automatically works with all computers that have browsers with built-in Java interpreters. (This safely includes the vast majority of machines.) Since Java is a full-fledged programming language, you can do as much work as possible on the client before and after making requests of the server. F or example, you won’t need to send a request form across the Internet to discover that you’ve gotten a date or some other parameter wrong, and your client computer can quickly do the work of plotting data instead of waiting for the server to make a plot and ship a graphic image back to you. Not only do you get the immediate win of speed and responsiveness, but the general network traffic and load on servers can be reduced, preventing the entire Internet from slowing down.One advantage a Java applet has ove r a scripted program is that it’s in compiled form, so the source code isn’t available to the client. On the other hand, a Java applet can be decompiled without too much trouble, but hiding your code is often not an important issue. Two other factors can be important. As you will see later in this book, a compiled Java applet can comprise many modules and take multiple server “hits” (accesses) to download. (In Java 1.1 and higher this is minimized by Java archives, called JAR files, that allow all the required modules to be packaged together and compressed for a single download.) A scripted program will just be integrated into the Web page as part of its text (and will generally be smaller and reduce server hits). This could be important to the responsiveness of your Web site. Another factor is the all-important learning curve. Regardless of what you’ve heard, Java is not a trivial language to learn. If you’re a Visual Basic programmer, moving to VBScript will be your fastest solution, and since it will probably solve most typical client/server problems you might be hard pressed to justify learning Java. If you’re experienced with a scripting language you will certainly benefit from looking at JavaScript or VBScript before committing to Java, since they might fit your needs handily and you’ll be more productive sooner.to run its applets withi5.ActiveXTo some degree, the competitor to Java is Microsoft’s ActiveX, although it takes a completely different approach. ActiveX was originally a Windows-only solution, although it is now being developed via an independent consortium to become cross-platform. Effectively, ActiveX says “if your program connects to its environment just so, it can be dropped into a Web page and run under a browser that supports ActiveX.” (I E directly supports ActiveX and Netscape does so using a plug-in.) Thus, ActiveX does not constrain you to a particular language. If, for example, you’re already an experienced Windows programmer using a language such as C++, Visual Basic, or Borland’s Del phi, you can create ActiveX components with almost no changes to your programming knowledge. ActiveX also provides a path for the use of legacy code in your Web pages.6.SecurityAutomatically downloading and running programs across the Internet can sound like a virus-builder’s dream. ActiveX especially brings up the thorny issue of security in client-side programming. If you click on a Web site, you might automatically download any number of things along with the HTML page: GIF files, script code, compiled Java code, and ActiveX components. Some of these are benign; GIF files can’t do any harm, and scripting languages are generally limited in what they can do. Java was also designed to run its applets within a “sandbox” of safety, which prevents it from wri ting to disk or accessing memory outside the sandbox.ActiveX is at the opposite end of the spectrum. Programming with ActiveX is like programming Windows—you can do anything you want. So if you click on a page that downloads an ActiveX component, that component might cause damage to the files on your disk. Of course, programs that you load onto your computer that are not restricted to running inside a Web browser can do the same thing. Viruses downloaded from Bulletin-Board Systems (BBSs) have long been a problem, but the speed of the Internet amplifies the difficulty.The solution seems to be “digital signatures,” whereby code is verified to show who the author is. This is based on the idea that a virus works because its creator can be anonymous, so if you remove the anonymity individuals will be forced to be responsible for their actions. This seems like a good plan because it allows programs to be much more functional, and I suspect it will eliminate malicious mischief. If, however, a program has an unintentional destructive bug it will still cause problems.The Java approach is to prevent these problems from occurring, via the sandbox. The Java interpreter that lives on your local Web browser examines the applet for any untoward instructions as the applet is being loaded. In particular, the applet cannot write files to disk or erase files (one of the mainstays of viruses). Applets are generally considered to be safe, and since this is essential for reliable client/server systems, any bugs in the Java language that allow viruses are rapidly repaired. (It’s worth noting that the browser software actually enforces these security restrictions, and some browsers allow you to select different security levels to provide varying degrees of access to your system.) You might be skeptical of this rather draconian restriction against writing files to your local disk. For example, you may want to build a local database or save data for later use offline. The initial vision seemed to be that eventually everyone would get online to do anything important, but that was soon seen to be impractical (although low-cost “Internet appliances” might someday satisfy the needs of a significant segment of users). The solution is the “signed applet” that uses public-key encryption to verify that an applet does indeed come from where it claims it does. A signed applet can still trash your disk, but the theory is that since you can now hold the applet creator accountable they won’t do vicious things. Java provides a framework for digital signatures so that you will eventually be able to allow an applet to step outside the sandbox if necessary. Digital signatures have missed an important issue, which is the speed that people move around on the Internet. If you download a buggy program and it does something untoward, how long will it be before you discover the damage? It could be days or even weeks. By then, how will you track down the program that’s done it? And what good will it do you at that point?7.Internet vs. intranetThe Web is the most general solution to the client/server problem, so it makes sense that you can use the same technology to solve a subset of the problem, in particular the classic client/server problem within a company. With traditional client/server approaches you have the problem of multiple types of client computers, as well as the difficulty of installing new client software, both of which are handily solved with Web browsers and client-side programming. When Web technology is used for an information network that is restricted to a particular company, it is referred to as an intranet. Intranets provide much greater security than the Internet, since you can physically control access to the servers within your company. In terms of training, it seems that once people und erstand the general concept of a browser it’s much easier for them to deal with differences in the way pages and applets look, so the learning curve for new kinds of systems seems to be reduced.The security problem brings us to one of the divisions that seems to be automatically forming in the world of client-side programming. If your program is running on the Internet, you don’t know what platform it will be working under, and you want to be extra careful that you don’t disseminate buggy code. You need something cross-platform and secure, like a scripting language or Java.If you’re running on an intranet, you might have a different set of constraints. It’s not uncommon that your machines could all be Intel/Windows platforms. On an intranet, you’re respon sible for the quality of your own code and can repair bugs when they’re discovered. In addition, you might already have a body of legacy code that you’ve been using in a more traditional client/server approach, whereby you must physically install client programs every time you do an upgrade. The time wasted in installing upgrades is the most compelling reason to move to browsers, because upgrades are invisible and automatic. If you are involved in such an intranet, the most sensible approach to take is the shortest path that allows you to use your existing code base, rather than trying to recode your programs in a new language.When faced with this bewildering array of solutions to the client-side programming problem, the best plan of attack is a cost-benefit analysis. Consider the constraints of your problem and what would be the shortest path to your solution. Since client-side programming is still programming, it’s always a good idea to take the fastest development approach for your particular situation. This is an aggressive stance to prepare for inevitable encounters with the problems of program development.8.Server-side programmingThis whole discussion has ignored the issue of server-side programming. What happens when you make a request of a server? Most of the time the request is simply “send me this file.” Your browser then interprets the file in some appropriate fashion: as an HTML page, a graphic image, a Java applet, a script program, etc. A more complicated request to a server generally involves a database transaction. A common scenario involves a request for a complex database search, which the server then formats into an HTML page and sends to you as the result. (Of course, if the client has more intelligence via Java or a scripting language, the raw data can be sent and formatted at the client end, which will be faster and less load on the server.) Or you might want to register your name in a database when you join a group or place an order, which will involve changes to that database. These database requests must be processed via some code on the server side, which is generally referred to as server-side programming. Traditionally, server-side programming has been performed using Perl and CGI scripts, but more sophisticated systems have been appearing. These include Java-based Web servers that allow you to perform all your server-side programming in Java by writing what are called servlets. Servlets and their offspring, JSPs, are two of the most compelling reasons that companies who develop Web sites are moving to Java, especially because they eliminate the problems of dealing with differently abled browsers.9. separate arena: applicationsMuch of the brouhaha over Java has been over applets. Java is actually a general-purpose programming language that can solve any type of problem—at least in theory. And as pointed out previously, there might be more effective ways to solve most client/server problems. When you move out of the applet arena (and simultaneously release the restrictions, such as the one against writing to disk) you enter the world of general-purpose applications that run standalone, without a Web browser, just like any ordinary program does. Here, Java’s strength is not only in its portability, but also its programmability. As you’l l see throughout this book, Java has many features that allow you to create robust programs in a shorter period than with previous programming languages. Be aware that this is a mixed blessing. You pay for the improvements through slower execution speed (although there is significant work going on in this area—JDK 1.3, in particular, introduces the so-called “hotspot” performance improvements). Like any language, Java has built-in limitations that might make it inappropriate to solve certain types of programming problems. Java is a rapidly evolving language, however, and as each new release comes out it becomes more and more attractive for solving larger sets of problems.Java和因特网既然Java不过另一种类型的程序设计语言,大家可能会奇怪它为什么值得如此重视,为什么还有这么多的人认为它是计算机程序设计的一个里程碑呢?如果您来自一个传统的程序设计背景,那么答案在刚开始的时候并不是很明显。

JAVA外文文献翻译

JAVA外文文献翻译

J A V A外文文献翻译Last revision on 21 December 2020中文翻译基于Java技术的Web应用设计模型的比较研究来源:School of Computer Science and Engineering University of New South Wales Sydney, NSW 2052, Australia作者:Budi Kurniawan and Jingling Xue摘要Servlet技术是在建立可扩展性Web应用中被应用最广泛的技术。

在运用JAVA技术开发Web应用中有四种模型,分别是:Model 1、Model 2、Struts和JavaServer Faces JSF。

Model 1使用一连串的JSP页面,Model 2采用了模型,视图,控制器MVC模式。

Struts是一个采用了Model 2设计模型的框架,JSF是一种支持ready-to-use组件来进行快速Web应用开发的新技术。

Model 1对于中等和大型的应用来说很难维护,所以不推荐使用。

本文通过利用Model 2、Struts和JSF这三种模型分别构建三个不同版本的在线商店应用程序来比较和评价这三种模型在应用程序开发和性能上的差异。

1.绪论当今Web应用是一种展现动态内容的最普遍的方式。

构建Web应用有许多种方法,其中最流行的是Servlet技术。

这种技术的流行是因为它比CGI、PHP等其他技术更具优越性。

然而Servlet对于开发来说还是麻烦的,因为它在传送HTML标签时需要程序员将他们组合成为一个字符串对象,再将这个对象传给浏览器。

同样的,对于输出的一个很小的改动也要求Servlet被重新编译。

基于这个原因SUN公司发明了JavaServer Pages JSP技术。

JSP允许HTML标签和Java代码混合在一起,每个页面将被转化为一个Servlet,一个JSP就是一个Servlet,而且编译将在JSP页面第一次被请求时自动进行改变输出也不需要重新编译。

网页制作外文文献及翻译

网页制作外文文献及翻译

网页制作Dreamweaver外文文献及翻译Dreamweaver 3.0 is the newest version of Dreamweaver-a tool for compiling web pages, introduced by Macromedia Company. Its feature is "what you see is what you get"-this is really a blessing for novice. Also, it has functions for web site management, facilitating design and management of multiple web sites. Fig. 1 is the interface when Dreamweaver 3. 0 is activated.1. A Brief Introduction of Dream weaverCompared with its predecessor Dreamweaver 2.0, Dreamweaver3.0 is more friendly and practical for use in its operating interface, and its function has been further improved. Readers will see it is so easy to create web pages, without writing any page of code to rapidly create dynamic HTML web pages, for example, cartoon and layers; and by using its object browser, it is also possible to create web pages applicable to various platforms and browsers with very good compatibility; and it is also possible to make use of Roundtrip HTML technology provided by Dreamweaver to control the source code generated by Dreamweaver with high precision.More significantly, Dreamweaver provides you with individualized space. Your can create your own object and command, revise menu and quick keys, or even create you own JavaScript to expand Dreamweaver. It is not exaggerated at all that Dreamweaver brings in unlimited space for you to create your web pages.2. A General Description of Dreamweaver Functions(1) documents foundation and useThe documents operation is the homepage manufacture foundation. Dreamweaver not only may found the blank documents and based on the template documents, but also may edit the HTML document which in other procedures founds, for example FrontPage and so on. Dream weaver has also provided the history (History) the kneading board. The historical kneading board has recorded the reader the history which operates in the documents window, it may help you to abolish or the repetition step, and greatly simplified the homepage manufacture process. Chart 2 has demonstrated one demonstration history kneading board method.* Joins the picture and the super linkA homepage only has the text is unable to attract the person, must in the documents China and Canada person other elements. The picture certainly is inevitable, form and ultra link also essential, is abundant can suffice fascinatingly.Dream weaver provided two kinds to insert the person picture the way. The reader may choose the menu to order Insert/Image; Also may select The super link is in the documents the most important part. Had it to be allowed freely to jump from a position to another weaver formidable function has provided the many kinds of links way possibility. The mostcommon link is between the documents link, this regarding Dream weaver said certainly is a cinch. Also may found the special link using Dream weaver, for example uses the E-Mail linking the homepage, in order to promptly gains the outside each kind of feedback information, this regarding a good website said is extremely important. Also may found the script link, moves the corresponding JavaScript script, thus realizes the corresponding operation.*Website managementThe website management is the Dream weaver essence are partial. Using Dream weaver, may facilitate quickly establishes the local website and the far-end website. Dream weaver may help user's to duplicate far-end server on far-end website on the local computer, constitution local website; Also may duplicate the local website on the far-end server, constitution far-end website. Dream weaver can maintain between the local website and far-end website content synchronization, guaranteed the user carries on the renewal with wishes fulfilled to the far-end website. It also may carry on the test to in the website link, discovers break and the mistake, and carries on the repair, guarantees the website structure the accuracy.Dynamic homepage manufactureThe newest standard HTML 4.0 languages the original will expand some brand-new domains, turned the true abbreviation will be DHTML). But JavaScript and the CSS language is in function formidable DHTML the most main part. CSS and the JavaScript coordination use, may extremely simply realize the homepage dynamic effect.(2) Dream weaver 3.0 new functionsDream the weaver 3.0 new characteristics strengthened the function, improved the website management, the permission user increase navigation fence (Navigation Bar), the picture map (Images Maps) and so on the element, causes the work flow, the user and expands Dream weaver.(a) HTML edition functionFast label editorCauses the user not to need to leave Dream the weaver documents window to be allowed fast to revise, the increase, to move the HTML label.HTML styleIn 3.0 may use the standard HTML label in Dream weaver which the multi- browsers supports to found the style (for instance label and label), but in the before edition, only could use the level to fold the style list (CSS).(c) Founds and the edition object and the page elementThe user may be allowed with ease to obtain the commonly used object in the object kneading board. 1662。

计算机java外文翻译外文文献英文文献

计算机java外文翻译外文文献英文文献

英文原文:Title: Business Applications of Java. Author: Erbschloe, Michael, Business Applications of Java -- Research Starters Business, 2008DataBase: Research Starters - BusinessBusiness Applications of JavaThis article examines the growing use of Java technology in business applications. The history of Java is briefly reviewed along with the impact of open standards on the growth of the World Wide Web. Key components and concepts of the Java programming language are explained including the Java Virtual Machine. Examples of how Java is being used bye-commerce leaders is provided along with an explanation of how Java is used to develop data warehousing, data mining, and industrial automation applications. The concept of metadata modeling and the use of Extendable Markup Language (XML) are also explained.Keywords Application Programming Interfaces (API's); Enterprise JavaBeans (EJB); Extendable Markup Language (XML); HyperText Markup Language (HTML); HyperText Transfer Protocol (HTTP); Java Authentication and Authorization Service (JAAS); Java Cryptography Architecture (JCA); Java Cryptography Extension (JCE); Java Programming Language; Java Virtual Machine (JVM); Java2 Platform, Enterprise Edition (J2EE); Metadata Business Information Systems > Business Applications of JavaOverviewOpen standards have driven the e-business revolution. Networking protocol standards, such as Transmission Control Protocol/Internet Protocol (TCP/IP), HyperText Transfer Protocol (HTTP), and the HyperText Markup Language (HTML) Web standards have enabled universal communication via the Internet and the World Wide Web. As e-business continues to develop, various computing technologies help to drive its evolution.The Java programming language and platform have emerged as major technologies for performing e-business functions. Java programming standards have enabled portability of applications and the reuse of application components across computing platforms. Sun Microsystems' Java Community Process continues to be a strong base for the growth of the Java infrastructure and language standards. This growth of open standards creates new opportunities for designers and developers of applications and services (Smith, 2001).Creation of Java TechnologyJava technology was created as a computer programming tool in a small, secret effort called "the Green Project" at Sun Microsystems in 1991. The Green Team, fully staffed at 13 people and led by James Gosling, locked themselves away in an anonymous office on Sand Hill Road in Menlo Park, cut off from all regular communications with Sun, and worked around the clock for18 months. Their initial conclusion was that at least one significant trend would be the convergence of digitally controlled consumer devices and computers. A device-independent programming language code-named "Oak" was the result.To demonstrate how this new language could power the future of digital devices, the Green Team developed an interactive, handheld home-entertainment device controller targeted at the digital cable television industry. But the idea was too far ahead of its time, and the digital cable television industry wasn't ready for the leap forward that Java technology offered them. As it turns out, the Internet was ready for Java technology, and just in time for its initial public introduction in 1995, the team was able to announce that the Netscape Navigator Internet browser would incorporate Java technology ("Learn about Java," 2007).Applications of JavaJava uses many familiar programming concepts and constructs and allows portability by providing a common interface through an external Java Virtual Machine (JVM). A virtual machine is a self-contained operating environment, created by a software layer that behaves as if it were a separate computer. Benefits of creating virtual machines include better exploitation of powerful computing resources and isolation of applications to prevent cross-corruption and improve security (Matlis, 2006).The JVM allows computing devices with limited processors or memory to handle more advanced applications by calling up software instructions inside the JVM to perform most of the work. This also reduces the size and complexity of Java applications because many of the core functions and processing instructions were built into the JVM. As a result, software developersno longer need to re-create the same application for every operating system. Java also provides security by instructing the application to interact with the virtual machine, which served as a barrier between applications and the core system, effectively protecting systems from malicious code.Among other things, Java is tailor-made for the growing Internet because it makes it easy to develop new, dynamic applications that could make the most of the Internet's power and capabilities. Java is now an open standard, meaning that no single entity controls its development and the tools for writing programs in the language are available to everyone. The power of open standards like Java is the ability to break down barriers and speed up progress.Today, you can find Java technology in networks and devices that range from the Internet and scientific supercomputers to laptops and cell phones, from Wall Street market simulators to home game players and credit cards. There are over 3 million Java developers and now there are several versions of the code. Most large corporations have in-house Java developers. In addition, the majority of key software vendors use Java in their commercial applications (Lazaridis, 2003).ApplicationsJava on the World Wide WebJava has found a place on some of the most popular websites in the world and the uses of Java continues to grow. Java applications not only provide unique user interfaces, they also help to power the backend of websites. Two e-commerce giants that everybody is probably familiar with (eBay and Amazon) have been Java pioneers on the World Wide Web.eBayFounded in 1995, eBay enables e-commerce on a local, national and international basis with an array of Web sites-including the eBay marketplaces, PayPal, Skype, and -that bring together millions of buyers and sellers every day. You can find it on eBay, even if you didn't know it existed. On a typical day, more than 100 million items are listed on eBay in tens of thousands of categories. Recent listings have included a tunnel boring machine from the Chunnel project, a cup of water that once belonged to Elvis, and the Volkswagen that Pope Benedict XVI owned before he moved up to the Popemobile. More than one hundred million items are available at any given time, from the massive to the miniature, the magical to the mundane, on eBay; the world's largest online marketplace.eBay uses Java almost everywhere. To address some security issues, eBay chose Sun Microsystems' Java System Identity Manager as the platform for revamping its identity management system. The task at hand was to provide identity management for more than 12,000 eBay employees and contractors.Now more than a thousand eBay software developers work daily with Java applications. Java's inherent portability allows eBay to move to new hardware to take advantage of new technology, packaging, or pricing, without having to rewrite Java code ("eBay drives explosive growth," 2007).Amazon (a large seller of books, CDs, and other products) has created a Web Service application that enables users to browse their product catalog and place orders. uses a Java application that searches the Amazon catalog for books whose subject matches a user-selected topic. The application displays ten books that match the chosen topic, and shows the author name, book title, list price, Amazon discount price, and the cover icon. The user may optionally view one review per displayed title and make a buying decision (Stearns & Garishakurthi, 2003).Java in Data Warehousing & MiningAlthough many companies currently benefit from data warehousing to support corporate decision making, new business intelligence approaches continue to emerge that can be powered by Java technology. Applications such as data warehousing, data mining, Enterprise Information Portals (EIP's), and Knowledge Management Systems (which can all comprise a businessintelligence application) are able to provide insight into customer retention, purchasing patterns, and even future buying behavior.These applications can not only tell what has happened but why and what may happen given certain business conditions; allowing for "what if" scenarios to be explored. As a result of this information growth, people at all levels inside the enterprise, as well as suppliers, customers, and others in the value chain, are clamoring for subsets of the vast stores of information such as billing, shipping, and inventory information, to help them make business decisions. While collecting and storing vast amounts of data is one thing, utilizing and deploying that data throughout the organization is another.The technical challenges inherent in integrating disparate data formats, platforms, and applications are significant. However, emerging standards such as the Application Programming Interfaces (API's) that comprise the Java platform, as well as Extendable Markup Language (XML) technologies can facilitate the interchange of data and the development of next generation data warehousing and business intelligence applications. While Java technology has been used extensively for client side access and to presentation layer challenges, it is rapidly emerging as a significant tool for developing scaleable server side programs. The Java2 Platform, Enterprise Edition (J2EE) provides the object, transaction, and security support for building such systems.Metadata IssuesOne of the key issues that business intelligence developers must solve is that of incompatible metadata formats. Metadata can be defined as information about data or simply "data about data." In practice, metadata is what most tools, databases, applications, and other information processes use to define, relate, and manipulate data objects within their own environments. It defines the structure and meaning of data objects managed by an application so that the application knows how to process requests or jobs involving those data objects. Developers can use this schema to create views for users. Also, users can browse the schema to better understand the structure and function of the database tables before launching a query.To address the metadata issue, a group of companies (including Unisys, Oracle, IBM, SAS Institute, Hyperion, Inline Software and Sun) have joined to develop the Java Metadata Interface (JMI) API. The JMI API permits the access and manipulation of metadata in Java with standard metadata services. JMI is based on the Meta Object Facility (MOF) specification from the Object Management Group (OMG). The MOF provides a model and a set of interfaces for the creation, storage, access, and interchange of metadata and metamodels (higher-level abstractions of metadata). Metamodel and metadata interchange is done via XML and uses the XML Metadata Interchange (XMI) specification, also from the OMG. JMI leverages Java technology to create an end-to-end data warehousing and business intelligence solutions framework.Enterprise JavaBeansA key tool provided by J2EE is Enterprise JavaBeans (EJB), an architecture for the development of component-based distributed business applications. Applications written using the EJB architecture are scalable, transactional, secure, and multi-user aware. These applications may be written once and then deployed on any server platform that supports J2EE. The EJB architecture makes it easy for developers to write components, since they do not need to understand or deal with complex, system-level details such as thread management, resource pooling, and transaction and security management. This allows for role-based development where component assemblers, platform providers and application assemblers can focus on their area of responsibility further simplifying application development.EJB's in the Travel IndustryA case study from the travel industry helps to illustrate how such applications could function. A travel company amasses a great deal of information about its operations in various applications distributed throughout multiple departments. Flight, hotel, and automobile reservation information is located in a database being accessed by travel agents worldwide. Another application contains information that must be updated with credit and billing historyfrom a financial services company. Data is periodically extracted from the travel reservation system databases to spreadsheets for use in future sales and marketing analysis.Utilizing J2EE, the company could consolidate application development within an EJB container, which can run on a variety of hardware and software platforms allowing existing databases and applications to coexist with newly developed ones. EJBs can be developed to model various data sets important to the travel reservation business including information about customer, hotel, car rental agency, and other attributes.Data Storage & AccessData stored in existing applications can be accessed with specialized connectors. Integration and interoperability of these data sources is further enabled by the metadata repository that contains metamodels of the data contained in the sources, which then can be accessed and interchanged uniformly via the JMI API. These metamodels capture the essential structure and semantics of business components, allowing them to be accessed and queried via the JMI API or to be interchanged via XML. Through all of these processes, the J2EE infrastructure ensures the security and integrity of the data through transaction management and propagation and the underlying security architecture.To consolidate historical information for analysis of sales and marketing trends, a data warehouse is often the best solution. In this example, data can be extracted from the operational systems with a variety of Extract, Transform and Load tools (ETL). The metamodels allow EJBsdesigned for filtering, transformation, and consolidation of data to operate uniformly on datafrom diverse data sources as the bean is able to query the metamodel to identify and extract the pertinent fields. Queries and reports can be run against the data warehouse that contains information from numerous sources in a consistent, enterprise-wide fashion through the use of the JMI API (Mosher & Oh, 2007).Java in Industrial SettingsMany people know Java only as a tool on the World Wide Web that enables sites to perform some of their fancier functions such as interactivity and animation. However, the actual uses for Java are much more widespread. Since Java is an object-oriented language like C++, the time needed for application development is minimal. Java also encourages good software engineering practices with clear separation of interfaces and implementations as well as easy exception handling.In addition, Java's automatic memory management and lack of pointers remove some leading causes of programming errors. Most importantly, application developers do not need to create different versions of the software for different platforms. The advantages available through Java have even found their way into hardware. The emerging new Java devices are streamlined systems that exploit network servers for much of their processing power, storage, content, and administration.Benefits of JavaThe benefits of Java translate across many industries, and some are specific to the control and automation environment. For example, many plant-floor applications use relatively simple equipment; upgrading to PCs would be expensive and undesirable. Java's ability to run on any platform enables the organization to make use of the existing equipment while enhancing the application.IntegrationWith few exceptions, applications running on the factory floor were never intended to exchange information with systems in the executive office, but managers have recently discovered the need for that type of information. Before Java, that often meant bringing together data from systems written on different platforms in different languages at different times. Integration was usually done on a piecemeal basis, resulting in a system that, once it worked, was unique to the two applications it was tying together. Additional integration required developing a brand new system from scratch, raising the cost of integration.Java makes system integration relatively easy. Foxboro Controls Inc., for example, used Java to make its dynamic-performance-monitor software package Internet-ready. This software provides senior executives with strategic information about a plant's operation. The dynamic performance monitor takes data from instruments throughout the plant and performs variousmathematical and statistical calculations on them, resulting in information (usually financial) that a manager can more readily absorb and use.ScalabilityAnother benefit of Java in the industrial environment is its scalability. In a plant, embedded applications such as automated data collection and machine diagnostics provide critical data regarding production-line readiness or operation efficiency. These data form a critical ingredient for applications that examine the health of a production line or run. Users of these devices can take advantage of the benefits of Java without changing or upgrading hardware. For example, operations and maintenance personnel could carry a handheld, wireless, embedded-Java device anywhere in the plant to monitor production status or problems.Even when internal compatibility is not an issue, companies often face difficulties when suppliers with whom they share information have incompatible systems. This becomes more of a problem as supply-chain management takes on a more critical role which requires manufacturers to interact more with offshore suppliers and clients. The greatest efficiency comes when all systems can communicate with each other and share information seamlessly. Since Java is so ubiquitous, it often solves these problems (Paula, 1997).Dynamic Web Page DevelopmentJava has been used by both large and small organizations for a wide variety of applications beyond consumer oriented websites. Sandia, a multiprogram laboratory of the U.S. Department of Energy's National Nuclear Security Administration, has developed a unique Java application. The lab was tasked with developing an enterprise-wide inventory tracking and equipment maintenance system that provides dynamic Web pages. The developers selected Java Studio Enterprise 7 for the project because of its Application Framework technology and Web Graphical User Interface (GUI) components, which allow the system to be indexed by an expandable catalog. The flexibility, scalability, and portability of Java helped to reduce development timeand costs (Garcia, 2004)IssueJava Security for E-Business ApplicationsTo support the expansion of their computing boundaries, businesses have deployed Web application servers (WAS). A WAS differs from a traditional Web server because it provides a more flexible foundation for dynamic transactions and objects, partly through the exploitation of Java technology. Traditional Web servers remain constrained to servicing standard HTTP requests, returning the contents of static HTML pages and images or the output from executed Common Gateway Interface (CGI ) scripts.An administrator can configure a WAS with policies based on security specifications for Java servlets and manage authentication and authorization with Java Authentication andAuthorization Service (JAAS) modules. An authentication and authorization service can bewritten in Java code or interface to an existing authentication or authorization infrastructure. Fora cryptography-based security infrastructure, the security server may exploit the Java Cryptography Architecture (JCA) and Java Cryptography Extension (JCE). To present the user with a usable interaction with the WAS environment, the Web server can readily employ a formof "single sign-on" to avoid redundant authentication requests. A single sign-on preserves user authentication across multiple HTTP requests so that the user is not prompted many times for authentication data (i.e., user ID and password).Based on the security policies, JAAS can be employed to handle the authentication process with the identity of the Java client. After successful authentication, the WAS securitycollaborator consults with the security server. The WAS environment authentication requirements can be fairly complex. In a given deployment environment, all applications or solutions may not originate from the same vendor. In addition, these applications may be running on different operating systems. Although Java is often the language of choice for portability between platforms, it needs to marry its security features with those of the containing environment.Authentication & AuthorizationAuthentication and authorization are key elements in any secure information handling system. Since the inception of Java technology, much of the authentication and authorization issues have been with respect to downloadable code running in Web browsers. In many ways, this had been the correct set of issues to address, since the client's system needs to be protected from mobile code obtained from arbitrary sites on the Internet. As Java technology moved from a client-centric Web technology to a server-side scripting and integration technology, it required additional authentication and authorization technologies.The kind of proof required for authentication may depend on the security requirements of a particular computing resource or specific enterprise security policies. To provide such flexibility, the JAAS authentication framework is based on the concept of configurable authenticators. This architecture allows system administrators to configure, or plug in, the appropriate authenticatorsto meet the security requirements of the deployed application. The JAAS architecture also allows applications to remain independent from underlying authentication mechanisms. So, as new authenticators become available or as current authentication services are updated, system administrators can easily replace authenticators without having to modify or recompile existing applications.At the end of a successful authentication, a request is associated with a user in the WAS user registry. After a successful authentication, the WAS consults security policies to determine if the user has the required permissions to complete the requested action on the servlet. This policy canbe enforced using the WAS configuration (declarative security) or by the servlet itself (programmatic security), or a combination of both.The WAS environment pulls together many different technologies to service the enterprise. Because of the heterogeneous nature of the client and server entities, Java technology is a good choice for both administrators and developers. However, to service the diverse security needs of these entities and their tasks, many Java security technologies must be used, not only at a primary level between client and server entities, but also at a secondary level, from served objects. By using a synergistic mix of the various Java security technologies, administrators and developers can make not only their Web application servers secure, but their WAS environments secure as well (Koved, 2001).ConclusionOpen standards have driven the e-business revolution. As e-business continues to develop, various computing technologies help to drive its evolution. The Java programming language and platform have emerged as major technologies for performing e-business functions. Java programming standards have enabled portability of applications and the reuse of application components. Java uses many familiar concepts and constructs and allows portability by providing a common interface through an external Java Virtual Machine (JVM). Today, you can find Java technology in networks and devices that range from the Internet and scientific supercomputers to laptops and cell phones, from Wall Street market simulators to home game players and credit cards.Java has found a place on some of the most popular websites in the world. Java applications not only provide unique user interfaces, they also help to power the backend of websites. While Java technology has been used extensively for client side access and in the presentation layer, it is also emerging as a significant tool for developing scaleable server side programs.Since Java is an object-oriented language like C++, the time needed for application development is minimal. Java also encourages good software engineering practices with clear separation of interfaces and implementations as well as easy exception handling. Java's automatic memory management and lack of pointers remove some leading causes of programming errors. The advantages available through Java have also found their way into hardware. The emerging new Java devices are streamlined systems that exploit network servers for much of their processing power, storage, content, and administration.中文翻译:标题:Java的商业应用。

计算机 JSP web 外文翻译 外文文献

计算机 JSP web 外文翻译 外文文献

计算机 JSP web 外文翻译外文文献12.1 nEffective web n design involves separating business objects。

n。

and object XXX。

Although one individual may handle both roles on a small-scale project。

it is XXX.12.2 JSP ArchitectureIn this chapter。

XXX using JavaServer Pages。

servlets。

XXX of different architectures。

each building upon the us one。

The diagram below outlines this process。

and we will explain each component in detail later in this article.Note: XXX.)When Java Server Pages were introduced by Sun。

some people XXX。

While JSP is a key component of the J2EE n and serves as the preferred request handler and response mechanism。

it is XXX.XXX JSP。

the XXX that JSP is built on top of the servlet API and uses servlet XXX interesting ns。

such as whether we should XXX in our Web-enabled systems。

and if there is a way to combine servlets and JSPs。

网页设计专业毕业设计外文翻译

网页设计专业毕业设计外文翻译

Produce the design of the tool and realize automaticallyon the basis of JSP webpageIt is an important respect that Internet uses that Web develops technology, and JSP is the most advanced technology that Web is developed , it is present Web developer's first-selected technology. But because JSP has relatively high expectations for Web developer, a lot of general Web developers can not use this advanced technology . The discussion produces the design of the tool and realizes automatically on the basis of JSP webpage of the template and label storehouse, put forward concrete design philosophy and implementation method .With the popularization of WWW (World Wide Web ), the technology of the dynamic webpage is developed rapidly too. From original CGI (Common Gateway In-terface ) to ASP (Active Server Page ), have met the webpage developer to the demand for developing technology of the dynamic webpage to a certain extent. But no matter CGI or ASP have certain limitation, for instance, consuming to resources of the server of CGI, ASP can only be used etc. with Microsoft IIS, all these have limited scope of application of the technology, have hindered their popularization greatly. The vast page developers all look forward to a kind of unified page and develop technology earnestly, characteristic that this technology there should be:①Have nothing to do with the operating platform, can run on any Web or the application program server ;②Show the logic and page of application program that separates ; ③Offer codes to put in an position, simplify and develop the course based on interactive application program of Web.JSP (Java Server Page ) technology is designed and used for responding to the request that like this. JSP is developed technology by the new webpage that Sun MicroSystem Company put out in June of 1999, it is that Web based on Java Serv-let and the whole Java system develops technology, and Servlet2. Expansion of 1API. Utilize this technology, can set up advancedly , safely and stepping dynamic websites of the platform .Java is the future mainstream to develop technology , have a lot of advantages . JSP is Java important application technology on Internet/Intranet Web , get extensive support and admit, it can conbine with various kinds of Java technology together intactly , thus realize very complicated application.As a kind of technology of development based on text , taking showing as centre, JSP has offered all advantages of Java Servlet. Logic function in order to make sure and showing the function was separated , JSP can already work with JavaBeans , Enterprise JavaBeans (EJB ) and Servlet . The developer of JSP can finish the work that majority and website's logic are correlated with through using JavaBeans , EJB and Servlet , and only assign the work shown to JSP page to finish. Content and show advantage that logic separate lie in , upgrade person , page of appearanceneedn't understand Java code , the personnel upgrading Javas needn't be experts who design webpage either. This can define Web template in JSP page with Javas , in order to set up websites made up of a page with similar appearance. Java completion data offer, have Java code among template, this mean template these can write by one HTML person is it maintain to come.JSP develops technology as the webpage of the mainstream at present, has the following characteristics:(1) Separate the formulation and showing of the content : Using JSP technology, the page developer of Web can use HTML or XML identification to design and format the final page . Use JSP identification or bound foot turn into dynamic content of page actually (whether content according to is it come change to ask). Produce logic of content of the identification and JavaBeans package , truss up of the little script encapsulation, all scripts run in the end of the server. If key logic among identification and JavaBeans, then other people, such as Web administrative staff and page designer encapsulation, can edit and use JSP page , and does not influence the formulation of the content .(2) Emphasize the reusable package : Most JSP pages depend on the reusable one, the package stepping the platform finish more complicated treatment with required application program. Benefitting from the independence of operating platform of Java, the developer can be very convenient to share and exchange and carry out the ordinary package that operated, or make these packages used by more users. The method based on package has accelerated the total development course, the efficiency of improving the project and developing wholly greatly.Though JSP is powerful, it requires the webpage developer should be quite familiar with Java. There are still relatively few Java programmers now, for general webpage developer, the grammar of JSP is more difficult to grasp . So, need a kind of webpage developing instrument and offer commonly used JSP application to general webpage developer, is it understand general page develop developer of technology (HTML ) can use strong function of JSP too only to let.Systematic design object and main technology of use:(1)Design objectSystem this design object for understand but HTML understand general webpage developer of JSP offer a webpage developing instrument at all only, enable them to follow the systematic file, use the daily function of JSP through the label, produce one finally and only include static HTML and dynamic JSP webpage of JSP label.(2)Main technologyThis system is in the design, consider using the technology of the template and JSP label to realize mainly.1、Technology of the templateThe technology of the template is widely applied to various kinds of development and application system. It produces some commonly used frame structure in advance , uses the family to choose the template from the template storehouse conveniently according to the needs of one's own one, is it is it put up to go again by oneself to need , save construction period in user , facilitate use of user. In this system , classify the page according to the function type , sum up the commonly used page type, produce the template storehouse.2、Storehouse technology of the labelIn JSP, movements can create and visit the language target of the procedure and influence the element exported and flowed. JSP has defined six standard movements. Except six standard movement these, user can define own movement finish the specific function. These movements are known as the customer movement, they are the reusable procedure module . Through movement these, programmer can some encapsulation stand up too display function of page in JSP page, make the whole page more succinct and easier to maintain. In a JSP page, movements were transfered through the customer label in these customers. And the label storehouse (Tag Library ) is the set of the customer label.JSP label storehouse is that one kind produces the method based on script of XML through JavaBeans. It is one of the greatest characteristics of JSP. Through the label storehouse , can expand JSP application unrestrictedly , finish any complicated application demand.JSP label storehouse has the following characteristic:①Easy to use: The labels in JSP and general HTML marks are totally the same in appearance, it is as convenient as ordinary HTML mark to use.②The easy code is paid most attention to: Every label in the label storehouse can finish certain function . Define ready to eat one label storehouse , is it pack one Jar file the label storehouse to need only, then only need use this label storehouse in other systems afterwards, needn't develop codes again , has raised the system and developed efficiency greatly, have reduced the development cost.③The easy code is safeguarded: All application logic is encapsulated in label processor and JavaBeans, all labels concentrate on a label storehouse. If need to upgrade codes or need to revise the function on a webpage, only need to revise the corresponding label. Maintain way in unison through this kind , it is unnecessary in each webpage is it is it fix to act as to get onning, have reduce the work load safeguarded greatly, has economized the cost of safeguarding.④The easy system is expanded : If need to add the new function to the system , only need to define a new label to finish this function, do not need to do any change to other respects of thesystem. Can inherit JSP normal characteristics of various fields in the label storehouse. Can expand and increase the function of JSP unrestrictedly like this, and does not need to wait for the appearance of the next edition JSP .Systematic composition and realizing:(1)The system making upThis system is made up of four parts mainly:1、The database joins some: This system supports several daily databases , including Oracle, Sybase, MSSQLServer, MySQL and DB2, use JDBC and database to link to each other according to database type and database name , user name , password that users offer that users choose.2、The basic form of system produces some: After joining with the database , produce the basic form TC-Tables and TC-Columns of two systems according to the user name linking to each other with the database , TC-Tables form includes English name , Chinese name and some attribute of form belonging to this user in this database , for instance can revise , can inquire about ; The Chinese and English name of the row and some other attribute that TC-Columns form includes belonging to all forms of this user's in this database . For instance can show , can inquire about . Basic information of the database that these basic forms of two systems provide to user's institute for use in the course of development of the whole system.3、The template is chosen to produce some with the webpage: This part is a key part of a system. It includes two pieces of sub module .①The template is chosen some: The system offers the template to user and chooses the interface, let users choose the templates used from the template storehouse according to the need.②The template is dealt with some: According to template that user choose, system transfer designated template deal with module is it punish to go on to these template. When dealing with the label that the procedure meets in the template, offer the mutual interface to user, let user input parameter for designated label , prove system validity of label that user input. Finished the formulation of JSP page systematically finally.Webpage preview is with revising some: After the webpage was produced out, the system has offered a webpage preview window and code to user and looked over that revises the window. Through this preview window, users can look at the result of JSP page produced out in advance . If user static result of respect in page very satisfied, user can through code look over revise window revise HTML code of code. If users have further demands for the static result of the page, the system has also offered a piece of interface which transfers DreamWeaver editing machine to user, users can use it to carry on further modification and perfection to the static result of JSP page that is produced out .(2)Systematic realization1、Realization of the template storehouse and label storehouseThe planning and design of the label storehouse are essential in the whole system design, efficiency that the degree and system that are put in an position have operated that its relation has reached codes. Its planning should follow the following principle .(1) Should try one's best little including static HTML among label. To general user, the label is transparent. Users can not look over and revise labels . If include too many static HT-ML sentence in the label , will influence the modification and perfection of user's static result to the page, limit the use of the label.(2) Try one's best to raise the paying most attention to degree of the code. Is it is it is it is it is it is it get to JSP public JSP out to withdraw to use to try one's best to classify to go on to use, form labels. Do not use and realize this application repeatedly in each label . While revising and perfecting to using like this , only need to revise this label, maintenance of the easy code.(3) Facilitate users' use. While designing the label storehouse , should fully consider users' operating position , it can very easy and understanding and using labels conveniently to use the family.①Definition of the label storehouse: Define a label storehouse, must define a label storehouse and describe the file (TLD ) at first . This is a file of script based on XML, have defined the edition of XML in this file , codes used, the edition , name and definition and parameter of all labels included in this storehouse of the label storehouse of the edition of the label storehouse , JSP used describe, including the name of the label, corresponding Javas of label, description information of the label ,etc..②Realization of the label: One label first special Java type, this each must inherit TagSupports , this each is in javax. servlet. jsp. Define in tagext bag . In the labels, the parameter which includes this label initializes the subject treatment method (Handler ) of method (Set/Get ) , label and method available for making the first class label to adjust,etc..③Realization of the template : A template is that one contains JSP file that labels quoted . In order to quote the labels defined in the template , must introduce the label storehouse at first .<%@taglib uri=“tag.tld”prefix=“ctag”%>Among them uri appoints the label storehouse to describe the route of the file ; Prefixes used when prefix appoints to quote labels.While quoting the designated label in the template , use the designated prefix while introducing the label storehouse, appoint the name of the label; It is the parameter assignment of the label.2、Systematic development environmentWhat this systematic subject procedure making is used is JBuilder 6 of Borland Company. 0, it is Front-Page2000 of Microsoft Company that the template is developed and used, what the label storehouse is developed and used is UltraEdit editing machine, what JDK is adopted is JDK1.4. The system testing environment is JRun3. 0.Java future mainstream to develop language, and Java using JSP will become major technology that Web will be developed in the future too mainly at Web. This system has adopted the label storehouse , one of the biggest characteristics of JSP, enable the general Web developer to use JSP strong dynamic page function conveniently too, develop JSP dynamic Web page of the modern techniques. Because this system adopts Java to develop, can run under the operating system of any support graphic interface , have realized complete having nothing to do with the platform. This system is easy to expand and perfect. Can consider offering the interface to user afterwards , will use the family to expand the template storehouse and label storehouse by oneself, strengthen the systematic function further.List of references:[1] Cay S. Horstmann,Gary Cornell. Java 2 key technology (CoreJava 2 ) [M ]. Beijing: Publishing house of the mechanical industry.[2] Bruce Eckel. Java programming thought (Thinking in Java ) [M ]. Beijing: Publishing house of the mechanical industry.[3] Joseph L. Weber. Java 2 programming is explained in detail (Using Java 2) [M ]. Beijing: Electronic Industry Press.[4] Borland Company. Building Applications with JBuilder.基于JSP网页自动生成工具的设计与实现Web开发技术是Internet应用的一个重要方面,而JSP又是Web开发的最先进的技术,是当前Web开发人员的首选技术。

JAVA毕业设计外文文献翻译

JAVA毕业设计外文文献翻译

THE TECHNIQUE DEVELOPMENT HISTORY OF JSPBy:Kathy Sierra and Bert BatesSource: Servlet&JSPThe Java Server Pages( JSP) is a kind of according to web of the script plait distance technique, similar carries the script language of Java in the server of the Netscape company of server- side JavaScript( SSJS) and the Active Server Pages(ASP) of the Microsoft. JSP compares the SSJS and ASP to have better can expand sex, and it is no more exclusive than any factory or some one particular server of Web. Though the norm of JSP is to be draw up by the Sun company of, any factory can carry out the JSP on own system.The After Sun release the JS P( the Java Server Pages) formally, the this kind of new Web application development technique very quickly caused the people's concern. JSP provided a special development environment for the Webapplication that establishes the high dynamic state. According to the Sun parlance, the JSP can adapt to include the Apache WebServer, IIS4.0 on themarket at inside of 85% server product.This chapter will introduce the related knowledge of JSP and Databases, and JavaBean related contents, is all certainly rougher introduction among them basic contents, say perhaps to is a Guide only, if the reader needs the more detailed information, pleasing the book of consult the homologous JSP.1.1 GENER ALIZEThe JSP(Java Server Pages) is from the company of Sun Microsystems initiate, the many companies the participate to the build up the together of the a kind the of dynamic the state web the page technique standard, the it have the it in the construction the of the dynamic state the web page the strong but the do not the especially of the function. JSP and the technique of ASP of the Microsoft is very alike. Both all provide the ability that mixes with a certain procedure code and is explain by the language engine to carry out the procedure code in the code of HTML. Underneath we are simple of carry on the introduction to it.JSP pages are translated into servlets. So, fundamentally, any task JSP pages can perform could also be accomplished by servlets. However, this underlying equivalence does not mean that servlets and JSP pages are equally appropriatein all scenarios. The issue is not the power of the technology, it is the convenience, productivity, and maintainability of one or the other. After all, anything you can do on a particular computer platform in the Java programming language you could also do in assembly language. But it still matters which youchoose.JSP provides the following benefits over servlets alone: • It is easier to write and maintain the HTML. Your static code is ordinary HTML: no extra backslashes, no double quotes, and no lurking Java syntax.• You can use standard Web-site development tools. Even HTML tools that know nothing about JSP can be used because they simply ignore the JSP tags. • You can divide up your development team. The Java programmers can work on the dynamic code. The Web developers can concentrate on the presentation layer. On large projects, this division is very important. Depending on the size of your team and the complexity of your project, you can enforce a weaker or stronger separation between the static HTML and the dynamic content. Now, this discussion is not to say that you should stop using servlets and use only JSP instead. By no means. Almost all projects will use both. For some requests in your project, you will use servlets. For others, you will use JSP. For still others, you will combine them with the MVC architecture . You want the apGFDGpropriate tool for the job, and servlets, by themselves, do not completeyour toolkit.1.2 SOURCE OF JSPThe technique of JSP of the company of Sun, making the page of Web develop the personnel can use the HTML perhaps marking of XML to design to turn the end page with format. Use the perhaps small script future life of marking of JSP becomes the dynamic state on the page contents.( the contents changesaccording to the claim of)The Java Servlet is a technical foundation of JSP, and the large Web applies the development of the procedure to need the Java Servlet to match with with the JSP and then can complete, this name of Servlet comes from the Applet, the local translation method of now is a lot of, this book in order not to misconstruction, decide the direct adoption Servlet but don't do any translation, if reader would like to, can call it as" small service procedure". The Servlet is similar to traditional CGI, ISAPI, NSAPI etc. Web procedure development the function of the tool in fact, at use the Java Servlet hereafter, the customer neednot use again the lowly method of CGI of efficiency, also need not use only the ability come to born page of Web of dynamic state in the method of API that a certain fixed Web server terrace circulate. Many servers of Web all support the Servlet, even not support the Servlet server of Web directly and can also pass the additional applied server and the mold pieces to support the Servlet. Receive benefit in the characteristic of the Java cross-platform, the Servlet is also a terrace irrelevant, actually, as long as match the norm of Java Servlet, the Servlet is complete to have nothing to do with terrace and is to have nothing to do with server of Web. Because the Java Servlet is internal to provide the service by the line distance, need not start a progress to the each claimses, and make use of the multi-threading mechanism can at the same time for several claim service, therefore the efficiency of Java Servlet is very high.But the Java Servlet also is not to has no weakness, similar to traditional CGI, ISAPI, the NSAPI method, the Java Servlet is to make use of to output the HTML language sentence to carry out the dynamic state web page of, if develop the whole website with the Java Servlet, the integration process of the dynamic state part and the static state page is an evil-foreboding dream simply. For solving this kind of weakness of the Java Servlet, the SUN released the JSP.A number of years ago, Marty was invited to attend a small 20-person industry roundtable discussion on software technology. Sitting in the seat next to Marty was James Gosling, inventor of the Java programming language. Sitting several seats away was a high-level manager from a very large software company in Redmond, Washington. During the discussion, the moderator brought up the subject of Jini, which at that time was a new Java technology. The moderator asked the manager what he thought of it, and the manager responded that it was too early to tell, but that it seemed to be an excellent idea. He went on to say that they would keep an eye on it, and if it seemed to be catching on, they would follow his company's usual "embrace and extend" strategy. At this point,Gosling lightheartedly interjected "You mean disgrace and distend." Now, the grievance that Gosling was airing was that he felt that this company would take technology from other companies and suborn it for their ownpurposes. But guess what? The shoe is on the other foot here. The Java community did not invent the idea of designing pages as a mixture of static HTML and dynamic code marked with special tags. For example, Cold Fusion did it years earlier. Even ASP (a product from the very software company of theaforementioned manager) popularized this approach before JSP came along and decided to jump on the bandwagon. In fact, JSP not only adopted the general idea, it even used many of the same special tags as ASP did.The JSP is an establishment at the model of Java servlets on of the expression layer technique, it makes the plait write the HTML to become more simple.Be like the SSJS, it also allows you carry the static state HTML contents and servers the script mix to put together the born dynamic state exportation. JSP the script language that the Java is the tacit approval, however, be like the ASP and can use other languages( such as JavaScript and VBScript), the norm of JSP alsoallows to use other languages.1.3JSP CHARACTERISTICSIs a service according to the script language in some one language of the statures system this kind of discuss, the JSP should be see make is a kind of script language. However, be a kind of script language, the JSP seemed to be too strong again, almost can use all Javas in the JSP.Be a kind of according to text originally of, take manifestation as the central development technique, the JSP provided all advantages of the Java Servlet, and, when combine with a JavaBeans together, providing a kind of make contents and manifestation that simple way that logic separate. Separate the contents and advantage of logical manifestations is, the personnel who renews the page external appearance need not know the code of Java, and renew the JavaBeans personnel also need not be design the web page of expert in hand, can use to take the page of JavaBeans JSP to define the template of Web, to build up a from have the alike external appearance of the website that page constitute. JavaBeans completes the data to provide, having no code of Java in the template thus, this means that these templates can be written the personnel by a HTML plait to support. Certainly, can also make use of the Java Servlet to control the logic of the website, adjust through the Java Servlet to use the way of the document of JSP to separate website of logic and contents.Generally speaking, in actual engine of JSP, the page of JSP is the edit and translate type while carry out, not explain the type of. Explain the dynamic state web page development tool of the type, such as ASP, PHP3 etc., because speed etc. reason, have already can't satisfy current the large electronic commerce needs appliedly, traditional development techniques are all at to edit and translate the executive way change, such as the ASP → ASP+;PHP3 → PHP4.In the JSP norm book, did not request the procedure in the JSP code part( be called the Scriptlet) and must write with the Java definitely. Actually, have some engines of JSP are adoptive other script languages such as the EMAC- Script, etc., but actually this a few script languages also are to set up on the Java, edit and translate for the Servlet to carry out of. Write according to the norm of JSP, have no Scriptlet of relation with Java also is can of, however, mainly lie in the ability and JavaBeans, the Enterprise JavaBeanses because of the JSP strong function to work together, so even is the Scriptlet part not to use the Java, edit and translate of performance code also should is related with Java.1.4JSP MECHANISMTo comprehend the JSP how unite the technical advantage that above various speak of, come to carry out various result easily, the customer must understand the differentiation of" the module develops for the web page of the center" and"the page develops for the web page of the center" first.The SSJS and ASP are all in several year ago to release, the network of that time is still very young, no one knows to still have in addition to making all business, datas and the expression logic enter the original web page entirely heap what better solve the method. This kind of model that take page as the center studies and gets the very fast development easily. However, along with change of time, the people know that this kind of method is unwell in set up large, the Web that can upgrade applies the procedure. The expression logic write in the script environment was lock in the page, only passing to shear to slice and glue to stick then can drive heavy use. Express the logic to usually mix together with business and the data logics, when this makes be the procedure member to try to change an external appearance that applies the procedure but do not want to break with its llied business logic, apply the procedure of maintenance be like to walk the similar difficulty on the eggshell. In fact in the business enterprise, heavy use the application of the module already through very mature, no one would like to rewrite those logics for their applied procedure.HTML and sketch the designer handed over to the implement work of their design the Web plait the one who write, make they have to double work- Usually is the handicraft plait to write, because have no fit tool and can carry the script and the HTML contents knot to the server to put together. Chien but speech, apply the complexity of the procedure along with the Web to promote continuously, the development method that take page as the center limits sex to become to get up obviously.At the same time, the people always at look for the better method of build up the Web application procedure, the module spreads in customer's machine/ server the realm. JavaBeans and ActiveX were published the company to expand to apply the procedure developer for Java and Windows to use to come to develop the complicated procedure quickly by" the fast application procedure development"( RAD) tool. These techniques make the expert in the some realm be able to write the module for the perpendicular application plait in the skill area, but the developer can go fetch the usage directly but need not control the expertise of this realm.Be a kind of take module as the central development terrace, the JSP appeared. It with the JavaBeans and Enterprise JavaBeans( EJB) module includes the model of the business and the data logic for foundation, provide a great deal of label and a script terraces to use to come to show in the HTML page from the contents of JavaBeans creation or send a present in return. Because of the property that regards the module as the center of the JSP, it can drive Java and not the developer of Java uses equally. Not the developer of Java can pass the JSP label( Tags) to use the JavaBeans that the deluxe developer of Java establish. The developer of Java not only can establish and use the JavaBeans, but also can use the language of Java to come to control more accurately in the JSP page according to the expression logic of the first floor JavaBeans.See now how JSP is handle claim of HTTP. In basic claim model, a claim directly was send to JSP page in. The code of JSP controls to carry on hour of the logic processing and module of JavaBeanses' hand over with each other, and the manifestation result in dynamic state bornly, mixing with the HTML page of the static state HTML code. The Beans can be JavaBeans or module of EJBs.Moreover, the more complicated claim model can see make from is request other JSP pages of the page call sign or Java Servlets.The engine of JSP wants to chase the code of Java that the label of JSP, code of Java in the JSP page even all converts into the big piece together with the static state HTML contents actually. These codes piece was organized the Java Servlet that customer can not see to go to by the engine of JSP, then the Servlet edits and translate them automatically byte code of Java.Thus, the visitant that is the website requests a JSP page, under the condition of it is not knowing, an already born, the Servlet actual full general that prepared to edit and translate completes all works, very concealment but again andefficiently. The Servlet is to edit and translate of, so the code of JSP in the web page does not need when the every time requests that page is explain. The engine of JSP need to be edit and translate after Servlet the code end is modify only once, then this Servlet that editted and translate can be carry out. The in view of the fact JSP engine auto is born to edit and translate the Servlet also, need not procedure member begins to edit and translate the code, so the JSP can bring vivid sex that function and fast developments need that you are efficiently. Compared with the traditional CGI, the JSP has the equal advantage. First, on the speed, the traditional procedure of CGI needs to use the standard importation of the system to output the equipments to carry out the dynamic state web page born, but the JSP is direct is mutually the connection with server. And say for the CGI, each interview needs to add to add a progress to handle, the progress build up and destroy by burning constantly and will be a not small burden for calculator of be the server of Web. The next in order, the JSP is specialized to develop but design for the Web of, its purpose is for building up according to the Web applied procedure, included the norm and the tool of a the whole set. Use the technique of JSP can combine a lot of JSP pages to become a Webapplication procedure very expediently.JSP的技术发展历史作者:Kathy Sierra and Bert Bates来源:Servlet&JSPJava Server Pages(JSP)是一种基于web的脚本编程技术,类似于网景公司的服务器端Java脚本语言——server-side JavaScript(SSJS)和微软的Active Server Pages(ASP)。

(完整word版)JAVA外文文献+翻译

(完整word版)JAVA外文文献+翻译

燕山大学本科生毕业设计(翻译)1 Java and the InternetIf Java is, in fact, yet another computer programming language, you may question why it is so important and why it is being promoted as a revolutionarystep in computer programming. The answer isn ’t immediately obvious if you coming from a traditional programming perspective. Although Java is very useful for solving traditional stand-alone programming problems, it is also important because it will solve programming problems on the World Wide Web.1.Client-side programmingThe Web ’s in itial server-browser design provided for interactive content, but the interactivity was completely provided by the server. The server produced static pages for the client browser, which would simply interpret and display them. Basic HTML contains simple mechanisms f or data gathering: text-entry boxes, check boxes, radio boxes, lists and drop-down lists, as well as a button that can only be programmed to reset the data on the form or“submit ”on the form back to the server. This submission passes t hrough the Common Gateway Interface (CGI) provided on all Web servers. The text within the submission tells CGI what to do with it. The most common action is to run a program located on the server in a directory that ’s typically called “-bin.” (If you watch the address w indow at the top of your browser when you push a button on a Web page, you can sometimes see “cgi -bin ” within all the gobbledygook there.) These programs can be written in most languages. Perl is a common choice because it is designed for text manipulation and is interpreted, so it can be installed on any server regardless of processor or operating system. Many powerful Web sites today are built strictly on CGI, and you can in fact do nearly anything with it. However, Web sites built on CGI programs can rapidly become overly complicated to maintain, and there is also the problem of response time. The response of a CGI program depends on how much data must。

Java技术外文翻译文献

Java技术外文翻译文献

Java技术外文翻译文献(文档含中英文对照即英文原文和中文翻译)外文:Core Java™ Volume II–Advanced Features When Java technology first appeared on the scene, the excitement was not about a well-crafted programming language but about the possibility of safely executing applets that are delivered over the Internet (see V olume I, Chapter 10 for more information about applets). Obviously, delivering executable applets is practical only when the recipients are sure that the code can't wreak havoc on their machines. For this reason, security was and is a major concern of both the designers and the users of Java technology. This means that unlike other languages andsystems, where security was implemented as an afterthought or a reaction to break-ins, security mechanisms are an integral part of Java technology.Three mechanisms help ensure safety:•Language design features (bounds checking on arrays, no unchecked type conversions, no pointer arithmetic, and so on).•An access control mechanism that controls what the code can do (such as file access, network access, and so on).•Code signing, whereby code authors can use standard cryptographic algorithms to authenticate Java code. Then, the users of the code can determine exactly who created the code and whether the code has been altered after it was signed.Below, you'll see the cryptographic algorithms supplied in the java.security package, which allow for code signing and user authentication.As we said earlier, applets were what started the craze over the Java platform. In practice, people discovered that although they could write animated applets like the famous "nervous text" applet, applets could not do a whole lot of useful stuff in the JDK 1.0 security model. For example, because applets under JDK 1.0 were so closely supervised, they couldn't do much good on a corporate intranet, even though relatively little risk attaches to executing an applet from your company's secure intranet. It quickly became clear to Sun that for applets to become truly useful, it was important for users to be able to assign different levels of security, depending on where the applet originated. If an applet comes from a trusted supplier and it has not been tampered with, the user of that applet can then decide whether to give the applet more privileges.To give more trust to an applet, we need to know two things:•Where did the applet come from?•Was the code corrupted in transit?In the past 50 years, mathematicians and computer scientists have developed sophisticated algorithms for ensuring the integrity of data and for electronic signatures. The java.security package contains implementations of many of these algorithms. Fortunately, you don't need to understand the underlying mathematics to use the algorithms in the java.security package. In the next sections, we show you how message digests can detect changes in data files and how digital signatures can prove the identity of the signer.A message digest is a digital fingerprint of a block of data. For example, the so-called SHA1 (secure hash algorithm #1) condenses any data block, no matter how long, into a sequence of 160 bits (20 bytes). As with real fingerprints, one hopes that no two messages have the same SHA1 fingerprint. Of course, that cannot be true—there are only 2160 SHA1 fingerprints, so there must be some messages with the same fingerprint. But 2160is so large that the probability of duplication occurring is negligible. How negligible? According to James Walsh in True Odds: How Risks Affect Your Everyday Life (Merritt Publishing 1996), the chance that you will die from being struck by lightning is about one in 30,000. Now, think of nine other people, for example, your nine least favorite managers or professors. The chance that you and all of them will die from lightning strikes is higher than that of a forged message having the same SHA1 fingerprint as the original. (Of course, more than ten people, none of whom you are likely to know, will die from lightning strikes. However, we are talking about the far slimmer chance that your particular choice of people will be wiped out.)A message digest has two essential properties:•If one bit or several bits of the data are changed, then the message digest also changes.• A forger who is in possession of a given message cannot construct a fake message that has the same message digest as the original.The second property is again a matter of probabilities, of course. Consider the following message by the billionaire father:"Upon my death, my property shall be divided equally among my children; however, my son George shall receive nothing."That message has an SHA1 fingerprint of2D 8B 35 F3 BF 49 CD B1 94 04 E0 66 21 2B 5E 57 70 49 E1 7EThe distrustful father has deposited the message with one attorney and the fingerprint with another. Now, suppose George can bribe the lawyer holding the message. He wants to change the message so that Bill gets nothing. Of course, that changes the fingerprint to a completely different bit pattern:2A 33 0B 4B B3 FE CC 1C 9D 5C 01 A7 09 51 0B 49 AC 8F 98 92Can George find some other wording that matches the fingerprint? If he had been the proud owner of a billion computers from the time the Earth was formed, each computing a million messages a second, he would not yet have found a message he could substitute.A number of algorithms have been designed to compute these message digests. The two best-known are SHA1, the secure hash algorithm developed by the National Institute of Standards and Technology, and MD5, an algorithm invented by Ronald Rivest of MIT. Both algorithms scramble the bits of a message in ingenious ways. For details about these algorithms, see, for example, Cryptography and Network Security, 4th ed., by William Stallings (Prentice Hall 2005). Note that recently, subtle regularities have been discovered in both algorithms. At this point, most cryptographers recommend avoiding MD5 and using SHA1 until a stronger alternative becomes available.The Java programming language implements both SHA1 and MD5. The MessageDigest class is a factory for creating objects that encapsulate the fingerprinting algorithms. It has a static method, called getInstance, that returns an object of a class that extends the MessageDigest class. This means the MessageDigest class serves double duty:•As a factory class•As the superclass for all message digest algorithmsFor example, here is how you obtain an object that can compute SHA fingerprints:MessageDigest alg = MessageDigest.getInstance("SHA-1");(To get an object that can compute MD5, use the string "MD5" as the argument to getInstance.)After you have obtained a MessageDigest object, you feed it all the bytes in the message by repeatedly calling the update method. For example, the following code passes all bytes in a file to the alg object just created to do the fingerprinting:InputStream in = . . .int ch;while ((ch = in.read()) != -1)alg.update((byte) ch);Alternatively, if you have the bytes in an array, you can update the entire array at once:byte[] bytes = . . .;alg.update(bytes);When you are done, call the digest method. This method pads the input—as required by the fingerprinting algorithm—does the computation, and returns the digest as an array of bytes.byte[] hash = alg.digest();The program in Listing 9-15 computes a message digest, using either SHA or MD5. You can load the data to be digested from a file, or you can type a message in the text area.Message SigningIn the last section, you saw how to compute a message digest, a fingerprint for the original message. If the message is altered, then the fingerprint of the altered message will not match the fingerprint of the original. If the message and its fingerprint are delivered separately, then the recipient can check whether the message has been tampered with. However, if both the message and the fingerprint were intercepted, it is an easy matter to modify the message and then recompute the fingerprint. After all, the message digest algorithms are publicly known, and they don't require secret keys. In that case, the recipient of the forged message and the recomputed fingerprint would never know that the message has been altered. Digital signatures solve this problem.To help you understand how digital signatures work, we explain a few concepts from the field called public key cryptography. Public key cryptography is based on the notion of a public key and private key. The idea is that you tell everyone in the world your public key. However, only you hold the private key, and it is important that you safeguard it and don't release it to anyone else. The keys are matched by mathematical relationships, but the exact nature of these relationships is not important for us.The keys are quite long and complex. For example, here is a matching pair of public and private Digital Signature Algorithm (DSA) keys.Public key:Code View:p:fca682ce8e12caba26efccf7110e526db078b05edecbcd1eb4a208f3ae1617ae01f35b91a47e6df 63413c5e12ed0899bcd132acd50d99151bdc43ee737592e17q: 962eddcc369cba8ebb260ee6b6a126d9346e38c5g:678471b27a9cf44ee91a49c5147db1a9aaf244f05a434d6486931d2d14271b9e35030b71fd7 3da179069b32e2935630e1c2062354d0da20a6c416e50be794ca4y:c0b6e67b4ac098eb1a32c5f8c4c1f0e7e6fb9d832532e27d0bdab9ca2d2a8123ce5a8018b8161 a760480fadd040b927281ddb22cb9bc4df596d7de4d1b977d50Private key:Code View:p:fca682ce8e12caba26efccf7110e526db078b05edecbcd1eb4a208f3ae1617ae01f35b91a47e6df 63413c5e12ed0899bcd132acd50d99151bdc43ee737592e17q: 962eddcc369cba8ebb260ee6b6a126d9346e38c5g:678471b27a9cf44ee91a49c5147db1a9aaf244f05a434d6486931d2d14271b9e35030b71fd73 da179069b32e2935630e1c2062354d0da20a6c416e50be794ca4x: 146c09f881656cc6c51f27ea6c3a91b85ed1d70aIt is believed to be practically impossible to compute one key from the other. That is, even though everyone knows your public key, they can't compute your private key in your lifetime, no matter how many computing resources they have available.It might seem difficult to believe that nobody can compute the private key from the public keys, but nobody has ever found an algorithm to do this for the encryption algorithms that are in common use today. If the keys are sufficiently long, brute force—simply trying all possible keys—would require more computers than can be built from all the atoms in the solar system, crunching away for thousands of years. Of course, it is possible that someone could come up with algorithms for computing keys that are much more clever than brute force. For example, the RSA algorithm (the encryption algorithm invented by Rivest, Shamir, and Adleman) depends on the difficulty of factoring large numbers. For the last 20 years, many of the best mathematicians have tried to come up with good factoring algorithms, but so far with no success. For that reason, most cryptographers believe that keys with a "modulus" of 2,000 bits or more are currently completely safe from any attack. DSA is believed to be similarly secure.Figure 9-12 illustrates how the process works in practice.Suppose Alice wants to send Bob a message, and Bob wants to know this message came from Alice and not an impostor. Alice writes the message and then signs the message digest with her private key. Bob gets a copy of her public key. Bob then applies the public key to verify thesignature. If the verification passes, then Bob can be assured of two facts:•The original message has not been altered.•The message was signed by Alice, the holder of the private key that matches the public key that Bob used for verification.You can see why security for private keys is all-important. If someone steals Alice's private key or if a government can require her to turn it over, then she is in trouble. The thief or a government agent can impersonate her by sending messages, money transfer instructions, and so on, that others will believe came from Alice.The X.509 Certificate FormatTo take advantage of public key cryptography, the public keys must be distributed. One of the most common distribution formats is called X.509. Certificates in the X.509 format are widely used by VeriSign, Microsoft, Netscape, and many other companies, for signing e-mail messages, authenticating program code, and certifying many other kinds of data. The X.509 standard is part of the X.500 series of recommendations for a directory service by the international telephone standards body, the CCITT.The precise structure of X.509 certificates is described in a formal notation, called "abstract syntax notation #1" or ASN.1. Figure 9-13 shows the ASN.1 definition of version 3 of the X.509 format. The exact syntax is not important for us, but, as you can see, ASN.1 gives a precise definition of the structure of a certificate file. The basic encoding rules, or BER, and a variation, called distinguished encoding rules (DER) describe precisely how to save this structure in a binary file. That is, BER and DER describe how to encode integers, character strings, bit strings, and constructs such as SEQUENCE, CHOICE, and OPTIONAL.译文:Java核心技术卷Ⅱ高级特性当Java技术刚刚问世时,令人激动的并不是因为它是一个设计完美的编程语言,而是因为它能够安全地运行通过因特网传播的各种applet。

(完整word版)JAVA外文文献+翻译

(完整word版)JAVA外文文献+翻译

Java and the InternetIf Java is, in fact, yet another computer programming language, you may question why it is so important and why it is being promoted as a revolutionary step in computer programming. The answer isn't immediately obvious if you’re comin g from a traditional programming perspective. Although Java is very useful for solving traditional stand—alone programming problems, it is also important because it will solve programming problems on the World Wide Web。

1.Client—side programmingThe Web’s in itial server—browser design provided for interactive content, but the interactivity was completely provided by the server. The server produced static pages for the client browser, which would simply interpret and display them。

Basic HTML contains simple mechanisms for data gathering: text-entry boxes, check boxes, radio boxes, lists and drop—down lists, as well as a button that can only be programmed to reset the data on the form or “submit” the data on the form back to the server。

Web应用中英文对照外文翻译文献

Web应用中英文对照外文翻译文献

Web应用中英文对照外文翻译文献(文档含英文原文和中文翻译)外文:A Comparative Study of Web Application Design ModelsUsing the Java TechnologiesAbstract.The Servlet technology has been the most widely used technology for building scalable Web applications. In the events, there are four design models for developing Web applications using the Java technologies: Model 1, Model2, Struts, and JavaServer Faces (JSF). Model 1 employs a series of JSP pages; Model 2 adopts the Model-View-Controller pattern; Struts is a framework employing the Model 2 design model; and JSF is a new technology that supports ready-to-use components for rapid Web application development. Model 1 is not recommended for medium-sized and large applications as it introduces maintenance nightmare. This paper compares and evaluates the ease of application development and theperformance of the three design models (Model 2, Struts, and JSF) by building three versions of an online store application using each of the three design models, respectively.1 IntroductionToday, Web applications are the most common applications for presenting dynamic contents. There are a number of technologies for building Web applications, the most popular of which is the Servlet technology . This technology gains its popularity from its superiority over other technologies such as CGI and PHP .Servlets are cumbersome to develop, however, because sending HTML tags requires the programmer to compose them into a String object and send this object to the browser. Also, a minor change to the output requires the servlet to be recompiled. To address this issue, Sun Microsystems invented JavaServer Pages (JSP) . JSP allows HTML tags to be intertwined with Java code and each page is translated into a servlet. A JSP page is a servlet. However, compilation occurs automatically when the page is first requested. As a result, changing the output does not need recompilation. In addition, JSP enables the separation of presentation from the business logic through the use of JavaBeans and custom tag libraries. The norm now in developing Javabased Web applications is to use servlets along with JavaServer Pages.In the later development, there are a number of design models for building servlet/JSP applications: Model 1, Model 2, Struts , and JSF . Model 1 and Model 2 were first mentioned in the early specifications of JSP. Model 1 strictly uses JSP pages, with no servlets, and Model 2 uses the combination of both servlets and JSP pages. The terms of Model 1 and Model 2 have been used ever since. Model 1 is suitable for prototypes and very small applications, and Model 2 is the recommended design model for medium sized and large applications.As Model 2 gained more acceptances in the industry, an open source initiative to build the Struts Framework was initiated. Struts perfects Model 2 by providing the controller part of the Model-View-Controller of Model 2. In addition, Struts provides better page navigation management and several custom tag libraries for more rapid development. Despite its steep learning curve and the fact that it wasnever defined in any specification, Struts has been gaining popularity as the alternative to Model 2.JavaServer Faces is built under the Java Community Process under JSR-127.Sun Microsystems proposed this technology in the hope that JSF will be the ultimate model for building Java Web applications. The most important feature of JSF is the availability of ready-to-use components such as extensible UI components, easy page navigation, input validators, data converters and JavaBeans management.The problem facing servlet/JSP programmers are to choose the most appropriate design model. Clearly, JSF provides a better solution in regard to development time. However, some people are not sanguine to adopt this technology for fear of performance penalty due to the overhead of the JSF implementation.We build three versions of an online store application named BuyDirect using Model 2, Struts and JSF. The parameters compared are the number of lines of code, the number of classes, and the performance measurement results. We investigate which of the design models allows the most rapid development process. We evaluate the performances of the applications built upon these models. We provide some suggestions to perfect the existing design models to make development more rapid.The rest of the paper is organised as follows. Section 2 discusses the issues in Web development. Section 3 explains how the three design models address these development issues. Section 4 provides the details of the hardware and software used in these experiments. Section 5 presents the experiment results and analysis. Section 6 reviews the related work. Section 7 concludes by offering some suggestions to improve the existing design models.2 Java Web Development IssuesAll Java Web development uses the Servlet technology as the underlying technology. As such, all Java Web applications have certain issues that need to be addressed:User Interface. The user interface is what the client browser renders as HTMLtags. Any server-side component used in the application must be encoded into the corresponding HTML elements. Besides for displaying the content and data, the user interface is also responsible in receiving input from the user.●Input Validation. User input needs to be validated. There are two types of inputvalidation, server-side and client-side. As the name implies, the server-side input validation is performed on the server after the input reaches the server.Client-side input validation is done on the browser, usually by using JavaScript or other scripting languages. The advantages of using client-side input validation are prompt response and reducing the server workload. The server-side input validation should always be performed regardless the presence of client-side validation because there is no guarantee the user browser's scripting feature is being on and malicious users can easily work around client-side validation.●Model Objects. Model objects in Java-based Web applications are in the formsof JavaBeans. Model objects make up the Model part of the MVC based design model. A model object can be used to bind a component value to be used at a later stage. In addition, it can encapsulate business logic required for processing.●Page Navigation. Almost all Web applications have multiple pages that the usercan navigate from one to another. All MVC-based design models use a servlet as the Controller part. This servlet also acts as the sole entry point to the application. Which page to be displayed after the current request is determined by the value of a specified request parameter. Managing page navigation is critically important.3 Web Application Design ModelsThe Model 2 design model is based on the Model-View-Controller (MVC) design pattern. As explained by Burbeck , there are three main modules in MVC, the Controller, the View, and the Model. The Controller acts as the central entry point to the application. All user interactions go through this controller. The View contains the presentation part of the application, and the Model stores data or encapsulates business logic of the application. In the later development, the StrutsFramework provides a common framework to easily build Model 2 applications. Then, the last initiative is the JavaServer Faces, which also employs the MVC design pattern.In the following sections, we discuss these three design models and explain how each design model addresses the development issues specified in the previous section.3.1 Model 2A Java Web application that is based on the Model 2 design model has one servlet(called the Controller servlet) that serves as the Controller part. All requests are first handled by this servlet, which immediately dispatches the requests to the appropriate views using RequestDispatcher objects. Views in the Model 2 design model are represented by JSP pages. To store data, a Model 2 application uses JavaBeans, which are the Model part of the application. In addition to storing data, the JavaBeans also encapsulate business logic. Each HTTP request carries an action parameter that indicates which view to dispatch this request to. The programmer must code the HTML tags for user interface in all JSP pages in the application and write input validation code. In addition, the model objects are managed by individual JSP pages.3.2 StrutsThe Struts Framework is an improvement of the Model 2 design model. It provides a default Controller servlet so that the user does not have to write and compile one. Struts alleviates the task of page navigation by allowing navigation rules to be present in its application configuration file (an XML document). Changes to the navigation rules do not require recompilation of a Java servlet class. In addition to easier page navigation, Struts provides custom tag libraries that define tags representing HTML elements. One of these tags is used for error handling and Struts is therefore capable of displaying localized error messages in support for internationalization. Struts applications use JavaBeans as their models, just like the Model 2 design model. In addition, Struts programmers have to write their own input validation code.3.3 JSFJSF also employs a controller servlet that is called FacesServlet. This servlet is the only entry point to a JSF application. JSF also uses JSP pages as its views and JavaBeans as its model objects. Unlike Model 2 and Struts, however, JSF provides ready-to-use user interface components that can be written on JSP pages. Upon an invocation of a page of a JSF application, the FacesServlet constructs a component tree that represents the JSP page being requested. Some of the components can also trigger events, making JSF event-driven. For page navigation, JSF uses an approach similar to Struts, i.e., by allowing navigation rules to be defined in an application configuration file (again, an XML document).What distinguishes a JSF application from non-JSF servlet/JSP application is that JSF applications are event-driven. The user interface of a JSF application is one or many JSP pages that host Web components such as forms and input boxes. These components are represented by JSF custom tags and can hold data. A component can be nested inside another, and it is possible to draw a tree of components. Just as in normal servlet/JSP applications, you use JavaBeans to store the data the user entered.4 Function EnvironmentThe software and hardware details for our experiments are described below.4.1 The Servlet ContainerA Java Web application runs in a servlet container, which is the engine that processes the incoming HTTP requests for the resources in the application. For this research project, we use Tomcat, an open source servlet container from the Apache Software Foundation. The version we use is 6.0.Basically, a servlet container processes a servlet by performing the following tasks:- Creating the HttpRequest Object- Creating the HttpResponse Object- Calling the service method of the Servlet interface, passing the HttpRequest and HttpResponse objects.4.2 Testing ClientsFor performance testing, we emulate multiple users using JMeter 1.9 , also from the Apache Software Foundation. JMeter allows the user to choose the number of threads to perform testing. Each thread emulates a different user. JMeter also lets us choose how many times a test will be done. To test a Web application using JMeter, you direct requests to certain IP address, context path, and port number. You can also specify request parameters to be included in each HTTP request. As the output, JMeter notifies the response time of the server in milliseconds for a test. From the response time, we derive the number of hits/seconds the server is capable of serving.4.3 HardwareWe use different computers for running the applications and for testing, so as to obtain maximum performance measurement accuracy. The computer running the application is a XP machine having the following hardware specifications: Intel Core 1GHz CPU with 1G RAM. The computer running the testing clients is a Windows 2000 machine running JMeter. The computer has the following specifications: Intel Core 1GHz CPU with 1G RAM.5 ResultsWe obtain experimental results in two categories: the ease of development and performance. The ease of development category compares the number of classes and the number of lines of code. These numbers indicate how easy it is to develop an application by following a certain design model. An application with the fewer number of classes or the number of lines of code indicates that the application is relatively easier to build. The application with the more number of classes indicates that the application takes more time to develop.The performance measurement results are obtained by comparing two operations. The Search operation is the most common operation in such an application,and the Browse operation.5.1 Ease of Application DevelopmentAs Table 1 shows, it takes the most effort to implement the Model 2 design model. Using Struts alleviates the problem a bit, and the best saving in the development comes if one uses JSF.Table 1. The number of classes and the number of lines for the applications under studyThe Model 2 design model is characterised by the presence of a Controller servlet and a number of JavaBeans classes (as the Model) and JSP pages (as the Views). The Controller servlet is responsible for page navigation rules that employ a series of if statements. Model 2 application programmers must also code for the input validation that in this research is implemented inside a number of custom tag libraries. The other classes in the Model 2 design model are custom tag library and the tag library descriptors responsible for input validation and data display. In fact, input validation takes 590 lines of code, or almost 30% of the total amount of code.In the Struts application, the Controller servlet is provided by the framework, therefore a Struts programmer saves time for not having to write one. However, he/she still needs to write page navigation rules in the Application Configuration file, which is easier than writing a servlet because the Application Configuration file can be edited using a text editor and no compilation is necessary. Input validation must still be done manually, even though the Struts Framework provides an error handling mechanism. The number of classes and the number of lines of code for input validation are almost similar to the Model 2 application. In Struts, the other classes are Action classes to which the default Controller servlet dispatches requests.In JSF input validation comes free through the availability of validatorcomponent. As a result, a JSF application developer can skip this task. In addition, page navigation takes the same course as Struts, i.e. by utilising an Application Configuration file. The other classes in JSF are a ContextListener, an ActionListener, and a Database utility class.5.2 Performance MeasurementFor each operation, we measure the server response time (in milliseconds) for 1 to 10 concurrent users. The number of users is specified by setting the number of threads in Jmeter. Each test is conducted 10 times and the average is taken. Each operation is discussed further is the following sub-sections.5.2.1 Search OperationThe Search operation whose name or description matches the keyword. There is one SQL SELECT statement performed. Figure 2 compares the three versions of applications for the Search operation.Fig. 2. The performance comparison for the Search operation For the Model 2 application, the average server response time for one user is 173 ms and for 10 users is 919 ms. For the Struts application, these numbers are 189 ms and 900 ms, respectively. For the application built using JSF, the average server response time is 210 ms for one user and 932 ms for 10 users. The increase of the response time is proportional to the increase of the number of concurrent users, which means that the server is still able to cope with the load.The Model 2 application has the least overhead, therefore the averageperformance should be better than the Struts and JSF applications. However, the Struts application performs as well as the Model 2 application. This is because the server has enough memory to load all Struts libraries required to run Struts. Also, note that page navigation rules in Struts are loaded and stored in an object called ActionMapping. Therefore, given an action request parameter, the next page of navigation is obtained through a look-up. On the other hand, the Model 2 application uses a series of if statements to find the next page of navigation, given the action request parameter.The JSF application performs slightly worse than the other applications in almost all numbers of concurrent users. This could be due to the time taken by the JSF implementation to construct a component tree for each page requested. However, the difference in server response time between JSF and other applications is not that significant.5.2.2 Browse OperationThe Browse operation,like the Search operation, there is one SQL SELECT statement performed. Figure 3 gives the test results for this operation.Fig. 3. The performance comparison for the Browse operation On average, the Model 2 application performs the best because it has the least overhead. The average server response time is 111 ms for one user and 899 ms for 10 users. The Struts application has comparable performance, with one user average server response time of 180 ms and 10 user response time of 920 ms. The JSF lacks a bit behind the two applications with these numbers being 190 and 1009ms respectively. The increase of the server response time is proportional to the increase of the number of concurrent users, which means the server is able to serve those users well. The average performance measurement results of the Browse operation are very similar to the ones for the Search operation because the database operations of both operations are also similar.6 Related WorkCompare the performance of database-based Web applications using Java servlets, PHP version 3, and Common Gateway Interface (CGI). After a series of benchmark tests that performs data retrieval from a MySQL database, find that the solution of Java servlets with persistent database connection has the best performance. PHP3 using persistent database connections performs fairly well when compared to the CGI solution,also mention the advantages of using Java servlets. According to these authors. Java servlets are an excellent choice to meet the requirement of e-commerce (such as online shopping) applications and are able to handle client requests in a highly interactive mode.Comparing PHP 4, Java servlets, and Enterprise JavaBeans. Measure the performance of these three architectures using two applications. Study reveals that PHP4 is more efficient than Java servlets, and the EJBs perform even worse than servlets. However, note that servlets, being part of the Java solution, provides the flexibility of being able to be ported to another system with a different operating system.7 ConclusionWe find that it is most rapid to build Web applications using JSF. Model 2 applications are the least rapid but give the best performance. Struts applications sit in the middle of the other two design models in both comparisons.We make some suggestions that could improve the Servlets technology in general and enhance the performance of applications based on both design models. Struts. Struts is not based on any specification and there is no documentation that discusses its internal working. Therefore, it is hard to know what have been implemented and what could be improved.●The Servlets Technology. The Servlet 2.3 Specification does not define anycaching mechanism. There is no mention of caching in the upcoming Servlet2.4 Specification either. Despite the dynamic nature of the content of a Webapplication, some contents do not change very often. For example, the categories of products that a user can browse in an online store application probably only change once in a month. If those semi-static contents must be generated from the database every time they are requested, a lot of programming resources will be wasted. Servlet programmers get around the absence of caching by writing an object that caches certain content. However, since there is no standard for caching, many programmers write the same piece of code again and again.●Model 2.The main drawback is that the page navigation rules are hard-coded inthe Controller servlet. This means any minor change to the program flow will require the Controller servlet to be re-compiled. The solution to this problem is to provide a mapper that reads the page navigation rules when the application starts. The code could be conveniently written in the init method of the Controller servlet. This method is only executed once, i.e. the first time the servlet is loaded into memory. If the properties file needs to be re-read every time it changes, the programmer can check the timestamp of the properties file for each request, and compares it with the previous read of this file. If the timestamp is more current than the previous read, the mapper can be re-constructed. This feature can be enabled and disabled by using an initial parameter in the Context object. At the development phase, this feature should be enabled. At deployment, this feature should be off. The use of the properties file to store the page navigation rules also makes it possible to avoid a series of if statements in the Controller Servlet, which can be time-consuming for every request. Instead, a HashMap can be used, with action request parameters as keys and the next JSP pages as values. The other disadvantage of this design model is the absence of standard components for input validation and user interface. However, this has been solved in JSF.●JSF. JSF provides solutions to common problems in Web development, such aspage navigation management, UI components and input validators. However, because this technology is still very young, there are not too many UIcomponents available, forcing programmers to combine JSF with non-JSF servlets/JSP pages. JSF is event-driven. JSF programmers determine the behavior of a JSF application by writing event listeners, just like those listeners in a Swing application. In JSF version 1.0, there are currently two types of events that can be triggered: ActionEvent and ValueChangedEvent. However, this is good enough to provide sufficient level of interactivity between the application and its users. Adding more types of events will definitely make JSF more appealing.References[1].Cecchet, E., Chanda A., Elnikety S., Marguerite J., Zwaenepoel W.: Performance Comparison of Middleware Architectures for Generating Dynamic Web Content. Proceeding of the 4th International Middelware Conference, 2003.[2].Cecchet, E., Marguerite, J., and Zwaenepoel, W.: Performance and Scalability of EJB Applications. Proceedings of OOPSLA’02, 2002.[3].Wu, A., Wang, H., and Wilkins, D.: Performance Comparison of Alternative Solutions for Web-To-Database Applications. Proceedings of the Southern Conference on Computing, the University of Southern Mississippi, 2000.基于Java技术的Web应用设计模型的比较研究摘要Servlet技术在建立可扩展性Web应用中是被应用最广泛的技术。

JavaWeb前台设计与实现外文翻译

JavaWeb前台设计与实现外文翻译
Both the strategic needs or operational information needs of each database development projects normally concentrated in a database. Some projects only concentrated in the database definition, design and implementation of a database, as a follow-up to the basis of the development of information systems. However, in most cases, the database and associated information processing function as a complete information systems development project was part of the development.
one.System Development Life Cycle
Guide management information system development projects is the traditional process of system development life cycle (SDLC). System development life cycle is an organization of the database designers and programmers information system composed of the Panel of Experts detailed description, development, maintenance and replacement of the entire information system steps. This process is because Waterfall than for every step into the adjacent the next step, that is, the information system is a specification developed by a piece of land, every piece of the output is under an input. However shown in the figure, these steps are not purely linear, each of the steps overlap in time (and thus can manageparallel steps), but when the need to reconsider previous decisions, but also to roll back some steps ahead. (And therefore water can be put back in the waterfall!)

java毕业设计外文文献原文及译文

java毕业设计外文文献原文及译文

英文文献及中文翻译Thinking in JavaAlthough it is based on C++, Java is more of a “pure” object-oriented language.Both C++ and Java are hybrid languages, but in Java the designers felt that the hybridization was not as important as it was in C++. A hybrid language allows multiple programming styles; the reason C++ is hybrid is to support backward compatibility with the C language. Because C++ is a superset of the C language, it includes many of that language’s undesirable features, which can make some aspects of C++ overly complicated. The Java language assumes that you want to do only object-oriented programming. This means that before you can begin you must shift your mindset into an object-oriented world (unless it’s already there). The benefit of this initial effort is the ability to program in a language that is simpler to learn and to use than many other OOP languages. In this chapter we’ll see the basic components of a Java program and we’ll learn that everything in Java is an object, even a Java program.Each programming language has its own means of manipulating data. Sometimes the programmer must be constantly aware of what type of manipulation is going on. Are you manipulating the object directly, or are you dealing with some kind of indirect representation (a pointer in C or C++) that must be treated with a special syntax?All this is simplified in Java. You treat everything as an object, using a single consistent syntax. Although you treat everything as an object, the identifier you manipulate is actually a “reference” to an object. You might imagine this scene as a television (the object) with your remote control (the reference). As long as you’re holding this reference, you have a connection to the television, but when someone says “change the channel” or “lower the volume,” what you’re manipulating is the reference, which in turn modifies the object. If you want to move around the room and still control the television, you take the remote/reference with you, not the television.Also, the remote control can stand on its own, with no television. That is, just because you have a reference doesn’t mean there’s necessarily an object connected to it. So if you want to hold a word or sentence, you create a String reference:But here you’ve created only the reference, not an object. If you decided to send a message to s at this point, you’ll get an error (at run time) because s isn’t actually attached to anything (there’s no television). A safer practice, then, is always to initialize a reference when you create it.However, this uses a special Java feature: strings can be initialized with quoted text. Normally, you must use a more general type of initialization for objectsWhen you create a reference, you want to connect it with a new object. You do so, in general, with the new keyword. The keyword new says, “Make me a new one of these objects.” So in the preceding example, you can say:Not only does this mean “Make me a new String,” but it also gives information about how to make the String by supplying an initial character string.Of course, String is not the only type that exists. Java comes with a plethora of ready-made types. What’s more important is that you can create your own types. In fact, that’s the fundamental activity in Java programming, and it’s what you’ll be learning about in the rest of this bookIt’s useful to visualize some aspects of how things are laid out while the program is running—in particular how memory is arranged. There are six different places to store data: Registers. This is the fastest storage because it exists in a place different from that of other storage: inside the processor. However, the number of registers is severely limited, so registers are allocated by the compiler according to its needs. You don’t have direct contr ol, nor do you see any evidence in your programs that registers even exist.The stack. This lives in the general random-access memory (RAM) area, but has direct support from the processor via its stack pointer. The stack pointer is moved down to create new memory and moved up to release that memory. This is an extremely fast and efficient way to allocate storage, second only to registers. The Java compiler must know, while it is creating the program, the exact size and lifetime of all the data that is stored on the stack, because it must generate the code to move the stack pointer up and down. This constraint places limits on the flexibility of your programs, so while some Java storage exists on the stack—in particular, object references—Java objects themselves are not placed on the stack. The heap. This is a general-purpose pool of memory (also in the RAM area) where all Java objects live. The nice thing about the heap is that, unlike the stack, the compiler doesn’t needto know how much storage it needs to allocate from the heap or how long that storage must stay on the heap. Thus, there’s a great deal of flexibility in using storage on the heap. Whenever you need to create an object, you simply write the code to create it by using new, and the storage is allocated on the heap when that code is executed. Of course there’s a price you pay for this flexibility. It takes more time to allocate heap storage than it does to allocate stack storage (if you even could create objects on the stack in Java, as you can in C++). Static storage. “Static” is used here in the sense of “in a fixed location” (although it’s also in RAM). Static storage contains data that is available for the entire time a program is running. You can use the static keyword to specify that a particular element of an object is static, but Java objects themselves are never placed in static storage.Constant storage. Constant values are often placed directly in the program code, which is safe since they can never change. Sometimes constants are cordoned off by themselves so that they can be optionally placed in read-only memory (ROM), in embedded systems.Non-RAM storage. If data lives completely outside a program, it can exist while the program is not running, outside the control of the program. The two primary examples of this are streamed objects, in which objects are turned into streams of bytes, generally to be sent to another machine, and persistent objects, in which the objects are placed on disk so they will hold their state even when the program is terminated. The trick with these types of storage is turning the objects into something that can exist on the other medium, and yet can be resurrected into a regular RAM-based object when necessary. Java provides support for lightweight persistence, and future versions of Java might provide more complete solutions for persistenceOne group of types, which you’ll use quite often in your programming, gets special treatment. You can think of these as “primitive” types. The reason for the special trea tment is that to create an object with new—especially a small, simple variable—isn’t very efficient, because new places objects on the heap. For these types Java falls back on the approach taken by C and C++. That is, instead of creating the variable by using new, an “automatic” variable is created that is not a reference. The variable holds the value, and it’s placed on the stack, so it’s much more efficient.Java determines the size of each primitive type. These sizes don’t change from one machine architecture to another as they do in most languages. This size invariance is one reason Java programs are portableJava编程思想“尽管以C++为基础,但Java是一种更纯粹的面向对象程序设计语言”。

Java编程语言外文翻译、英汉互译、中英对照

Java编程语言外文翻译、英汉互译、中英对照

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外文翻译原文及译文学院计算机学院专业计算机科学与技术班级学号姓名指导教师负责教师Java(programming language)Java is a general-purpose, concurrent, class-based, object-oriented computer program- -ming language that is specifically designed to have as few implementation dependencies as possible. It is intended to let application developers "write once, run anywhere" (WORA), meaning that code that runs on one platform does not need to be recompiled to run on another. Java applications are typically compiled to byte code (class file) that can run on any Java virtual machine(JVM) regardless of computer architecture. Java is, as of 2012, one of the most popular programming languages in use, particularly for client-server web applications, with a reported 10 million users. Java was originally developed by James Gosling at Sun Microsystems (which has since merged into Oracle Corporation) and released in 1995 as a core component of Sun Microsystems' Java platform. The language derives much of its syntax from C and C++, but it has fewer low-level facilities than either of them.The original and reference implementation Java compilers, virtual machines, and class libraries were developed by Sun from 1991 and first released in 1995. As of May 2007, in compliance with the specifications of the Java Community Process, Sun relicensed most of its Java technologies under the GNU General Public License. Others have also developed alternative implementations of these Sun technologies, such as the GNU Compiler for Java and GNU Classpath.Java is a set of several computer software products and specifications from Sun Microsystems (which has since merged with Oracle Corporation), that together provide a system for developing application software and deploying it in across-platform computing environment. Java is used in a wide variety of computing platforms from embedded devices and mobile phones on the low end, to enterprise servers and supercomputers on the high end. While less common, Java appletsare sometimes used to provide improved and secure functions while browsing the World Wide Web on desktop computers.Writing in the Java programming language is the primary way to produce code that will be deployed as Java bytecode. There are, however, byte code compilers available forother languages such as Ada, JavaScript, Python, and Ruby. Several new languages have been designed to run natively on the Java Virtual Machine (JVM), such as Scala, Clojure and Groovy.Java syntax borrows heavily from C and C++, but object-oriented features are modeled after Smalltalk and Objective-C. Java eliminates certain low-level constructs such as pointers and has a very simple memory model where every object is allocated on the heap and all variables of object types are references. Memory management is handled through integrated automatic garbage collection performed by the JVM.An edition of the Java platform is the name for a bundle of related programs from Sun that allow for developing and running programs written in the Java programming language. The platform is not specific to any one processor or operating system, but rather an execution engine (called a virtual machine) and a compiler with a set of libraries that are implemented for various hardware and operating systems so that Java programs can run identically on all of them. The Java platform consists of several programs, each of which provides a portion of its overall capabilities. For example, the Java compiler, which converts Java source code into Java byte code (an intermediate language for the JVM), is provided as part of the Java Development Kit (JDK). The Java Runtime Environment(JRE), complementing the JVM with a just-in-time (JIT) compiler, converts intermediate byte code into native machine code on the fly. An extensive set of libraries are also part of the Java platform.The essential components in the platform are the Java language compiler, the libraries, and the runtime environment in which Java intermediate byte code "executes" according to the rules laid out in the virtual machine specification.In most modern operating systems (OSs), a large body of reusable code is provided to simplify the programmer's job. This code is typically provided as a set of dynamically loadable libraries that applications can call at runtime. Because the Java platform is not dependent on any specific operating system, applications cannot rely on any of the pre-existing OS libraries. Instead, the Java platform provides a comprehensive set of its own standard class libraries containing much of the same reusable functions commonly found in modern operating systems. Most of the system library is also written in Java. For instance, Swing library paints the user interface and handles the events itself, eliminatingmany subtle differences between how different platforms handle even similar components.The Java class libraries serve three purposes within the Java platform. First, like other standard code libraries, the Java libraries provide the programmer a well-known set of functions to perform common tasks, such as maintaining lists of items or performing complex string parsing. Second, the class libraries provide an abstract interface to tasks that would normally depend heavily on the hardware and operating system. Tasks such as network access and file access are often heavily intertwined with the distinctive implementations of each platform. The and java.io libraries implement an abstraction layer in native OS code, then provide a standard interface for the Java applications to perform those tasks. Finally, when some underlying platform does not support all of the features a Java application expects, the class libraries work to gracefully handle the absent components, either by emulation to provide a substitute, or at least by providing a consistent way to check for the presence of a specific feature.The success of Java and its write once, run anywhere concept has led to other similar efforts, notably the .NET Framework, appearing since 2002, which incorporates many of the successful aspects of Java. .NET in its complete form (Microsoft's implementation) is currently only fully available on Windows platforms, whereas Java is fully available on many platforms. .NET was built from the ground-up to support multiple programming languages, while the Java platform was initially built to support only the Java language, although many other languages have been made for JVM since..NET includes a Java-like language called Visual J# (formerly named J++) that is incompatible with the Java specification, and the associated class library mostly dates to the old JDK 1.1 version of the language. For these reasons, it is more a transitional language to switch from Java to the .NET platform, than a first class .NET language. Visual J# was discontinued with the release of Microsoft Visual Studio 2008. The existing version shipping with Visual Studio 2005will be supported until 2015 as per the product life-cycle strategy.In June and July 1994, after three days of brainstorming with John Gage, the Director of Science for Sun, Gosling, Joy, Naughton, Wayne Rosing, and Eric Schmidt, the team re-targeted the platform for the World Wide Web. They felt that with the advent of graphical web browsers like Mosaic, the Internet was on its way to evolving into the samehighly interactive medium that they had envisioned for cable TV. As a prototype, Naughton wrote a small browser, Web Runner (named after the movie Blade Runner), later renamed Hot Java.That year, the language was renamed Java after a trademark search revealed that Oak was used by Oak Technology. Although Java 1.0a was available for download in 1994, the first public release of Java was 1.0a2 with the Hot Java browser on May 23, 1995, announced by Gage at the Sun World conference. His announcement was accompanied by a surprise announcement by Marc Andreessen, Executive Vice President of Netscape Communications Corporation, that Netscape browsers would be including Java support. On January 9, 1996, the Java Soft group was formed by Sun Microsystems to develop the technology.Java编程语言Java是一种通用的,并发的,基于类的并且是面向对象的计算机编程语言,它是为实现尽可能地减少执行的依赖关系而特别设计的。

Java技术与Web设计外文文献翻译

Java技术与Web设计外文文献翻译

文献信息文献标题:A Comparative Study of Top Web Design Models that are using Java Technologies(使用Java技术的顶级Web设计模型的比较研究)文献作者及出处:Sathyaseelan B, Cordova R S. A Comparative Study of Top Web Design Models that are using Java Technologies[J].International Journal of Innovations and Advancement in Computer Science. 2016,5(5):41-44字数统计:英文1614单词,8806字符;中文2779汉字外文文献A Comparative Study of Top Web Design Models that areusing Java TechnologiesAbstract In today's professional workplace, enterprise applications are complex, adaptable, distributed, part-based, and mission-critical. They might be conveyed as an assortment of platforms across corporate systems, intranets, or the Internet. They are information driven, easy to use, and should meet stringent prerequisites for security, organization, and support. To put it plainly, they are highly complex systems. Various enterprise applications have been in the market today and there are numerous methods available for developing enterprise applications.This paper discusses the major differences between two competing design models for developing Web applications using Java technologies which are Struts and Java Server Faces (JSF). Struts is an open source java framework and is an action-based framework.On the other hand, JSF is a new technology that supports ready-to-use components for rapid Web application development. These two technologies will be analyzed depending on the factors such as the controller flexibility or event handling, navigation, page development, integration and extensibility.Keywords: web design models, Struts, Java Server Faces and Java technologiesI.IntroductionA STRUT is a web application system that has been popular over Java Servlets. It envelops the ordinarily utilized MVC design pattern. A STRUT automates normal tasks, liberating up to explore more of the Action- to-result pages mapping utilizing SML-based configurations. The system makes the progress level subtle elements of the usage of Web-based applications and gives a bit of structural software. JavaServer Faces (JSF) abridges the development of web application user interfaces, usually by defining a user interface component model tied to a well-defined request processing lifecycle. It characterizes a set of UI components— basically, a balanced mapping of the html structure component set along with some extras—that could a be utilized as an application programming interface for extending and modifying standard components or developing new components.II.Key DifferencesThe figures below illustrate the key differences between a STRUTS and JSF request-response scenario. This is necessary in order to fully understand the architecture of each web design models.Figure 1. Struts Request-Response ScenarioIn figure 1, the client sends request to server through a web-browser for aparticular resource. This request is forwarded to the server through a Controller. A servlet goes about as a controller, accepting all requests from the customer. The servlet hands off the request to a different business layer for handling. When processing is finished, the servlet advances or diverts the request to a JSP, which is exclusively in charge of creating the following view for the client. There is no business logic within the JSP.Figure 2. JSF Request-Response ScenarioIn figure 2, the server handles requests from the client, starting from an initial request to a postback request. When a client makes an underlying request for a page, it is asking for the page for the first time. When a client executes a postback, it presents the structure contained on a page that was beforehand stacked into the program as a result of executing an underlying request. When the life cycle handles an underlying request, it just executes the restore view and renders response phases in light of the fact that there is no client information or activities to prepare. Then again, when the life cycle handles a postback, it executes the majority of the phases.III.MethodologyIn this study we will compare JSF and Struts. We will create two modelsemploying the JSF and Struts request-response scenario. JSF is a “component” framework while Struts is an “action” framework.This paper compares and evaluates the ease of application development and the performance of two design models (Struts and JSF) by presenting the two design models and critically analyzes each technology.IV.ChallengesWeb Development ChallengesThe challenges in Web development are much more than the application development. The main challenge is in hosting the application over a webserver and then handling the network issues while accessing those via network. The performances of the web-based application are based on the network availability and its speed. These are not challenges for desktop applications as they run on the local host and the resources are based only on that system.Challenges in STRUTSDespite the fact that Struts accompanies a rundown of remarkable elements however it is important not to neglect the few negative applications about Struts and would require loads of improvements.Greater expectation to learn and adapt - To utilize MVC with STRUTS, you must be alright with the standard JSP, Servlet APIs and a substantial and elaborate system.Poor documentation - Compared to the standard servlet and JSP APIs, STRUTS has less online resources, and some first-time clients locate the online Apache documentation confusing and inadequately sorted out.Less straightforward -With STRUTS applications, there is significantly more going ahead in the background than with ordinary Java-based Web applications which makes it hard to comprehend the system.Challenges in JSFJSF is a very powerful innovation for creating Java-based web applications. It is intended to improve the development of client interfaces for Java Enterprise Edition (Java EE) applications via programmed handling of low level HTTP requests andclient information processing. JSF utilizes a part based model for web advancement. Utilizing the visual JSF web application instrument offered by NetBeans () integrated development environment (IDE), segments can be actually "painted" on a virtual JSF page by relocating them from a palette of JSF segment library.Event handlers can then be characterized for every part the same route concerning creating standalone Java graphical user interface (GUI) application. Route standards are determined for every page from a central XML arrangement document (faces-config.xml). Client activities on a web interface will trigger an event which in return figures out which page is to be shown along the rules specified on that page.This methodology encourages measured and adaptable design, making web application development much more straightforward and faster.The route decides determined for that page. This methodology encourages measured and adaptable configuration, making web application advancement much less difficult and speedier.V.AnalysisIn this study, STRUTS and JSF were analyzed in terms of their controller flexibility or event handling, navigation, page development, integration and extensibility. This is important to compare each web design model and present the advantages and disadvantages of each technology.Controller Flexibility/Event HandlingController is considered as the heart of the Struts. It uses the Front Controller Pattern and Command Pattern. A single servlet takes a request, and then translates HTTP parameters into a Java ActionForm, and passes the ActionForm into a Struts Action class. The URI designates which Action class need to be executed. The Struts framework has one single event handler for the HTTP request. When the request is met by the event handler, the Action returns the result back to the front controller. This in turn will be used to choose the navigation destination.Controller Pattern is been used by the JSF. Each face request goes through asingle servlet, whose responsibility is to get a faces page with components. It will then trigger the events for each component and render the components using a render toolkit. It is also possible to bound the components to the data from its model. JSF have several event handlers on a page while Struts is geared to one event per request. In addition, with Struts, the ActionForms have to extend Struts classes, creating another layer of complicated coding while JSF gives the ability to peg into the model without breaking layering.NavigationNavigation is a key feature of both Struts and JSF. There are 2 types of navigation: static navigation - when the output of a particular page is known so that it is very easy to predict its expected output; and dynamic navigation – when the output is unpredictable and some business logic determines the output of that particular page. Both frameworks have a declarative navigation model and define navigation using rules inside their XML configuration file. Both JSF and Struts support both types of navigation.Page DevelopmentJSF was built with component models which support RAD development, while struts don’t have that support. The Struts framework provides custom libraries to peg into Action Forms and offers some utilities. JSF provides the ability to build components from a variety of view technologies and does it in such a way to be component based.IntegrationStruts are model neutral, so there is no special hook into a model layer. The page data has to be moved from the Action Form to another Model input format which requires heavy complicated coding. The ActionForm class, provides an extra layer of tedious coding and state transition.JSF, on the other hand, encapsulates and hides the details of any data inside the component tree. Data grids and similar rich components can be bound to any Java class. This allows the combination of JSF and SDO which are powerful RAD development.ExtensibilityBoth Struts and JSF offers the extension of framework to meet expanding requirements. Struts have RequestProcessor class that has various callback methods and is the major grip for struts throughout the life-cycle of a request. JSF also have similar functionality to outspread special life-cycle interfaces. Apart from this, JSF totally decouples the render phase from the controller. This considered as on of the main important feature of JSF that Struts does not incorporate.VI.ConclusionJSF is a much more flexible framework while struts is a sturdy framework and works well. JSF is a strong framework because of its flexible controller and navigation. Furthermore, JSF is built with integration and extensibility. From a strategic direction and programming model, JSF can be a target of new applications.中文译文使用Java技术的顶级Web设计模型的比较研究摘要在当今的专业工作环境中,企业应用程序是复杂的、可适应的、分布式的、基于部件的和任务关键的。

(2021年整理)java介绍外文翻译

(2021年整理)java介绍外文翻译

(完整版)java介绍外文翻译编辑整理:尊敬的读者朋友们:这里是精品文档编辑中心,本文档内容是由我和我的同事精心编辑整理后发布的,发布之前我们对文中内容进行仔细校对,但是难免会有疏漏的地方,但是任然希望((完整版)java介绍外文翻译)的内容能够给您的工作和学习带来便利。

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外文原文Introduction to Javaautor:Martin Ngobye.source:Computing Static Slice for Java ProgramsJava is designed to meet the challenges of application development in the context of heterogeneous, network—wide distributed environments. Paramount among these challenges is secure delivery of applications that consume the minimum of system resources, can run on any hardware and software platform, and can be extended dynamically。

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郑州大学西亚斯国际学院毕业论文外文资料翻译学院:电子信息工程学院专业:软件工程(软件开发方向)姓名:xxxx学号: xxxxxxxx附件: 1外文原文 2外文资料翻译指导教师评语:签名:2013年04月25日附件1:外文原文Database Development ProcessBased on information engineering information systems planning database is a source of development projects. These new database development projects is usually in order to meet the strategic needs of organizations, such as improving customer support, improve product and inventory management, or a more accurate sales forecast. H owever, many more database development project is the bottom-up approach emerging, such as information system user needs specific information to complete their work, thus beginning a project request, and as other information systems experts found that organizations need to improve data management and begin new projects. Bottom-up even in the circumstances, to set up an enterprise data model is also necessary to understand the existing database can provide the necessary data, otherwise, the new database, data entities and attributes can be added to the current data resources to the organization.Both the strategic needs or operational information needs of each database development projects normally concentrated in a database. Some projects only concentrated in the database d efinition, design and implementation of a database, a s a follow-up to the basis of the development of information systems. However, in most cases, the database and associated information processing function as a complete information systems development project was part of the development.one. System Development Life CycleGuide management information system development projects is the traditional process of system development life cycle (SDLC). System development life cycle is an organization of the database designers a nd programmers information system composed of the Panel of Experts detailed description, development, maintenance and replacement of the entire information system steps. This process is because Waterfall than for every step into the adjacent the next step, that is, the information system is a specification developed by a piece of land, every piece of the output is under an input. However shown in the figure, these steps are not purely linear, each of the steps overlap in time (and thuscan manage parallel steps), but when the need to reconsider previous decisions, but also to roll back some steps ahead. (And therefore water can be put back in the waterfall!) The system development life cycle including each stage and database development-related activities, therefore, the question of database management systems throughout the entire development process. In Figure 5 we repeat of the system development life cycle stage of the seven, and outlines the common database a t each stage of development activities. Please note that the systems development life cycle stages and database development steps exists between the relationship between the concept of modeling data in both systems development life cycle stages between.1.1 Enterprise ModelingDatabase development process from the enterprise modeling (system development life cycle stage of the project feasibility studies, and to choose a part)Organizations set the scope and general database c ontent. Enterprise modeling in information systems planning and other activities, these activities determine which partof information systems need to change and strengthen the entire organization and outlines the scope of data. In this step, check the current database a nd information systems, development of the project as the main areas of the nature of the business, with a very general description of each term in the development of information systems when needed data. Each item only when it achieved the expected goals of organizations can be when the next step.1.2 Conceptual Data ModelingOne has already begun on the Information System project, the concept of data modeling phase of the information systems needs of all the data. It is divided into two stages. F irst, it began the project in the planning stage. At the same time outlining the establishment of other documents to the existing database without considering the circumstances specific development projects in the scope of the required data. This category only includes high-level data (entities), and main contact. Then in the system development life-cycle analysis stage must have a management i nformation system set the entire organization Details of the data model definition of all data attributes, listing all data types that all data inter-entity business linkages, defining description of the full dataintegrity rules. In the analysis phase, but also the concept of inspection data model (also called the concept behind the model) and the goal of information systems used to explain other aspects of the model of consistency categories, such as processing steps, rules and data processing time of timing. However, even if the concept is such detailed data model is only preliminary, because follow-up information system life cycle activities in the design of services, statements, d isplay and inquiries may find that missing element or mistakes. Therefore, the concept of data often said that modeling is a top-down manner, its areas of operation from the general understanding of the driver, rather than the specific information processing activities by the driver.1.3 Logical Database DesignLogical database design from two perspectives database d evelopment. First, the concept of data model transform into relational database theory based on the criteria that means - between. Then, as the design of information systems, every computer procedures (including procedures for the input and output format), database support services, statements, and inquiries revealed that a detailed examination. In this so-called Bottom-up analysis, accurate verification of the need to maintain the database a nd the data in each affairs, statements and so on the needs of those in the nature of the data. For each separate statements, services, and so on the analysis must take into account a specific, limited but complete database view. When statements, services, and other analysis might be necessary to change the concept of data model. Especially in large-scale projects, the different analytical systems development staff and the team can work independently in different procedures or in a centralized, the details of their work until all the logic design stage may be displayed. In these circumstances, logic database design stage must be the original concept of data model and user view these independent or merged into a comprehensive design. In logic design information systems also identify additional information processing needs of these new demands at this time must be integrated into the logic of earlier identified in the database d esign.Logical database design is based on the final step for the formation of good data specifications and determine the rules, the combination, the data after consultation specifications or converted into basic atomic element. Most of today's database, these rules from therelational database theory and the process known as standardization, #. This step is the result of management of these data have not cited any database management system for a complete description of the database map. Logical database design completed, we began to identify in detail the logic of the computer program and maintenance, the report contents of the database for inquiries.1.4 Physical database design and definitionPhysical database design and definition phase decisions computer memory (usually disk) database i n the organization, definition of According to the library management system for physical structure, the procedures o utlined processing services, produce the desired management information and decision support statements. The objective of this stage is to design an effective and safe management of all data-processing database, the physical database design to c losely integrate the information systems of other physical aspects of the design, including procedures, computer hardware, operating systems and data communications networks.1.5 Database ImplementationThe database prepared by the realization stage, testing and installation procedures for handling databases. D esigners can use the standard programming language (such as COBOL, C or Visual Basic), the dedicated database processing languages (such as SQL), or the process of the non-exclusive language programming in order to produce a statement of the fixed format, the result will be displayed, and may also include charts. In achieving stage, but also the completion of all the database files, training users for information systems (database) user setup program. The final step is to use existing sources of information (documents legacy applications and databases and now needs new data) loading data. Loading data is often the first step in data from existing files and databases t o an intermediate format (such as binary or text files) and then to turn intermediate loading data to a new database. Finally, running databases a nd related applications for the actual user maintenance and retrieval of data. In operation, the regular backup database and the database when damaged or affected resume database.1.6 Database maintenanceDuring the database in the progressive development of database maintenance. In thisstep, in order to meet changing business conditions, in order to correct the erroneous database design, database applications or processing speed increase, delete or change the structure of the database. When a procedure or failure of the computer database affect or damage the database may also be reconstruction. This step usually is the longest in the database development process step, as it continued to databases and related applications throughout the life cycle, the development of each database c an be seen as a brief database d evelopment process and data modeling concepts arise, logical and physical database design and database to achieve dealing with the changes.two. Information System developed by other meansSystem Development Life Cycle minor changes in law or its variant of the often usedto guide information systems and database development. Information System is alife-cycle methodology, it is highly structured approach, which includes many checks and balances to ensure that every step of produce accurate results, and new or alternative information system and it must communications or data definitions consistent existing system needs consistency. System development life cycle because of the regular need to have a working system for a long time been criticized because only work in the systemuntil the end of the whole process generated. More and more organizations now use rapid application development method, it is a includes analysis, design and implementation of steps to repeat the rapid iterative process until convergence to users the system so far. Rapid Application Development Act required the database h as been in existence, and enhance system is mainly to the application of data retrieval application, but not to those who generate and modify database applications.The most widely used method of rapid application development is one of the prototype. The prototype system is a method of iterative development process, analysts and users through close co-operation, continuing to revise the system will eventually convert all the needs of a working system. In this diagram we contains notes, briefly describes each stage of the prototype of the database development activities. Normally, when information systems problems were identified, tried only a rough concept of data modeling. In the development of the initial prototype, the design of the user wants to display and statements, a nd that any new database n eeds and define a term prototypedatabase. This is usually a new database, copy the part of the existing system, but might also added some new content. When the need for new content, these elements are usually from external data sources, such as market research data, the general economic indicators or industry standards. When a prototype of a new version to repeat the achievement and maintenance of database activities. Usually only a minimum level of security and integrity control, because at this time the focus is as soon as possible to produce a prototype version can be used. But document management p roject also deferred to the final, only be used in the delivery of user training. Finally, once constructed an acceptable prototype, developers, and users will be the final decision of whether to prototype delivery and the use of the database. If the system (including database) efficiency is very low, then the system and database will be re-programming andre-organization in order to achieve the desired performance.Along with visual programming tools (such as Visual Basic, Java, Visual C + + and fourth generation language) increasingly popular use of visual programming tools can easily change the user interface with the system, the prototype is becoming the choice of system development methodology. Customers using the prototype method statements and show changes to the content and layout is quite easy. In the process, the new database needs were identified, so it is the development of the use of the existing database should be amended. There is even the possibility of a need for a new database system prototype method, in such circumstances, when the system demand in the iterative process of development in the ever-changing needs access to sample data, the construction or reconstruction of the database prototype.附件1:外文资料翻译数据库开发过程基于信息工程的信息系统规划是数据库开发项目的一个来源。

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