【计算机专业文献翻译】JSP概述
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JSP OverviewJSP is the latest Java technology for web application development and is based on the servlet technology introduced in the previous chapter. While servlets are great in many ways, they are generally reserved for programmers. In this chapter, we look at the problems that JSP technology solves, the anatomy of a JSP page, the relationship between servlets and JSP, and how the server processes a JSP page.In any web application, a program on the server processes requests and generates responses. In a simple one-page application, such as an online bulletin board, you don't need to be overly concerned about the design of this piece of code; all logic can be lumped together in a single program. However, when the application grows into something bigger (spanning multiple pages, using external resources such as databases, with more options and support for more types of clients), it's a different story. The way your site is designed is critical to how well it can be adapted to new requirements and continue to evolve. The good news is that JSP technology can be used as an important part in all kinds of web applications, from the simplest to the most complex.Therefore, this chapter also introduces the primary concepts in the design model recommended for web applications and the different roles played by JSP and other Java technologies in this model.The Problem with ServletsIn many Java servlet-based applications, processing the request and generating the response are both handled by a single servlet class. Example 3-1 shows how a servlet class often looks.Example 3-1. A typical servlet classpublic class OrderServlet extends HttpServlet {public void doGet((HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html");PrintWriter out = response.getWriter( );if (isOrderInfoValid(request)) {saveOrderInfo(request);out.println("<html>");out.println(" <head>");out.println(" <title>Order Confirmation</title>");out.println(" </head>");out.println(" <body>");out.println(" <h1>Order Confirmation</h1>");renderOrderInfo(request);out.println(" </body>");out.println("</html>");}...If you're not a programmer, don't worry about all the details in this code. The point is that the servlet contains request processing and business logic (implemented by methods such as isOrderInfoValid() and saveOrderInfo( )), and also generates the response HTML code, embedded directly in the servlet code using println( ) calls. A more structured servlet application isolates different pieces of the processing in various reusable utility classes and may also use a separate class library for generating the actual HTML elements in the response. Even so, the pure servlet-based approach still has a few problems:Thorough Java programming knowledge is needed to develop and maintain all aspects of the application, since the processing code and the HTML elements are lumped together.Changing the look and feel of the application, or adding support for a new type of client (such as a WML client), requires the servlet code to be updated and recompiled.It's hard to take advantage of web page development tools when designing the application interface. If such tools are used to develop the web page layout, the generated HTML must then be manually embedded into the servlet code, a process which is time consuming, error prone, and extremely boring.Adding JSP to the puzzle lets you solve these problems by separating the request processing and business logic code from the presentation, as illustrated in Figure 3-1. Instead of embedding HTML in the code, place all static HTML in a JSP page, just as in a regular web page, and add a few JSP elements to generate the dynamic parts of the page. The request processing can remain the domain of the servlet, and the business logic can be handled by JavaBeans and EJB components.Figure 3-1. Separation of request processing, business logic, and presentation As I mentioned before, separating the request processing and business logic frompresentation makes it possible to divide the development tasks among people with different skills. Java programmers implement the request processing and business logic pieces, web page authors implement the user interface, and both groups can use best-of-breed development tools for the task at hand. The result is a much more productive development process. It also makes it possible to change different aspects of the application independently, such as changing the business rules without touching the user interface.This model has clear benefits even for a web page author without programming skills, working alone. A page author can develop web applications with many dynamic features, using the JSP standard actions and the JSTL libraries, as well as Java components provided by open source projects and commercial companies.JSP ProcessingJust as a web server needs a servlet container to provide an interface to servlets, the serverneeds a JSP container to process JSP pages. The JSP container is responsible for interceptingrequests for JSP pages. To process all JSP elements in the page, the container first turns the JSP page into a servlet (known as the JSP page implementation class). The conversion is pretty straightforward; all template text is converted to println( ) statements similar to the ones in the handcoded servlet shown in Example 3-1, and all JSP elements are converted to Java code that implements the corresponding dynamic behavior. The container then compiles the servlet class.Converting the JSP page to a servlet and compiling the servlet form the translation phase. The JSP container initiates the translation phase for a page automatically when it receives the first request for the page. Since the translation phase takes a bit of time, the first user to request a JSP page notices a slight delay. The translation phase can also be initiated explicitly; this is referred to as precompilation of a JSP page. Precompiling a JSP page is a way to avoid hitting the first user with this delay. It is discussed in more detail in Chapter 17.The JSP container is also responsible for invoking the JSP page implementation class (the generated servlet) to process each request and generate the response. This is called the request processing phase. The two phases are illustrated in Figure 3-3.Figure 3-2. JSP page translation and processing phasesAs long as the JSP page remains unchanged, any subsequent request goes straight to the request processing phase (i.e., the container simply executes the class file). When the JSP page is modified, it goes through the translation phase again before entering the request processing phase.The JSP container is often implemented as a servlet configured to handle all requests for JSP pages. In fact, these two containers—a servlet container and a JSP container—are often combined in one package under the name web container.So in a way, a JSP page is really just another way to write a servlet without having to be a Java programming wiz. Except for the translation phase, a JSP page is handled exactly like a regular servlet; it's loaded once and called repeatedly, until the server is shut down. By virtue of being an automatically generated servlet, a JSP page inherits all the advantages of a servlet described in Chapter 2: platform and vendor independence, integration, efficiency, scalability, robustness, and security.3.3.1 JSP ElementsThere are three types of JSP elements you can use: directive, action, and scripting. A new construct added in JSP 2.0 is an Expression Language (EL) expression; let's call this a forth element type, even though it's a bit different than the other three.3.3.1.1 Directive elementsThe directive elements, shown in Table 3-1, specify information about the page itself that remains the same between requests—for example, if session tracking is required or not, bufferingTable 3-1. Directive elements3.3.1.2JavaBeans componentsJSP elements, such as action and scripting elements, are often used to work with JavaBeans components. Put succinctly, a JavaBeans component is a Java class that complies with certain coding conventions. JavaBeans components are typically used as containers for information that describes application entities, such as a customer or an order.JSP Application Design with MVCJSP technology can play a part in everything from the simplest web application, such as an online phone list or an employee vacation planner, to complex enterprise applications, such as a human resource application or a sophisticated online shopping site. How large a part JSP plays MVC was first described by Xerox in a number of papers published in the late 1980s. The key differs in each case, of course. In this section, I introduce a design model calledModel-View-Controller (MVC), suitable for logic into three distinct units: the Model, the View, and the Controller. In a server application, we commonly classify the parts of the application as business logic, presentation, and request processing. Business logic is the term used for the manipulation of an application's data, such as customer, product, and order information. Presentation refers to how the application data is displayed to the user, for example, position, font, and size. And finally, request processing is what ties the business logic and presentation parts together. In MVC terms, the Model corresponds to business logic and data, the View to the presentation, and the Controller to the request processing.Why use this design with JSP? The answer lies primarily in the first two elements. Remember that an application data structure and logic (the Model) is typically the most stable part of an application, while the presentation of that data (the View) changes fairly often. Just look at all the face-lifts many web sites go through to keep up with the latest fashion in web design. Yet, the data they present remains the same. Another common example of why presentation should be separated from the business logic is that you may want to present the data in different languages or present different subsets of the data to internal and external users. Access to the data through new types of devices, such as cell phones and personal digital assistants (PDAs), is the latest trend. Each client type requires its own presentation format. It should come as no surprise, then, that separating business logic from the presentation makes it easier to evolve an application as the requirements change; new presentation interfaces can be developed without touching the business logic.This MVC model is used for most of the examples in this book. In Part II, JSP pages are used as both the Controller and the View, and JavaBeans components are used as the Model. The examples in Chapter 5 through Chapter 9 use a single JSP page that handles everything, while Chapter 10 through Chapter 14 show how you can use separate pages for the Controller and the View to make the application easier to maintain. Many types of real-world applications can be developed this way, but what's more important is that this approach allows you to examine all the JSP features without getting distracted by other technologies. In Part III, we look at other possible role assignments when JSP is combined with servlets and Enterprise JavaBeans.JSP 概览JSP是一种用于Web应用程序开发的最新的Java技术,它是建立在servlet 技术基础之上的。
中文翻译JSP技术和ServletsJSP简介JSP(JavaServer Pages)是由Sun Microsystems公司倡导、许多公司参与一起建立的一种动态网页技术标准。
JSP技术有点类似ASP技术,它是在传统的网页HTML文件(*.htm,*.html)中插入Java程序段(Scriptlet)和JSP标记(tag),从而形成JSP文件(*.jsp)。
用JSP开发的Web应用是跨平台的,即能在Linux下运行,也能在其他操作系统上运行。
JSP技术使用Java编程语言编写类XML的tags和scriptlets,来封装产生动态网页的处理逻辑。
网页还能通过tags和scriptlets访问存在于服务端的资源的应用逻辑。
JSP 将网页逻辑与网页设计和显示分离,支持可重用的基于组件的设计,使基于Web的应用程序的开发变得迅速和容易。
Web服务器在遇到访问JSP网页的请求时,首先执行其中的程序段,然后将执行结果连同JSP文件中的HTML代码一起返回给客户。
插入的Java程序段可以操作数据库、重新定向网页等,以实现建立动态网页所需要的功能。
JSP与Java Servlet一样,是在服务器端进行执行的,通常返回该客户端的就是一个HTML文本,因此客户端只要有浏览器就能浏览。
JSP的1.0规范的最后版本是1999年9月推出的,12月又推出了1.1规范。
目前较新的是JSP1.2规范,JSP2.0规范的征求意见稿也已出台。
JSP页面由HTML代码和嵌入其中的Java代码所组成。
JS脚本语言简介JS即javascrip,Javascript是一种由Netscape的LiveScript发展而来的脚本语言,主要目的是为了解决服务器终端语言,比如Perl,遗留的速度问题。
当时服务端需要对数据进行验证,由于网络速度相当缓慢,只有28.8kbps,验证步骤浪费的时间太多。
于是Netscape的浏览器Navigator加入了Javascript,提供了数据验证的基本功能。
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。
(文档含英文原文和中文翻译)中英文对照外文翻译JSP技术Java 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)。
与SSJS和ASP相比,JSP具有更好的可扩展性,并且它不专属于任何一家厂商或某一特定的Web服务器。
尽管JSP规范是由Sun公司制定的,但任何厂商都可以在自己的系统上实现JSP。
在Sun正式发布JSP(Java Server Pages)之后,这种新的Web应用开发技术很快引起了人们的关注。
JSP为创建高度动态的Web应用提供了一个独特的开发环境。
按照Sun的说法,JSP能够适应市场上包括Apache WebServer、IIS4.0在内的85%的服务器产品。
本文将介绍JSP相关的知识,以及JavaBean的相关内容,当然都是比较粗略的介绍其中的基本内容,仅仅起到抛砖引玉的作用,如果读者需要更详细的信息,请参考相应的JSP的书籍。
1.1 概述JSP(Java Server Pages)是由Sun Microsystems公司倡导、许多公司参与一起建立的一种动态网页技术标准,其在动态网页的建设中有其强大而特别的功能。
JSP与Microsoft的ASP技术非常相似。
两者都提供在HTML代码中混合某种程序代码、由语言引擎解释执行程序代码的能力。
下面我们简单的对它进行介绍。
JSP页面最终会转换成servlet。
因而,从根本上,JSP页面能够执行的任何任务都可以用servlet来完成。
然而,这种底层的等同性并不意味着servlet和JSP 页面对于所有的情况都等同适用。
问题不在于技术的能力,而是二者在便利性、生产率和可维护性上的不同。
毕竟,在特定平台上能够用Java编程语言完成的事情,同样可以用汇编语言来完成,但是选择哪种语言依旧十分重要。
附录1 外文参考文献(译文)JSP内置对象有些对象不用声明就可以在JSP页面的Java程序片和表达式部分使用,这就是JSP 的内置对象。
JSP的内置对象有:request、response、session、application、out.response和request对象是JSP内置对象中较重要的两个,这两个对象提供了对服务器和浏览器通信方法的控制。
直接讨论这两个对象前,要先对HTTP协议—Word Wide Wed底层协议做简单介绍。
Word Wide Wed是怎样运行的呢?在浏览器上键入一个正确的网址后,若一切顺利,网页就出现了。
使用浏览器从网站获取HTML页面时,实际在使用超文本传输协议。
HTTP规定了信息在Internet上的传输方法,特别是规定吧浏览器与服务器的交互方法。
从网站获取页面时,浏览器在网站上打开了一个对网络服务器的连接,并发出请求。
服务器收到请求后回应,所以HTTP协议的核心就是“请求和响应”。
一个典型的请求通常包含许多头,称作请求的HTTP头。
头提供了关于信息体的附加信息及请求的来源。
其中有些头是标准的,有些和特定的浏览器有关。
一个请求还可能包含信息体,例如,信息体可包含HTML表单的内容。
在HTML表单上单击Submit 键时,该表单使用ACTION=”POST”或ACTION=”GET”方法,输入表单的内容都被发送到服务器上。
该表单内容就由POST方法或GET方法在请求的信息体中发送。
服务器发送请求时,返回HTTP响应。
响应也有某种结构,每个响应都由状态行开始,可以包含几个头及可能的信息体,称为响应的HTTP头和响应信息体,这些头和信息体由服务器发送给客户的浏览器,信息体就是客户请求的网页的运行结果,对于JSP 页面,就是网页的静态信息。
用户可能已经熟悉状态行,状态行说明了正在使用的协议、状态代码及文本信息。
例如,若服务器请求出错,则状态行返回错误及对错误描述,比如HTTP/1.1 404 Object Not Found。
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 JSP( 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 Web application that establishes the high dynamic state. According to the Sun parlance, the JSP can adapt to include the Apache WebServer, IIS4.0 on the market 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 GENERALIZEThe 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 appropriate in 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 you choose.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 appropriate tool for the job, and servlets, by themselves, do not complete your 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 changes according 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 need not 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 progressto 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 own purposes. 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 the aforementioned 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 also allows 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 theexpression 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 and efficiently. 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 Web application 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)。
第1章JSP概述JSP(Java Server Pages)是由Sun公司以Java语言为脚本语言开发出来的一种动态网页制作技术,主要完成网页中服务器动态部分的编写。
该技术是在Servlet技术的基础上形成的,并继承了Java语言的多种优势,如安全性、支持多线程、平台无关性等。
与其他动态网页技术相比较,如ASP、PHP等,具有运行速度快、安全等特点。
本章将简要介绍JSP的产生到现状,并重点介绍构建JSP的运行平台,即Tomcat和JDK的安装及配置。
在本章最后给出一个JSP+JavaBean+Servlet实例,演示JSP各部分的运行情况。
➢了解Web技术的产生和发展。
➢了解JSP的产生和应用。
➢了解JSP的技术优势。
➢掌握常见JSP的设计模式。
➢掌握JDK下载、安装、配置。
➢掌握Tomcat下载、安装。
➢掌握编写JSP工作原理。
➢了解JSP页面包含元素。
➢了解JSP的开发流程。
1.1 JSP简介要熟练掌握JSP技术,首先需要了解JSP的产生和发展历史,明确JSP技术在Web技术中所占有位置,JSP技术能够解决的问题。
在本小节中,将主要介绍JSP形成的必然原因,与其他动态技术相比所具有的优势。
等,都得到了广泛应用。
JSP是它们中的佼佼者。
JSP(Java Server Pages)是由Sun Microsystem公司于1999推出的新技术,是基于Java Servlet 以及整个Java体系的Web开发技术。
利用这一技术可以建立先进、安全和跨平台的动态网站。
在传统的网页HTML文件(*.htm,*.html)中加入Java程序片段(Scriptlet)和JSP标记,就构成了JSP网页(*.jsp)。
Web服务器在收到访问JSP网页的请求时,首先执行其中的程序片段,然后将执行结果以HTML格式返回给客户。
程序片段可以操作数据库、重新定向网页、发送E-mail 等等,这就是建立动态网站所需要的功能。
毕业设计(论文)外文文献翻译文献、资料中文题目:SP及其WEB技术文献、资料英文题目:文献、资料来源:文献、资料发表(出版)日期:院(部):专业:班级:姓名:学号:指导教师:翻译日期: 2017.02.14外文翻译原文及译文JSP and WEB technolog1 JSP IntroductionJSP (JavaServer Pages) is a Java-based scripting technology. Is advocated by Sun Microsystems Inc., together with a number of companies involved in the establishment of a dynamic web page technology standards. JSP technology is somewhat similar to ASP technology, It is a traditional HTML page file (*. htm, *. html) to insert Java program segment (Scriptlet) and JSP tag (tag), To form the JSP file(*jsp). Web development with JSP is a cross-platform applications that can run under Linux, but also in other operating systems. In the JSP of the many advantages, one of which is that it will be HTML encoded Web page from the business logic separated effectively. JSP access with reusable components, such as Servlet, JavaBean and Java-based Web applications. JSP also supports directly in the Web page embedded Java code. JSP can be used two ways to access documents: JSP documents sent by the browser request, the request sent to the Servlet. JSP technology uses Java programming language, XML-type tags and scriptlets, to have a package deal with the logic of dynamic pages. Page tags and scriptlets can also exist in the server access to the resources of the application logic. JSP logic and Web page design and display isolated and support reusable component-based design, Web-based applications more quickly and easily developed.The Web server when meets visits the JSP homepage the request, first carries out segment, will then carry out the result code to return together with JSP in the document HTML for the customer. The insertion Java segment may operate the database, again the directional homepage and so on, realizes the function which the establishment dynamic homepage needs. JSP and Java Servlet are the same, is in the server end execution, usually returns to this client side is a HTML text, therefore client side, so long as has the browser to be able to glance over.The JSP page is composed of the HTML code and the inserting Java code. The server in the page by the client side was requested that later will carry on processing to these Java code, will then produce the HTML page will return gives the client side thebrowser. Java Servlet is the JSP technology base, moreover the large-scale Web application procedure's development needs Java Servlet and the JSP coordination can complete. JSP had the Java technology simply easy to use, complete object-oriented, had the platform independency, and safe reliable, mainly faced Internet's all characteristics.2 JSP computing techniqueTo carry on the dynamic website conveniently fast the development, JSP has made the improvement in the following several aspects, causes it to become builds the cross platform fast the dynamic website first choice plan.2.1 carries on the content production and the demonstration separatesWith the JSP technology, the Web page development personnel may use HTML or the XML marking design and the formatted final page, and uses the JSP marking or the tootsy produces on page's dynamic content originally. Production content's logic is sealed in marks and in the JavaBeans module, and ties up in the script, all scripts in server end movement. Because core logic is sealed in marks and in JavaBeans, therefore the Web administrative personnels and the page designer, can edit and use the JSP page, but does not affect the content the production. In the server end, the JSP engine explained that the JSP marking and the script, produce the content which requested, and (or XML) page's form transmits the result by HTML the browser. This both are helpful in the author protects own code, and can guarantee any based on the HTML Web browser's complete usability.2.2 may entrust with heavy responsibility the moduleThe overwhelming majority JSP page relies on may entrust with heavy responsibility, the cross platform module (JavaBeans or Enterprise the JavaBeans module) carries out complex processing which the application procedure requests. The development personnel can share and exchange the execution ordinary operation the module, or causes these modules uses for more users and the customer association. Has accelerated the overall development process based on module's method, and causes each kind of organization obtains balanced in their existing skill and in the optimized result development endeavor.2.3 uses markingThe Web page development personnel will not be the familiar script languageprogrammers. The JSP technology has sealed many functions, these functions are easy to use, marking to carry on the dynamic content production with JSP in the related XML to need. The standard JSP marking can visit and the instantiation JavaBeans module, the establishment or the retrieval module attribute, downloads Applet, as well as the execution difficulty with codes and the time-consuming function with other methods.2.4 adapts the platformNearly all platforms support Java, JSP+JavaBeans to be possible to pass unimpeded nearly under all platforms. Transplants from a platform to other platform, JSP and JavaBeans does not even need to translate, because the Java byte code is standard has nothing to do with the platform.2.5 database connectionIn Java connects the database the technology is the JDBC, Java procedure is connected through the JDBC driver and the database, operations and so on execution inquiry, extraction data. Sun Corporation has also developed JDBC-ODBC bridge, uses this technical Java procedure to be possible to visit has the ODBC driver database, at present the majority database systems have the ODBC driver, therefore the Java procedure can visit such as Oracle, Sybase, MS SQL Server and databases and so on MS Access. In addition, through the development marking storehouse, the JSP technology may further expand. The third party development personnel and other personnel may found their marking storehouse for the commonly used function. This enables the Web page development personnel to be able to use the familiar tool and to be similar to marking same carries out the specific function component to carry on the work. The JSP technology very easy conformity to many kinds of application architecture, to use the extant tool and the skill, and can expand to the support enterprise distributional application.3 Eclipse function synopsisMore and more Java development personnel already started the productivity which and the quality income appreciates Eclipse JDT to provide. It was the Java editor provides grammar Gao Liang to demonstrate that the formatting, the fold, the content were auxiliary, code template and so on many functions. It grows unceasingly available restructuring and the code generation function set permits you in a higher rank the operation code, andautomated usual code intensity duty and easy wrong duty. Moreover, in develops the code and uses JDT to compile and to carry out the JUnit test built-in support carries on the unit testing after the code, may use Eclipse the first-class Java debugger debugging when the movement meets any question. Besides JDT, Eclipse SDK- the most popular downloading - also contains Plug-in Development Environment(PDE). PDE used the specific function to expand JDT to construct the Eclipse plug-in unit - based on the Eclipse application procedure basic construction agglomeration. In fact, uses the tool which provides by Eclipse itself to be able to surmount the Java development, may expand the existing Eclipse application procedure, or even founds the brand-new application procedure.Eclipse by a script level constitution, contains in many functional modules or the Eclipse terminology so-called “the plug-in unit”. The plug-in unit is provides all functions in the Eclipse application procedure the module. They cooperate through its API to pay the final outcome together. In Eclipse, even the most foundation's function, for instance the search and the start installment's plug-in unit, seals in the plug-in unit. In order to expand the existing Eclipse function or carry on the construction in above, the plug-in unit the concrete expansion contribution for the expansion spot which will expose by other plug-in units. Usually, the plug-in unit concentrates the specific region responsibility, and gives through or a many expansion way other responsibility designation other plug-in units. For example, a plug-in unit allows you parallel to compare two documents visibly the contents, but it will not care how to read these documents even how to explain these document structure; This is other plug-in unit's work. When compared with two documents, this plug-in unit first inspects whether to have another plug-in unit to be possible to explain these document structure. If found one, it to the plug-in unit inquiry related file organization information which found, and used this information in the comparison process.May see that the modular construction was Eclipse has provided the huge flexibility, and provided one to be possible to support the massive application procedure platform which the original design has not expected.4 Structs function synopsisStruts is a MVC frame (Framework), uses in developing Java fast the Web application.Struts realizes the key point in C(Controller), Action which and we have custom-made including ActionServlet/RequestProcessor, was also V(View) provides a series of rows to have custom-made the label (Custom Tag). Spring is a light vessel (light-weight container), its core is the Bean factory (Bean Factory), with constructs M(Model) which we need. Above this foundation, Spring has provided AOP (Aspect-Oriented Programming, face stratification plane programming) realization, provides under the non-management environment with it to declare services and so on way business, security; Is more convenient to Bean factory expansion ApplicationContext we to realize the J2EE application; DAO/ORM realizes facilitates us to carry on the database the development; Web MVC and Spring Web have provided Java the Web application frame or carries on the integration with other popular Web frame. That is may a both use, achieve both own characteristic carries on supplementary.Structs is the kind which, servlet and the JSP mark a group cooperates mutually, they compose the MVC 2 designs which may entrust with heavy responsibility. This definition expressed that Struts is a frame, but is not a storehouse, but Struts has also contained the rich mark storehouse and the independence in this frame work utility program class.Client browser (customer browser), the request founds an event from customer browser's each HTTP. The Web vessel will use a HTTP response to make the response.Controller (controller), the controller receive from browser's request, and decided that sends out where this request. Speaking of Struts, the controller is an order design pattern which realizes by servlet. struts-config.xml document disposition controller.Service logic, the service logic renewal model's condition, and helps the control application procedure the flow. Speaking of Struts, this is through takes the actual service logic “thin” the packing Action kind to complete.Model (model) condition, model expression application procedure condition. Service object renewal application procedure condition. ActionForm bean in conversation level or request level expression model condition, but is not in the lasting level. The JSP document uses JSP to mark the read from the ActionForm bean information.View (view), the view is a JSP document. And does not have the flow logic, does not have the service logic, also does not have the model information -- Only then marks. The mark causes Struts is different with other frames (for example Velocity) one of factors.Just like the Struts controller is (event usually is HTTP post) maps the event kind of。
中英文对照外文翻译文献(文档含英文原文和中文翻译)JSP and WEB technolog1 JSP IntroductionJSP (JavaServer Pages) is a Java-based scripting technology. Is advocated by Sun Microsystems Inc., together with a number of companies involved in the establishment of a dynamic web page technology standards. JSP technology is somewhat similar to ASP technology, It is a traditional HTML page file (*. htm, *. html) to insert Java program segment (Scriptlet) and JSP tag (tag), To form the JSP file(*jsp). Web development with JSP is a cross-platform applications that can run under Linux, but also in other operating systems. In the JSP of the many advantages, one of which is that it will be HTML encoded Web page from the business logic separated effectively. JSP access with reusable components, such as Servlet, JavaBean and Java-based Web applications. JSP also supports directly in the Web page embedded Java code. JSP can be used two ways to access documents: JSP documents sent by the browser request, the request sent to the Servlet. JSP technology uses Java programming language, XML-type tags and scriptlets, to have a package deal with the logic of dynamic pages. Page tags and scriptlets can also exist in the server access to the resources of the application logic. JSP logic and Web page design and display isolated and support reusable component-based design, Web-based applications more quickly and easily developed.The Web server when meets visits the JSP homepage the request, first carries out segment, will then carry out the result code to return together with JSP in the document HTML for the customer. The insertion Java segment may operate the database, again the directional homepage and so on, realizes the function which the establishment dynamic homepage needs. JSP and Java Servlet are the same, is in the server end execution, usually returns to this client side is a HTML text, therefore client side, so long as has the browser to be able to glance over.The JSP page is composed of the HTML code and the inserting Java code. The server in the page by the client side was requested that later will carry on processing to these Java code, will then produce the HTML page will return gives the client side the browser. Java Servlet is the JSP technology base, moreover the large-scale Web applicationprocedure's development needs Java Servlet and the JSP coordination can complete. JSP had the Java technology simply easy to use, complete object-oriented, had the platform independency, and safe reliable, mainly faced Internet's all characteristics.2 JSP computing techniqueTo carry on the dynamic website conveniently fast the development, JSP has made the improvement in the following several aspects, causes it to become builds the cross platform fast the dynamic website first choice plan.2.1 carries on the content production and the demonstration separatesWith the JSP technology, the Web page development personnel may use HTML or the XML marking design and the formatted final page, and uses the JSP marking or the tootsy produces on page's dynamic content originally. Production content's logic is sealed in marks and in the JavaBeans module, and ties up in the script, all scripts in server end movement. Because core logic is sealed in marks and in JavaBeans, therefore the Web administrative personnels and the page designer, can edit and use the JSP page, but does not affect the content the production. In the server end, the JSP engine explained that the JSP marking and the script, produce the content which requested, and (or XML) page's form transmits the result by HTML the browser. This both are helpful in the author protects own code, and can guarantee any based on the HTML Web browser's complete usability.2.2 may entrust with heavy responsibility the moduleThe overwhelming majority JSP page relies on may entrust with heavy responsibility, the cross platform module (JavaBeans or Enterprise the JavaBeans module) carries out complex processing which the application procedure requests. The development personnel can share and exchange the execution ordinary operation the module, or causes these modules uses for more users and the customer association. Has accelerated the overall development process based on module's method, and causes each kind of organization obtains balanced in their existing skill and in the optimized result development endeavor.2.3 uses markingThe Web page development personnel will not be the familiar script language programmers. The JSP technology has sealed many functions, these functions are easy touse, marking to carry on the dynamic content production with JSP in the related XML to need. The standard JSP marking can visit and the instantiation JavaBeans module, the establishment or the retrieval module attribute, downloads Applet, as well as the execution difficulty with codes and the time-consuming function with other methods.2.4 adapts the platformNearly all platforms support Java, JSP+JavaBeans to be possible to pass unimpeded nearly under all platforms. Transplants from a platform to other platform, JSP and JavaBeans does not even need to translate, because the Java byte code is standard has nothing to do with the platform.2.5 database connectionIn Java connects the database the technology is the JDBC, Java procedure is connected through the JDBC driver and the database, operations and so on execution inquiry, extraction data. Sun Corporation has also developed JDBC-ODBC bridge, uses this technical Java procedure to be possible to visit has the ODBC driver database, at present the majority database systems have the ODBC driver, therefore the Java procedure can visit such as Oracle, Sybase, MS SQL Server and databases and so on MS Access. In addition, through the development marking storehouse, the JSP technology may further expand. The third party development personnel and other personnel may found their marking storehouse for the commonly used function. This enables the Web page development personnel to be able to use the familiar tool and to be similar to marking same carries out the specific function component to carry on the work. The JSP technology very easy conformity to many kinds of application architecture, to use the extant tool and the skill, and can expand to the support enterprise distributional application.3 Eclipse function synopsisMore and more Java development personnel already started the productivity which and the quality income appreciates Eclipse JDT to provide. It was the Java editor provides grammar Gao Liang to demonstrate that the formatting, the fold, the content were auxiliary, code template and so on many functions. It grows unceasingly available restructuring and the code generation function set permits you in a higher rank the operation code, and automated usual code intensity duty and easy wrong duty. Moreover, in develops the codeand uses JDT to compile and to carry out the JUnit test built-in support carries on the unit testing after the code, may use Eclipse the first-class Java debugger debugging when the movement meets any question. Besides JDT, Eclipse SDK- the most popular downloading - also contains Plug-in Development Environment(PDE). PDE used the specific function to expand JDT to construct the Eclipse plug-in unit - based on the Eclipse application procedure basic construction agglomeration. In fact, uses the tool which provides by Eclipse itself to be able to surmount the Java development, may expand the existing Eclipse application procedure, or even founds the brand-new application procedure.Eclipse by a script level constitution, contains in many functional modules or the Eclipse terminology so-called “the plug-in unit”. The plug-in unit is provides all functions in the Eclipse application procedure the module. They cooperate through its API to pay the final outcome together. In Eclipse, even the most foundation's function, for instance the search and the start installment's plug-in unit, seals in the plug-in unit. In order to expand the existing Eclipse function or carry on the construction in above, the plug-in unit the concrete expansion contribution for the expansion spot which will expose by other plug-in units. Usually, the plug-in unit concentrates the specific region responsibility, and gives through or a many expansion way other responsibility designation other plug-in units. For example, a plug-in unit allows you parallel to compare two documents visibly the contents, but it will not care how to read these documents even how to explain these document structure; This is other plug-in unit's work. When compared with two documents, this plug-in unit first inspects whether to have another plug-in unit to be possible to explain these document structure. If found one, it to the plug-in unit inquiry related file organization information which found, and used this information in the comparison process.May see that the modular construction was Eclipse has provided the huge flexibility, and provided one to be possible to support the massive application procedure platform which the original design has not expected.4 Structs function synopsisStruts is a MVC frame (Framework), uses in developing Java fast the Web application. Struts realizes the key point in C(Controller), Action which and we have custom-madeincluding ActionServlet/RequestProcessor, was also V(View) provides a series of rows to have custom-made the label (Custom Tag). Spring is a light vessel (light-weight container), its core is the Bean factory (Bean Factory), with constructs M(Model) which we need. Above this foundation, Spring has provided AOP (Aspect-Oriented Programming, face stratification plane programming) realization, provides under the non-management environment with it to declare services and so on way business, security; Is more convenient to Bean factory expansion ApplicationContext we to realize the J2EE application; DAO/ORM realizes facilitates us to carry on the database the development; Web MVC and Spring Web have provided Java the Web application frame or carries on the integration with other popular Web frame. That is may a both use, achieve both own characteristic carries on supplementary.Structs is the kind which, servlet and the JSP mark a group cooperates mutually, they compose the MVC 2 designs which may entrust with heavy responsibility. This definition expressed that Struts is a frame, but is not a storehouse, but Struts has also contained the rich mark storehouse and the independence in this frame work utility program class.Client browser (customer browser), the request founds an event from customer browser's each HTTP. The Web vessel will use a HTTP response to make the response.Controller (controller), the controller receive from browser's request, and decided that sends out where this request. Speaking of Struts, the controller is an order design pattern which realizes by servlet. struts-config.xml document disposition controller.Service logic, the service logic renewal model's condition, and helps the control application procedure the flow. Speaking of Struts, this is through takes the actual service logic “thin” the packing Action kind to complete.Model (model) condition, model expression application procedure condition. Service object renewal application procedure condition. ActionForm bean in conversation level or request level expression model condition, but is not in the lasting level. The JSP document uses JSP to mark the read from the ActionForm bean information.View (view), the view is a JSP document. And does not have the flow logic, does not have the service logic, also does not have the model information -- Only then marks. The mark causes Struts is different with other frames (for example Velocity) one of factors.Just like the Struts controller is (event usually is HTTP post) maps the event kind of servlet. you to expect - the air-operated controller use configuration files to cause you notto need to carry on to these values the hard code. The time has changed, but method as before.The Action kind, ActionForm maintains the Web application procedure the conversation condition. ActionForm is one abstract class, must found this kind of subclass for each input form model. When I said when input form model, what refers to the ActionForm expression is establishes or in the renewal general sense data by the HTML form.The Action kind is service logic packing. A Action kind of use is transforms HttpServletRequest into the service logic. Must use Action, please found its subclass and covers process () the method.ActionServlet (Command) will use perform () the method the parametrization kind to transmit for ActionForm. Still did not have too many repugnant request.getParameter () to transfer. When the event progresses to this step, the input form data (or HTML form data) has been withdrawn from the request class and shifts to the ActionForm kind.Considered that a Action kind of another way is the Adapter design pattern. The Action use will be “a kind of connection will transform another connection which will need for the client. Adapter enables the kind the joint operation, if does not have Adapter, then these kinds will be unable because of the incompatible connection the joint operation.”. In this example's client is ActionServlet, it knows nothing about to our concrete service class connection. Therefore, Struts has provided a service connection which it can understand, namely Action. Through expands Action, we cause our service connection and the Struts service connection maintain compatible.5 CSS synopsisThe CSS edition method is the same with HTML, may also be any text editor or the homepage edition software, but also has uses for to edit CSS specially the software. If you write the CSS sentence regards the exterior cascading style sheet, but transfers in the HTML document, then its extension saves .css to be possible. Initially the technical personnel found out HTML, mainly stresses on the definition content, for instance expressed that a paragraph, indicates the title, but excessively has not designed HTML the typesetting and the contact surface effect.Along with the Internet rapid development, HTML is widely applied, the surfer people hoped certainly that the homepage makes attractive, therefore the HTMLtypesetting and the contact surface effect's limitation exposes day by day. In order to solve this problem, the people also took many tortuous paths, has used some not good method, for instance increases many attribute results to HTML becomes the code very extremely fat, turns the picture the text, excessively many comes the typesetting using Table, expresses the white space with the blank picture and so on. Appears until CSS.CSS may be a homepage design breakthrough, it has solved the homepage contact surface typesetting difficult problem. May such say that HTML Tag is mainly defines the homepage content (Content), but CSS decided how these homepage content does demonstrate (Layout). The CSS English is Cascading Style Sheets, Chinese may translate the tandem cascading style sheet. CSS may divide into three kinds according to its position: In inlays the style (Inline Style), internal cascading style sheet (Internal Style Sheet), exterior cascading style sheet (External Style Sheet).6 HTML function synopsisHyper Text Markup the Language hypertext mark language is one kind uses for to manufacture the hypertext documents the simple mark language. The hypertext documents which compiles with HTML are called the HTML documents, it can the independence in each kind of operating system platform (for example UNIX, WINDOWS and so on). HTML has served as since 1990 on World Wide Web the information to express the language, uses in describing the Homepage form design and it and on WWW the other Homepage linked information.The HTML documents (i.e. the Homepage source document) was one has laid aside the mark ASCII text document, usually it had .html or the .htm document extension. Produces HTML documents mainly to have the following three ways: 1. the manual direct compilation (e.g. ASCII text editor which or other HTML edition tool likes with you). 2. will have other form documents through certain format conversion tool (for example the WORD documents) to transform the HTML documents. 3. by the Web server (or said that the HTTP server) one only then real-time dynamic produces. the HTML language is through uses each kind of mark (tags) to mark the documents the structure as well as marks the ultra chain (Hyperlink) the information.Although the HTML language described the documents structure form, but how can't define the documents information to precisely demonstrate and arrange, but is onlysuggested how the Web browser (for example Mosiac, Netscape and so on) should demonstrate and arrange these information, is decided finally in front of user's demonstration result by the Web browser's demonstration style and to the mark explanatory ability. Why is the identical documents the effect which demonstrated in the different browser meets is dissimilar. At present the HTML language's edition is 2.0, it is based on SGML (Standard Generalized Markup Language, standard sets at sign language generally, as soon as is applies mechanically describes digitized documents structure and manages its content complex standard) a subset to evolve comes. Although in next edition's standard HTML3.0 (is also called HTML+) to draw up, but some the partial experimental nature draft standard widely has been used, the mostly outstanding Web browser (for example Netscape and so on) can explain in the HTML3.0 part new mark, therefore introduced in this chapter some HTML3.0 new mark has been accepted by the most browsers.7 Js script language synopsisJS is javascrip, Javascript is one kind the script language which comes by the Netscape LiveScript development, the main purpose is to solve the server terminal language, for instance Perl, carry-over speed question. At that time served the end to need to carry on the confirmation to the data, because the network speed was quite slow, only then 28.8kbps, the confirmation step waste's time were too many. Therefore Netscape browser Navigator has joined Javascript, has provided the data confirmation basic function.The JavaScript official name is “ECMAScript”. This s tandard by ECMA organization development and maintenance. ECMA-262 is the official JavaScript standard. This standard based on JavaScript (Netscape) and JScript (Microsoft). Netscape (Navigator 2.0) Brendan Eich has invented this language, started from 1996, already appeared in all Netscape and in the Microsoft browser. The ECMA-262 development began in 1996, in 1997 July, the ECMA general meeting has accepted its first edition.Script script uses one specific descriptive language, rests on certain form compilation to be possible the execution document, is also called as great or the batch run document. The script usually may transfer temporarily by the application procedure and carry out. Each kind of script present widely is applied in the homepage design, because the script not only may reduce the homepage the scale and raises the homepage browsing speed,moreover may enrich the homepage performance, like animation, sound and so on. Cites a most common example, when we click in the homepage the E-mail address can transfer Outlook Express or the Foxmail this kind of mail software automatically, is realizes through the script function. Also because of script these characteristics, the human who harbors ulterior motives by some are often using. For example joins some destruction computer system's order in the script, like this works as the user browsing homepage, once transfers this kind of script, will then cause the user the system to come under the attack. Therefore the user should act according to visits homepage the trust degree selective security rank, specially regarding these itself content on the illegal homepage, do not permit the use script easily. Through “the safe establishment” the dialog box, the choice “the script” under option each kind of estab lishment may with ease realize to script being forbid and begins using.Present's script language is quite many, script language execution generally only with concrete explanation actuator related, so long as therefore on the system has the corresponding language interpreter to be possible to achieve the cross platform. Script (Script), is includes order and so on bind and alias sets, you may save this set are an independent document then in the time which needs carries out, like this may facilitate you in the CS use. The script may save for the suffix named .cfg document places under the cstrike folder, when execution in control bench input: exec (script filename) .cfg then. For instance saves a script is the buys.cfg document, inputs in the control bench: execbuys.cfg may realize the function which we need. Must realize an order, so long as is good this process definition (alias), and assigns a key position for this order, so long as later according to will assign the good key position, may realize this proceJSP及其WEB技术. 1 JSP简介JSP(JavaServer Pages)是一种基于Java的脚本技术。
JSP介绍J2EE(Java2企业版)已经承担起了曾经很混乱的建立互联网平台的任务,并使开发者们能够使用Java来高效地创建多层服务器端应用程序。
现今,Java企业版的API已经扩展为涵盖了众多领域:用于远程对象处理的RMI和CORBA,用于数据库交互的JDBC,用于访问命名和目录服务的JNDI,用于创建可重用商务组件的企业级JavaBeans(EJB),用于面向消息的中间件的JMS TM(Java Messaging Service,Java消息服务),用于XML处理的JAXP TM,以及用于执行原子性(atomic)事务的JTA TM(Java Transaction API,Java事务API)。
另外,J2EE还支持servlets是一种非常流行的用于替代CGI脚本的Java小程序。
这些技术的组合使得程序员可以为各种不同的任务创建分布式的商务解决方案。
在1999年末,Sun Microsystems公司向企业级Java工具集中加入了一个新的元素:Java Server Pages(JSP,Java服务器页面)。
JSP建立在Java servlet之上,它的设计目的是使程序员乃至非程序员都能高效地创建Web内容。
什么是JSP?简明扼要地说,JSP是一种用来开发含有动态内容网页的技术。
纯HTML页面只包含静态的内容,它的内容通常保持不变,而JSP页面则不同,它可以根据任意数量的变量来改变自己的内容,这些变量包括用户的身份信息,用户使用的浏览器类型,用户提供的信息,以及用户所做的选择等。
JSP页面就和常规的网页一样,包含标准的标记语言元素,例如HTML的标签。
然而,JSP页面还包含特殊的JSP元素,这些元素使得服务器可以把动态内容插入到网页中。
JSP 元素的用途非常广泛,例如从数据库取得信息,或记录用户的个性信息。
当用户请求一个JSP页面时,服务器先执行JSP元素,并把结果同网页的静态部分相结合,然后把动态合成后的页面送回到浏览器。
JSP定义了许多用于Web应用程序的有用的标准元素,例如访问JavaBeans组件的元素,在页面间传递控制权的元素,以及在请求,页面和用户间共享信息的元素。
程序员也可以通过使用应用程序的专用元素来扩展JSP语法,从而完成像访问数据库和EJB,发送电子邮件,生成表示应用程序专用数据的HTML这样的任务,与JSP规范相关的规范(JSTL规范)定义了一组这种常用的自定义元素。
标准元素和自定义元素的组合确保了可以开发出强大的Web 应用程序。
为什么要使用JSP?在Web发展的早期,CGI(Common Gateway Interface,公共网关接口)是开发动态Web 内容的唯一工具,然而,CGI并非一种高效率的解决方案。
对每一个传来的请求,Web服务器都必须创建一个新的操作系统进程,载入一个解释器和一个脚本,接着执行这个脚本,然后再把这些全部释放掉。
这使得服务器承受着繁重的负担,而且当通信量增加时性能会变得很低。
过去几年里,出现了许多CGI的替代品和增强版,例如FastCGI,Apache的mod_perl,Netscape的NSAPI,Microsoft的ISPAI和Sun Microsystems的Java servlet。
虽然这些解决方案能提供更高的性能和可缩放性,但是所有这些技术都面临着同一个问题:它们都是通过把HTML代码直接嵌入到程序语言代码中来生成网页。
这使得动态网页的创建成为程序员所独立的领域。
然而,JSP改变了这一切。
在HTML页面中嵌入动态元素JSP从一个角度来处理这个问题。
JSP允许将特殊的活性元素嵌入到HTML页面中,而不是将HTML语言嵌入到编程代码中。
这些元素看起来与HTML元素类似,但它们实际上是组件化的Java程序,当用户请求页面时,服务器便会执行该程序。
下面这个简单的JSP页面解释了这一点:<% taglib prefix=”c” url=”/jstl/core”%><Html><body bgcolor=”white”><jsp: usebean id=”clock” class=”java.util.Date” /><C: choose><c: when teat=”s {clock.hours<12}”><h1>Good morning! </h1></c: when><c: when test=”s {clock.hours < 18}”><h1>Good day! </h1></c: when><c: otherwise><h1>Good evening! </h1></c: otherwise></c: choose>Welcome to our site, open 24 hours a day.</body></html>这个页面根据当天的时间向用户发去了不同的消息:如果当地时间是在中午12:00之前,则发送“Good morning!”;如果是在中午12:00到晚6:00之间,则发送“Good day!”;如果是在晚6:00之后,则发送“Good evening!”。
当用户请求这个页面时,支持JSP的Web服务器就会执行由黑体的Java元素所代表的逻辑判断,并创建一个HTML页面,把它发送回用户的浏览器。
例如,如果现在的时间是晚上8:53,那么从服务器发回到浏览器的结果页面就会是这个样子:<Html><body bgcolor=”white”><h1>Good evening! </h1>Welcome to our site, open 24 hours a day.</body></html>除了与HTML类似的JSP元素外,JSP页面还可以包含嵌入在所谓“脚本元素(scripting element)”中的Java代码。
从JSP规范的第一个版本开始,这种功能已经是其中的一部分了,而且它对于简单的条件逻辑来说也非常方便。
但是,随着新的JSP Standard Tag Library (JSTL)的引入,Java代码在页面中其实很少用到。
此外,在Web页面中嵌入过多的代码就像在服务器端程序中使用HTML元素一样,通常会使Web应用程序难以维护和调试。
人尽其用正如前面所述,JSP可以把HTML这样的标记语言代码和用来处理用户输入、访问数据库以及执行其他应用任务的编程语言代码分离开来。
这种分离任务的一种表现方式就是JSP 标准和自定义元素的使用;这些元素是用编程代码来实现的,在使用方式上,它们与通常网页中用到的页面标记元素相同。
另一种分离方式是将JSP与其他J2EE技术组合起来。
例如,Java servlet可以处理用户输入,Enterprise JavaBeans(EJB)可以控制应用程序逻辑,JSP页面则可以提供用户界面。
这种分离意味着,企业使用JSP就可以按员工各自擅长的专业技术把他们分成两组:一支JSP Web开发队伍,其中一部分程序员将应用程序所需要的逻辑实现为servlet,EJB和自定义的JSP元素,另一部分是网页设计师,他们对界面了然于胸,并在无需做任何编程工作的情况下使用强大的自定义元素。
与企业级Java API集成最后,因为JSP是建立在Java Servlets API之上的,所以JSP可以使用所有强大的企业级Java API,其中包括:●JDBC●RMI(Romote Method Invocation,远程方法调用)和OMG CORBA支持●JNDI(Java Naming and Directory Interface,Java命名和目录接口)●EJB(Enterprise JavaBeans)●JMS(Java McssageService,Java消息服务)●JTA(Java Transaction AP,Java事务API)●JAXP(Java API for XML Processing)●JavaMail这意味着可以轻易地把JSP和已有的Java企业级解决方案集成起来。
Java servlet模板引擎Java servlet模板引擎是另一种把外观呈现过程和处理过程分开的技术。
当servlet 得到普遍使用时,开发者们很快就意思到,将HTML代码直接嵌入到servlet的Java代码中后,增加了对外观呈现部分的维护难度。
因此,许多称为模板引擎(template engine)的开源工具被开发出来,题目可用于从servlet中把HTML提取出来。
这些模板引擎用来和纯代码组件(servlet)协同工作,而且只使用包含脚本语言的Web页面,专用于外观呈现部分。
请求被发送给某个servlet,由该servlet进行处理,然后创建表示处理结果的对象,并调用一个网页模板来生成HTML代码,最后将HTML代码返回给浏览器。
模板包括与前面所讲述的替代方案近似的脚本代码。
然而,这些引擎所使用的脚本语言在功能上跟弱一些,因为脚本仅仅用来读入数据对象和生成HTML代码,以显示对象的值。
所有其他的产品和技术支持通用语言,这些语言(不论好坏)可以用于在页面中包括商务逻辑。
JSP的优点下面是上述替代方案中的一些最重要的特性:●JSP同时支持脚本产生的动态内容和基于元素的动态内容,并且允许程序员们开发自定义的标记库,来满足应用程序特定的需要。
●JSP页面可以进行预编译,从而提高了服务器处理的效率。
●JSP页面可以与主管商务逻辑的servlet组合起来使用,Java servlet模板引擎支持这种模型。
另外,JSP还有许多独有的优点,使得它出类拔萃:●JSP是一种规范,而不是一个产品。
这意味着厂商们可以用各种不同的实现方式相互竞争,从而使性能和质量不断提高。
这还带来了一种不太明显的好处,也就是当许多公司在技术上投入时间和金钱之时,有可能要很长时间才会有成果,而JSP作为规范则能适当四保证新版本与以前的版本想兼容;而如果是私有技术,则通常不是这样。
JSP是J2EE的必备部分,而J2EE是用于企业级应用程序的完整平台。
这意味着JSP同时适用于最简单的应用程序和最复杂、最苛刻的应用程序。