外文翻譯--jsp及其web技術

1、<p><b>　　外文翻譯原文及譯文</b></p><p><b>　　沈陽航空航天大學</b></p><p><b>　　2012年6月</b></p><p>　學 院計算機學院</p><p>　專 業(yè)計算機科學與技術</p>&

2、lt;p>　班 級8401010x</p><p>　學 號20080401010xx</p><p>　姓 名</p><p>　指導教師</p><p>　負責教師</p><p>　　JSP and WEB technolog</p><p>　　1 JSP Int

3、roduction</p><p>　　JSP (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

4、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）. W

5、eb development with JSP is a cross-platform applications that can run under Linux, but also </p><p>　　The Web server when meets visits the JSP homepage the request, first carries out segment, will then carry

6、 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 estab

7、lishment 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, </p><p>　　The JSP page is compos

8、ed 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 clien

9、t side the browser. 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 simp

10、ly easy to use, complete object-oriented, </p><p>　　2 JSP computing technique</p><p>　　To carry on the dynamic website conveniently fast the development, JSP has made the improvement in the foll

11、owing several aspects, causes it to become builds the cross platform fast the dynamic website first choice plan.</p><p>　　2.1 carries on the content production and the demonstration separates</p><

12、;p>　　With 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 origi

13、nally. 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 W

14、eb administrative personnels and the page designer, can edit and use the JSP</p><p>　　2.2 may entrust with heavy responsibility the module</p><p>　　The overwhelming majority JSP page relies on m

15、ay 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

16、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

17、 each kind of orga</p><p>　　2.3 uses marking</p><p>　　The Web page development personnel will not be the familiar script language programmers. The JSP technology has sealed many functions, these

18、 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 retr

19、ieval module attribute, downloads Applet, as well as the execution difficulty with codes and the time-consuming function with other methods.</p><p>　　2.4 adapts the platform</p><p>　　Nearly all

20、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 c

21、ode is standard has nothing to do with the platform.</p><p>　　2.5 database connection</p><p>　　In Java connects the database the technology is the JDBC, Java procedure is connected through the J

22、DBC 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 da

23、tabase, 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</p><p>　　3 Eclipse functi

24、on synopsis</p><p>　　More 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 Lia

25、ng 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 high

26、er rank the operation code, and automated usual code intensity duty and easy wrong duty. Moreo</p><p>　　Eclipse by a script level constitution, contains in many functional modules or the Eclipse terminology

27、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 founda

28、tion'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 co</p><p>　　May see that

29、 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.</p><p&

30、gt;　　4 Structs function synopsis</p><p>　　Struts 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-

31、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

32、Factory), with constructs M(Model) which we need. Above this foundation, Spring has provided AOP (Aspect-Oriented P</p><p>　　Structs is the kind which, servlet and the JSP mark a group cooperates mutually, t

33、hey 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 indepen

34、dence in this frame work utility program class.</p><p>　　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

35、the response.</p><p>　　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

36、 which realizes by servlet. struts-config.xml document disposition controller.　</p><p>　　Service logic, the service logic renewal model's condition, and helps the control application procedure the flow.

37、Speaking of Struts, this is through takes the actual service logic “thin” the packing Action kind to complete.</p><p>　　Model (model) condition, model expression application procedure condition. Service obje

38、ct 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 ActionFo

39、rm bean information.</p><p>　　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

40、 causes Struts is different with other frames (for example Velocity) one of factors.</p><p>　　Just like the Struts controller is (event usually is HTTP post) maps the event kind of servlet. you to expect - t

41、he air-operated controller use configuration files to cause you not to need to carry on to these values the hard code. The time has changed, but method as before.</p><p>　　The Action kind, ActionForm maintai

42、ns 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

43、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, ple

44、ase found its subclass an</p><p>　　ActionServlet (Command) will use perform () the method the parametrization kind to transmit for ActionForm. Still did not have too many repugnant request.getParameter () to

45、 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.</p><p>　　Considered that a Action kind

46、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

47、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. There

48、fore, Struts has provided a servic</p><p>　　5 CSS synopsis</p><p>　　The CSS edition method is the same with HTML, may also be any text editor or the homepage edition software, but also has uses

49、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

50、personnel found out HTML, mainly stresses on the definition content, for instance expressed that a paragraph, indicates the title, but excessively has not</p><p>　　Along with the Internet rapid development,

51、HTML is widely applied, the surfer people hoped certainly that the homepage makes attractive, therefore the HTML typesetting and the contact surface effect's limitation exposes day by day. In order to solve this prob

52、lem, 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

53、the typesetting using</p><p>　　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 c

54、ontent (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 a

55、ccording to its position: In inlays the style (Inline Style), internal cascading style sheet (Internal S</p><p>　　6 HTML function synopsis</p><p>　　Hyper Text Markup the Language hypertext mark

56、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 opera

57、ting 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

58、 Homepage link</p><p>　　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 document

59、s 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 to

60、ol (for example the WORD documents) to transform the HTML documents. 3. by the Web server (or sai</p><p>　　Although the HTML language described the documents structure form, but how can't define the docu

61、ments information to precisely demonstrate and arrange, but is only suggested how the Web browser (for example Mosiac, Netscape and so on) should demonstrate and arrange these information, is decided finally in front of

62、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 </p><p>　　7 Js

63、script language synopsis</p><p>　　JS 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, fo

64、r 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 ti

65、me were too many. Therefore Netscape browser Navigator has joined Javascript, has provided the data confirmatio</p><p>　　The JavaScript official name is “ECMAScript”. This standard by ECMA organization devel

66、opment 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 1

67、996, 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.</p><p>　　Script script uses

68、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 applicatio

69、n 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 t

70、he homepage performance, like animation, </p><p>　　Present's script language is quite many, script language execution generally only with concrete explanation actuator related, so long as therefore on th

71、e 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 i

72、n the time which needs carries out, like this may facilitate you in the CS use. The script may save for the suffix named .cfg do</p><p>　　JSP及其WEB技術</p><p><b>　　. 1 JSP簡介</b></p&g

73、t;<p>　　JSP（JavaServer Pages）是一種基于Java的腳本技術。是由Sun Microsystems公司倡導、許多公司參與一起建立的一種動態(tài)網(wǎng)頁技術標準。JSP技術有點類似ASP技術，它是在傳統(tǒng)的網(wǎng)頁HTML文件(*.htm,*.html)中插入Java程序段(Scriptlet)和JSP標記(tag)，從而形成JSP文件(*.jsp)。用JSP開發(fā)的Web應用是跨平臺的，即能在Linux下運行，也

74、能在其他操作系統(tǒng)上運行。在JSP 的眾多優(yōu)點之中，其中之一是它能將 HTML 編碼從 Web 頁面的業(yè)務邏輯中有效地分離出來。用 JSP 訪問可重用的組件，如 Servlet、JavaBean 和基于 Java 的 Web 應用程序。JSP 還支持在 Web 頁面中直接嵌入 Java 代碼?？捎脙煞N方法訪問 JSP 文件：瀏覽器發(fā)送 JSP 文件請求、發(fā)送至 Servlet 的請求。JSP技術使用Java編程語言編寫類XML的tags和

75、scriptlets，來封裝產(chǎn)生動態(tài)網(wǎng)頁的處理邏輯。網(wǎng)頁還能通過tags和scriptlets訪問存在于服務端的資源的應用邏輯。JSP將網(wǎng)頁邏輯與網(wǎng)頁</p><p>　　Web服務器在遇到訪問JSP網(wǎng)頁的請求時，首先執(zhí)行其中的程序段，然后將執(zhí)行結果連同JSP文件中的HTML代碼一起返回給客戶。插入的Java程序段可以操作數(shù)據(jù)庫、重新定向網(wǎng)頁等，以實現(xiàn)建立動態(tài)網(wǎng)頁所需要的功能。JSP與Java Servlet一樣

76、，是在服務器端執(zhí)行的，通常返回該客戶端的就是一個HTML文本，因此客戶端只要有瀏覽器就能瀏覽。</p><p>　　JSP頁面由HTML代碼和嵌入其中的Java代碼所組成。服務器在頁面被客戶端請求以后對這些Java代碼進行處理，然后將生成的HTML頁面返回給客戶端的瀏覽器。Java Servlet 是JSP的技術基礎，而且大型的Web應用程序的開發(fā)需要Java Servlet和JSP配合才能完成。JSP具備了Ja

77、va技術的簡單易用，完全的面向?qū)ο?，具有平臺無關性且安全可靠，主要面向因特網(wǎng)的所有特點。</p><p>　　2 JSP技術方法 </p><p>　　為了快速方便地進行動態(tài)網(wǎng)站的開發(fā)，JSP在以下幾個方面做了改進，使其成為快速建立跨平臺的動態(tài)網(wǎng)站的首選方案。</p><p>　　2.1 將內(nèi)容的生成和顯示進行分離</p><p>　　用J

78、SP技術，Web頁面開發(fā)人員可以使用HTML或者XML標識來設計和格式化最終頁面，并使用JSP標識或者小腳本來生成頁面上的動態(tài)內(nèi)容。生成內(nèi)容的邏輯被封裝在標識和JavaBeans組件中，并且捆綁在腳本中，所有的腳本在服務器端運行。由于核心邏輯被封裝在標識和JavaBeans中，所以Web管理人員和頁面設計者，能夠編輯和使用JSP頁面，而不影響內(nèi)容的生成。在服務器端，JSP引擎解釋JSP標識和腳本，生成所請求的內(nèi)容，并且將結果以HTML（

79、或者XML）頁面的形式發(fā)送回瀏覽器。這既有助于作者保護自己的代碼，又能保證任何基于HTML的Web瀏覽器的完全可用性。</p><p><b>　　2.2 可重用組件</b></p><p>　　絕大多數(shù)JSP頁面依賴于可重用的、跨平臺的組件（JavaBeans或者Enterprise JavaBeans組件）來執(zhí)行應用程序所要求的復雜的處理。開發(fā)人員能夠共享和交換執(zhí)

80、行普通操作的組件，或者使得這些組件為更多的使用者和客戶團體所使用?；诮M件的方法加速了總體開發(fā)過程，并且使得各種組織在他們現(xiàn)有的技能和優(yōu)化結果的開發(fā)努力中得到平衡。</p><p><b>　　2.3 采用標識</b></p><p>　　Web頁面開發(fā)人員不會都是熟悉腳本語言的編程人員。JSP技術封裝了許多功能，這些功能是在易用的、與JSP相關的XML標識中進行動態(tài)

81、內(nèi)容生成所需要的。標準的JSP標識能夠訪問和實例化JavaBeans組件，設置或者檢索組件屬性，下載Applet，以及執(zhí)行用其他方法更難于編碼和耗時的功能。</p><p><b>　　2.4 適應平臺</b></p><p>　　幾乎所有平臺都支持Java，JSP＋JavaBeans幾乎可以在所有平臺下通行無阻。從一個平臺移植到另外一個平臺，JSP和JavaBean

82、s甚至不用重新編譯，因為Java字節(jié)碼都是標準的與平臺無關的。</p><p><b>　　2.5 數(shù)據(jù)庫連接</b></p><p>　　Java中連接數(shù)據(jù)庫的技術是JDBC，Java程序通過JDBC驅(qū)動程序與數(shù)據(jù)庫相連，執(zhí)行查詢、提取數(shù)據(jù)等操作。Sun公司還開發(fā)了JDBC－ODBC bridge，利用此技術Java程序可以訪問帶有ODBC驅(qū)動程序的數(shù)據(jù)庫，目前大多

83、數(shù)數(shù)據(jù)庫系統(tǒng)都帶有ODBC驅(qū)動程序，所以Java程序能訪問諸如Oracle、Sybase、MS SQL Server和MS Access等數(shù)據(jù)庫。此外，通過開發(fā)標識庫，JSP技術可以進一步擴展。第三方開發(fā)人員和其他人員可以為常用功能創(chuàng)建自己的標識庫。這使得Web頁面開發(fā)人員能夠使用熟悉的工具和如同標識一樣的執(zhí)行特定功能的構件來進行工作。JSP技術很容易整合到多種應用體系結構中，以利用現(xiàn)存的工具和技巧，并且能擴展到支持企業(yè)級的分布式應用中

84、。</p><p>　　3 Eclipse功能簡介</p><p>　　越來越多的Java開發(fā)人員已經(jīng)開始欣賞Eclipse的JDT提供的生產(chǎn)率和質(zhì)量收益。它為Java編輯器提供了語法高亮顯示、格式化、折疊、內(nèi)容輔助、代碼模板等許多功能。它不斷增長的可用重構和代碼生成功能集合允許您在更高的級別上操作代碼，并自動化通常的代碼密集型任務和易錯任務。而且，在開發(fā)完代碼并使用JDT對編寫和執(zhí)行JU

85、nit測試的內(nèi)置支持對代碼進行單元測試之后，可以使用Eclipse的一流Java調(diào)試器調(diào)試在運行時遇到的任何問題。除了JDT之外，Eclipse SDK—最流行的Eclipse.org下載—還包含Plug-in Development Environment(PDE)。PDE使用特定功能擴展了JDT以構建Eclipse插件—基于Eclipse的應用程序的基本構造塊。事實上，使用由Eclipse本身提供的工具能夠超越Java開發(fā)，可擴展現(xiàn)

86、有Eclipse應用程序，或者甚至創(chuàng)建全新的應用程序。</p><p>　　Eclipse由一個小程序?qū)訕嫵?，其中包含許多功能模塊或Eclipse術語中所謂的“插件”。插件是在Eclipse應用程序中提供所有功能的組件。它們通過其API一起協(xié)作來交付最終結果。在Eclipse中，甚至最基礎的功能，比如查找和啟動安裝的插件，都封裝在插件中。為了擴展現(xiàn)有Eclipse功能或在其上進行構建，插件將具體的擴展貢獻給由其他

87、插件暴露的擴展點。通常，插件專注于特定區(qū)域的責任，并通過一個或多個擴展點的方式將其他責任指派給其他插件。例如，一個插件允許您可視地并行比較兩個文件的內(nèi)容，但它不會關心如何讀取這些文件甚至如何解釋這些文件的結構;這是其他插件的工作。比較兩個文件時，該插件首先檢查是否有另一個插件可以解釋這些文件的結構。如果找到一個，它就會向找到的插件詢問有關文件結構的信息，并在比較過程中使用該信息。</p><p>　　可以看到，模

88、塊化架構為Eclipse提供了巨大的靈活性，并提供了一個可以支持原設計者沒有預料到的大量應用程序的平臺。</p><p>　　4 Structs功能簡介</p><p>　　Struts是一個MVC框架（Framework）,用于快速開發(fā)Java Web應用。Struts實現(xiàn)的重點在C(Controller)，包括ActionServlet/RequestProcessor和我們定制的Ac

89、tion,也為V(View)提供了一系列定制標簽（Custom Tag）。Spring是一個輕型容器(light-weight container)，其核心是Bean工廠(Bean Factory)，用以構造我們所需要的M(Model)。在此基礎之上，Spring提供了AOP（Aspect-Oriented Programming, 面向?qū)用娴木幊蹋┑膶崿F(xiàn)，用它來提供非管理環(huán)境下申明方式的事務、安全等服務；對Bean工廠的擴展Appli

90、cationContext更加方便我們實現(xiàn)J2EE的應用；DAO/ORM的實現(xiàn)方便我們進行數(shù)據(jù)庫的開發(fā)；Web MVC和Spring Web提供了Java Web應用的框架或與其他流行的Web框架進行集成。就是說可將兩者一起使用，達到將兩者自身的特點進行互補。</p><p>　　Structs 是一組相互協(xié)作的類、servlet 和 JSP 標記，它們組成一個可重用的 MVC 2 設計。這個定義表示 Strut

91、s 是一個框架，而不是一個庫，但 Struts 也包含了豐富的標記庫和獨立于該框架工作的實用程序類。</p><p>　　Client browser（客戶瀏覽器）,來自客戶瀏覽器的每個 HTTP 請求創(chuàng)建一個事件。Web 容器將用一個 HTTP 響應作出響應。　　</p><p>　　Controller（控制器）,控制器接收來自瀏覽器的請求，并決定將這個請求發(fā)往何處。就 Struts

92、而言，控制器是以 servlet 實現(xiàn)的一個命令設計模式。 struts-config.xml 文件配置控制器?！　?lt;/p><p>　　業(yè)務邏輯,業(yè)務邏輯更新模型的狀態(tài)，并幫助控制應用程序的流程。就 Struts 而言，這是通過作為實際業(yè)務邏輯“瘦”包裝的 Action 類完成的。</p><p>　　Model（模型）的狀態(tài),模型表示應用程序的狀態(tài)。業(yè)務對象更新應用程序的狀態(tài)。Acti

93、onForm bean 在會話級或請求級表示模型的狀態(tài)，而不是在持久級。JSP 文件使用 JSP 標記讀取來自 ActionForm bean 的信息。</p><p>　　View（視圖）,視圖就是一個 JSP 文件。其中沒有流程邏輯，沒有業(yè)務邏輯，也沒有模型信息 -- 只有標記。標記是使 Struts 有別于其他框架（如 Velocity）的因素之一。</p><p>　　Struts

94、 的控制器是將事件（事件通常是 HTTP post）映射到類的一個 servlet.正如您所料 —— 控制器使用配置文件以使您不必對這些值進行硬編碼。時代變了，但方法依舊。</p><p>　　Action類,ActionForm 維護 Web 應用程序的會話狀態(tài)。 ActionForm 是一個抽象類，必須為每個輸入表單模型創(chuàng)建該類的子類。當我說 輸入表單模型 時，是指 ActionForm 表示的是由 HTML

95、 表單設置或更新的一般意義上的數(shù)據(jù)。Action類是業(yè)務邏輯的一個包裝。 Action 類的用途是將 HttpServletRequest 轉(zhuǎn)換為業(yè)務邏輯。要使用 Action ，請創(chuàng)建它的子類并覆蓋 process（） 方法。</p><p>　　ActionServlet （Command） 使用 perform（） 方法將參數(shù)化的類傳遞給 ActionForm .仍然沒有太多討厭的 request.getP

96、arameter（） 調(diào)用。當事件進展到這一步時，輸入表單數(shù)據(jù)（或 HTML 表單數(shù)據(jù)）已被從請求流中提取出來并轉(zhuǎn)移到 ActionForm 類中。</p><p>　　考慮 Action 類的另一種方式是 Adapter 設計模式。 Action 的用途是“將類的接口轉(zhuǎn)換為客戶機所需的另一個接口。Adapter 使類能夠協(xié)同工作，如果沒有 Adapter，則這些類會因為不兼容的接口而無法協(xié)同工作?！?。本例中的客

97、戶機是 ActionServlet ，它對我們的具體業(yè)務類接口一無所知。因此，Struts 提供了它能夠理解的一個業(yè)務接口，即 Action .通過擴展 Action ，我們使得我們的業(yè)務接口與 Struts 業(yè)務接口保持兼容。</p><p><b>　　5 CSS簡介</b></p><p>　　CSS的編輯方法同HTML一樣，也可以是任何文本編輯器或網(wǎng)頁編輯軟件

98、，還有專門用來編輯CSS的軟件。 如果你寫的CSS語句是當成外部樣式表而在HTML文件中調(diào)用，那它的擴展名存成.css就可。當初技術人員想出HTML，主要側(cè)重于定義內(nèi)容，比如 p表示一個段落,h1表示標題，而并沒有過多設計HTML的排版和界面效果。</p><p>　　隨著Internet的迅猛發(fā)展，HTML被廣泛應用，上網(wǎng)的人們當然希望網(wǎng)頁做得漂亮些，因此HTML排版和界面效果的局限性日益暴露出來。為了解決這個

99、問題，人們也走了不少彎路，用了一些不好的方法，比如給HTML增加很多的屬性結果將代碼變得很臃腫，將文本變成圖片，過多利用Table來排版，用空白的圖片表示白色的空間等。直到CSS出現(xiàn)。</p><p>　　CSS可算是網(wǎng)頁設計的一個突破，它解決了網(wǎng)頁界面排版的難題?？梢赃@么說，HTML的Tag主要是定義網(wǎng)頁的內(nèi)容(Content)，而CSS決定這些網(wǎng)頁內(nèi)容如何顯示(Layout)。CSS的英文是Cascading