1、东华理工大学毕业设计 外文翻译 1 JSP Technology（ 外文原文 ） JSP (JavaServer Pages) is a kind of based on Java script technology. In many of the advantages of JSP, one of which is it can the HTML code from Web pages in the business logic of the effectively separated. With JSP visit reusable components, such as Servlet,
2、 JavaBean and based on Java Web applications. JSP also support in Web page direct embedded Java code. The two methods can visit JSP files: browser to send files request, sent to the JSP Servlet request. JavaServer Pages technology is an extension of the Java Servlet technology. Servlets are platform
3、-independent, server-side modules that fit seamlessly into a Web server framework and can be used to extend the capabilities of a Web server with minimal overhead, maintenance, and support. Unlike other scripting languages, servlets involve no platform-specific consideration or modifications； they a
4、re application components that are downloaded, on demand, to the part of the system that needs them. Together, JSP technology and servlets provide an attractive alternative to other types of dynamic Web scripting/programming by offering: platform independence； enhanced performance； separation of log
5、ic from display； ease of administration； extensibility into the enterprise； and, most importantly, ease of use. The Unified Expression Language (EL) The simple EL included in JSP 2.0 technology offers many advantages to the page author. Using simple expressions, page authors can easily access extern
6、al data objects from their pages. The JSP technology container evaluates and resolves these expressions as it encounters them. It then immediately returns a response because the JSP request-processing model has only one phase, the render phase. However, because the request-processing model does not
7、support a postback, all JSP expressions are read-only. Unlike JSP technology, JavaServer Faces technology supports a multiphase life cycle. When a user enters values into the JavaServer Faces UI components and submits the page, those values are converted, validated, and propagated to server-side dat
8、a objects, after which component events are processed. In order to perform all these tasks in an orderly fashion, the JavaServer Faces life cycle is split into separate phases. Therefore, JavaServer Faces technology evaluates expressions at different phases of the life cycle rather than immediately,
9、 as JSP technology would do. 东华理工大学毕业设计 外文翻译 2 JSP technology - friend or foe? Presentation technology was designed to transform plain ol raw Web content into content wrapped in an attractive presentation layer. JavaServer Pages (JSP) technology, Suns presentation model and part of the J2EE platform
10、, has received significant attention. There are both advantages and disadvantages to using JSP technology, and Web developers should be aware of the good and the bad - and know that they dont have to be limited to this single technology. In fact, these days a number of presentation technologies are
11、available. This article begins by defining the problems presentation technologies were designed to solve. It then examines the specific strengths and weaknesses of the JSP model. Finally, it introduces some viable alternatives to Suns presentation technology. A bit of historyBefore diving into an ex
12、planation of presentation technology, its helpful to fill in some details on the situation that led to the birth of the technology. Just 10 short years ago, the term thin client was a novelty. We still lived in a world of desktop applications, powered by wimpy 286 microprocessors with 14-inch monito
13、rs that we squinted at. Boy, have times changed! Now my desktop does nothing but power a Web browser, while servers from Sun, IBM, HP, Compaq, and the rest churn out computations, business logic, and content. And that little monitor? Replaced by flat-screen, plasma, whopping 21- and 25-inch beauties
14、. Why? So we can see the intricate and complex HTML displays that serve as a front-end to these powerful applications. No longer does a clunky interface suffice； now we expect flashy graphics, moving images, color-coordinated presentations that would look good in any room in the house, and speedy re
15、ndering to boot. The premiseToday, a decade beyond those fledgling Windows applications, we are still dealing with this huge shift in the presentation paradigm. The woeful Visual Basic and C programmers who remain now find themselves working either on back-end systems or Windows-only applications, o
16、r they have added a Web-capable language such as the Java language to their toolbox. An application that doesnt support at least three of four ML-isms - such as HTML, XML, and WML - is considered shabby, if not an outright failure. And, of course, that means we all care very deeply about the ability
17、 to easily develop a Web presentation layer.As it turns out, using the new Internet, and all the languages we have at our disposal - Java, C, Perl, Pascal, and Ada, among others - hasnt been as easy as we might have hoped. A number of issues creep up when it comes to taking the programming languages
18、 everyone used for back-end systems and leveraging them to generate markup 东华理工大学毕业设计 外文翻译 3 language suitable for a client. With the arrival of more options on the browser (DHTML and JavaScript coding, for example), the increase in graphic artist talent in the Web domain, and tools that could creat
19、e complex interfaces using standard HTML, the demand for fancy user interfaces has grown faster than our ability to develop these front ends to our applications. And this has given rise to presentation technology.Presentation technology was designed to perform a single task: convert content, namely
20、data without display details, into presentation - meaning the various user interfaces you see on your phone, PalmPilot, or Web browser. What are the problems that these presentation technologies claimed to solve? Lets take a look. Segregation vs. integration The primary purpose of presentation techn
21、ology is to allow a separation between content and presentation. In other words, business logic units (presumably in some programming language like C or Java) dont have to generate data in a presentation-specific manner. Data, or content, is returned raw, without formatting. The presentation technol
22、ogy then applies formatting, or presentation, to this content. The result is an amalgam of data surrounded by and intertwined with graphics, formatting, colors, and logos.Look at the examples in Listing 1 and Listing 2 to see at a glance the difference between raw content and content combined with p
23、resentation technology.Listing 1 shows raw content, with nothing but data, that could be used in a variety of ways. class=displaycodeRussell Crowe Tom Hanks Meg Ryan Mary Stuart Masterson Alec Baldwin Ashley Judd Keanu Reeves Listing 2, which is much more complex than the one above, shows the same data wrapped in presentation technology and ready for display in an HTML-capable browser. class=displaycode Search Results: Actors
