毕 业 设 计（论文） 外 文 文 献 翻 译
文献、资料中文题目： Web信息系统 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
With the popularity of the Inter NET applications, a variety of Web Information System Has become a pressing issue. Establish the essence of Web information systems Development of a Web repository (database as the core of a variety of Web letter Information storage) as the core Web applications. Currently, the Web repositorydevelopment technology
Operation of a wide range of different characteristics. Various periods at all levels, a variety of purposes Technology co-exist, dizzying mirror chaos, it is difficult to choose. More popular Java of Ser vet Web repository development program a more practical Of choice.
Servlet is running the applet on the Web server, can be completed Xu Multi-client Applet can not complete the work, which runs on the server and clients No end, do not download do not by the client security restrictions, the running speed Greatly increased And Applet running in a browser and extend the browser's ability similar Like, Serv the let run in the Web server to enable Java Serv the let engine And expand the capacity of the server. Therefore, we can say Serv the let is run in Applet on a Web server, Serv the let Jav a Ser vlet API And Jav a program of classes and packages.
1 Servlet access model
Serv the let, there are three access models: (1) an access model
1 browser to Web server to issue a retrieval request.
2 the Web server after receipt of the request, the request forwarded to the Servle tengine.
3 Serlet engine to perform the requested the Ser vlet and directly through JDBC
4Servlet throughJDBC toretrieve search results to generate the html page and Page back to the Web server. 5 the Web server the page is sent back to the browser.
(2)The second access model 1 browser to Web server to issue a retrieval request. 2 the Web server receives the request after the request forwarded to the of Ser v the letengine. 3 Serv let engine to perform the request the the Ser vlet and retrieve sent Ja, vabean access to the data. 4data access the Ja vabean searchable database through JDBC information And from the search results stored in itself. 5Servlet remove search results from the data access Javabean generate Html page and Ht ml of page back to the w eb server. 6 the Web server the page is sent back to the browser.
2
(3) The third access model
1 A browser issue a retrieval request to the Web server.
2 Web server receives the request after the request forwarded to the of Ser v the let engine.
Of Ser vlet engine to perform the requested Servlet directly through JDBC inspection
3 The cable database and search results are stored in the result is stored the Jav abean into.Javabean,
4. Ser v the let from the results are stored to remove the search results and JSP files to format the output page.
2 Servlet functionality and life cycle
2.1 Servlet functions
(1) Create and return dynamic Web pages based on customer requests. (2) create can be embedded into existing HTML pages as part of HTML Page (HT fragment) of the ML. (3) and other server resources (including databases and applications based on the Jav a Program) to communicate. (4) to handle multiple client connections, receiving the input of more than one client, and The results broadcast to multiple clients. For example, Ser vlet is a multi-participant Game server. (5) of MIM E type filter information on the special handling, such as image Conversion and server-side include (SSI). (6) custom processing available to all servers in the standard routine.
2.2Servlet lifecycle
Servlet life cycle begins with it into the Web And end in the termination or re-loaded Serv the let.
server's
memory
(1) load.
Load the servlet at the following times:
1. If you have configured automatic load option, and then start the Web server automatically loaded
2. After the start of the Web server, the client Serv the let issued for the first time, please
Demand.
3. Reload Serv the let.
Loaded Servlet, Web servers to create a servlet instance, and Servlet's init () method is called. Servlet initialization parameters in the initialization phase, The number is passed to the Servlet configuration object. (2) terminate When the Web server no longer needs the servlet, or reload Servlet A new instance of the server calls Serv the let's destroy () method, remove it from the Memory deleted.
毕业论文外文文献翻译Web信息系统
