Web servers in Java

Print ANSI/AIM Code 39 in Java Web servers

Your HTML pages aren t much good if you can t share them with the world Web servers make that possible A Web server is a computer that Connects to the Internet Runs Web server software Responds to requests from Web browsers for Web pages Almost any computer can be a Web server, including your home computer But Web servers generally are computers dedicated to the task You don t need to be an Internet or computer guru to publish your Web pages, but you must find a Web server to serve your pages: If you re building pages for a company Web site, your IT department may have a Web server (Ask your IT guru for the information) If you re starting a new site, you need a host for your pages Finding an inexpensive host is easy 3 shows how to determine your hosting needs and find the perfect provider

The Web is made up of millions of resources, each of them linkable A resource s exact location is the key to linking to it Without an exact address (a Uniform Resource Locator, or URL), you can t use the Address bar in a Web browser to visit a Web page directly URLs are the standard addressing system for resources on the Web Each resource (Web page, site, or individual file) has a unique URL URLs work a lot like your postal address Figure 1-3 identifies the components of a URL

Each URL component helps define the location of a Web page or resource: Protocol: Specifies the protocol the browser follows to request the file The Web page protocol is http:// (the usual start to most URLs) Domain: Points to the general Web site (such as wwwsuncom) where the file resides A domain may host a few files (like a personal Web site) or millions of files (like a corporate site, such as wwwsuncom) Path: Names the sequence of folders through which you must navigate to get to a specific file For example, to get to a file in the evangcentral folder that resides in the developers folder, you use the /developers/evangcentral/ path Filename: Specifies which file in a directory path the browser accesses The URL shown in Figure 1-3 points to the Sun domain and offers a path that leads to a specific file named bioshtml:

Interactions between browsers and servers are made possible by a set of computer-communication instructions: Hypertext Transfer Protocol (HTTP) This protocol defines how browsers should request Web pages and how Web servers should respond to those requests HTTP isn t the only protocol at work on the Internet The Simple Mail Transfer Protocol (SMTP) and Post Office Protocol (POP) make e-mail exchange possible, and the File Transfer Protocol (FTP) allows you to upload, download, move, copy, and delete files and folders across the Internet The good news is that Web browsers and servers do all of the HTTP work for you, so you only have to put your pages on a server or type a Web address into a browser To see how HTTP works, check Webmonkey s article, HTTP Transactions and You :

6 provides the complete details on how you use HTML and URLs to add hyperlinks to your Web pages, and 3 shows how to obtain a URL for your own Web site after you re ready move it to a Web server

The following section removes the mystery from the X This section shows The differences between HTML and XHTML How HTML is written (its syntax) Rules that govern its use Names for important pieces and parts of HTML (and XHTML) markup How to make the best, most correct use of its capabilities