Part III: Making It Cool with Advanced Features in Java

Painting Denso QR Bar Code in Java Part III: Making It Cool with Advanced Features

To help you better appreciate how a dynamic Web site works, this section takes a closer look at how a blog works The following steps are designed to give you a tour of the front end, which visitors to a blog see, as well as the back end, which the blogger uses to add content to the database This is a common way that many dynamic Web sites are built: 1 Point your browser to wwwmobilewebdesignblogcom 2 On the home page, you see the first part of the most recent post in the database for this site, as shown in Figure 13-1

Figure 13-1: My Mobile Web Design blog s front page displays the first couple of paragraphs for each post in the database Each headline links to a complete post

3 Click the headline on the front page and the browser displays a new page, created dynamically, which displays the entire post You can also click the link at the bottom of the text that reads Click to Continue Reading, as you can see in Figure 13-1 When you view pages like this, keep in mind that there s really only one copy of the article stored in the database When you click a linked headline, the PHP technology pulls the complete post from the database, inserts it into the same template, and displays it as a new page in the Web browser in place of the page that displayed the link you clicked Another advantage of blogging programs is they can set these links for you automatically Thus, you simply enter a story into the system and the program automatically turns the headline into a link and inserts the text Click here to continue reading with a link to the full version of the story

Behind the scenes of this same blog is a set of administrative pages, also generated dynamically (See Figure 13-2) As the author of the blog, I use the administrative pages to enter headlines, articles, images, and even specify how much of the story I want to appear on the front page before the link to the full story The administrative tools (or in WordPress terms, the Dashboard) is the interface I use to enter information into the database That information is then displayed on the front-end page, according to the settings in the blog software

Figure 13-2: To add posts to my Mobile Web Design blog, I use backend features to enter headlines, images, and text into the database

When you create dynamic Web sites, you need one program to create the data source (which is usually a database or an XML file) and another program or Web technology to connect the data source to your Web pages In the sections that follow, you find a description of the five technologies that Dreamweaver supports for creating dynamic sites: PHP, JSP, ASP, ASPNET, and ColdFusion There are many types of data sources The most powerful option is a highend database, such as MySQL, but you can also use simpler database programs, including Microsoft Access XML files, which are specially designed text files, can also be used a data sources WordPress, like many blogs, combines a MySQL database with PHP

One of the most complicated aspects of how dynamic sites work is how you set up the connection between the Web site that your visitor s see and the data source that contains all your articles, images, and other content Essentially, this puzzle has three pieces: the data source, the Web server, and the Web technology that makes the two work together There are many ways to set up this connection You can create a very simple script using a programming language like Java, or you can create a highly complex combination of programs that work in tandem to complete many tasks simultaneously For example, displaying XML data on a Web page requires a relatively simple program A far more complex setup collects information about a user s shopping habits and then compares that with data from multiple sources before generating a Web page specific to the visitor Depending on the complexity of the dynamic site and the data source, you may also need an application server, as well as a Web server and a database Dreamweaver supports five popular technologies that can be used to connect a data source to a Web site (described in detail in the following sections): Active Server Pages (ASP) ASPNET JavaServer Pages (JSP) Adobe ColdFusion PHP (which stands for PHP Hypertext Preprocessor a recursive acronym, for you wordsmiths) Although all five vary in technical specifications and requirements, they offer similar functionality: All provide the capability to generate Web pages dynamically All can be used to connect your Web site to a database or other data source Using server-side code, all can display information from a database and create XHTML based on certain criteria such as the actions or data entered by a visitor to your site Although I don t recommend any one of these options over another, one consideration is important: Make sure that your choice works on your Web server Not all Web servers are set up to handle each and every one of these technologies The following descriptions are designed to help you make a more informed decision about which option best serves your needs