The solution is to provide higher-level functionality to presentation-page authors at an appropriate level of discourse. The reason tags are considered better than scriptlets is that scriptlets, by definition, are programming, whereas tags can represent high-level concepts.
Hiding JDBC from presentation pages
When integrating JDBC with JSP technology, we want to hide as much of that integration from the presentation author as possible. Where we do expose database concepts, we want to expose them at a suitable level of abstraction. This approach leads to our next example.
In the example in Listing 5, we hide the JDBC integration from the presentation page. (A live version of this page is located on the JavaServer Pages Developers Guide Web site.)
Integrating with JavaBeans components
The examples so far have been fairly simple, but most database operations are going to be more sophisticated than these simple queries and updates. So now that we've covered some basic principles of using JDBC with JSP pages, let's conclude with a slightly more complex, and certainly more common, type of application.
The example for this section will show one way to support visitor-supplied content on a Web site. In other words, we want to allow visitors to read database content associated with a URI and to contribute additional content. Such content is fairly common on modern Web sites. The same basic parts can be used to construct:
Review pages, such as those found on
通用进销存管理系统论文 Links pages
Bulletin boards
Wikiwebs
An only slightly more elaborate version of the JSP components in this example can implement Web pages that seem very different, authored by designers of varying technical backgrounds. All that the pages would appear to have in common is a provision for visitor-contributed content.
Our annotation example uses an HTML form. When using HTML forms with JSP, it is convenient to use a bean whose properties map to the form fields.
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