JSP Tag Library Introduction (1) turn

JS Author: Casey Kochmer/Translator: Liao
Date: February 27, 2001


<!-not quite familiar with the powerful features of the Java Servlet page? Well, come with me. One of the most compelling tools of JSP: the JSP tag Library. -->

The author uses JSP and ASP to engage in programming work for a long time, I increasingly feel that in these two server-side programming solutions, JSP functions more powerful than the ASP. Why should I choose my JSP as my main server-side application authoring tool? Of course, JSP has fascinating features and features, but the tag library is one of the most important incentives for me to make this decision.

Why do you say that? There are two reasons: maintenance and development speed. The server-side scripting language is actually like a furnace for developing the Internet. On a server page, you can easily mix a variety of different scripting methods and objects. This kind of page is the concrete that constructs the web. It is this mixture of "materials" that gives the server-side script powerful information processing capabilities. It enables server-side programming designers to develop dynamic, flexible Web pages. But, on the other hand, the free mix of scripts is difficult to maintain, especially as the size of the project grows. We will have to allow experienced programmers to build and maintain the final product, and the result is to make these programmers a common web designer. Server-side applications weaken in both the final graphic design and implementation. To make things worse, because these pages are complex to code, the speed of development is correspondingly reduced. Finally, many medium-scale or large server-side Web applications are launched late and cost is beyond control. In addition, after implementing these applications, many vendors have to look for qualified programmers to maintain this mess like spaghetti code.

None of us would like to see such a result, so in order to overcome this problem, ASP introduced COM object technology, while JSP provides Java as a countermeasure. These solutions are built on a centralized, reusable code base mechanism. However, they are too difficult to use and have a lot of time to spend. Also, these solutions do not reduce the temptation to create messy code, and as a result, we can only organize large, internally structured development teams to use these technologies. This means that although we now have the above methods of building large projects, medium-sized projects are not being patronized by these technologies.

Realistically, a medium-sized project is the principal part of a Web application. Therefore, many projects have to face the situation that their development and maintenance environment cannot meet their needs.

Luckily, JSP provides us with the best solution to this problem, and the tag library (tag libraries) provides a simple way to build reusable blocks of code. But unlike COM and Java EE, you don't have to have any extra skills to build a tag library: If you write a JSP page, you create a tag library. Finally, the tag library also improves the maintainability of Web applications. This improvement in maintainability is demonstrated by the ease with which xml-based customizable interfaces can be implemented on JSP pages. As it turns out, web designers can build JSP Web applications without having to know what JSP is all about. As a result, web development becomes a very productive team development task. JSP programmers can build custom tags and back-end code modules, while web designers can use custom tags and focus on the web design itself. The tag library solves the problem of code clutter and is clean and beautiful (in fact, XML is the essence of solving these problems, but the tag library still plays a very important role).