Document Object Model

When to Use DOM

On the other hand, if you are dealing with simple data structures and if XML Schema isn't a big part of your plans, then you may find that one of the more object-oriented standards, such as JDOM and dom4j, is better suited for your purpose.

 Because it was designed for use with languages such as C and Perl, DOM does not take advantage of Java's object-oriented features.
看到这里，也许DOM和我想象的那种不同，到底DOM是怎么设计为C,Perl适用的语言的呢？JDom可能就是我以前接触的那个。在看完了全部内容后，我有了大概的概念。JDom之类专门用来处理比较简单的文档，也就是在element之间的内容不是复杂的文档，或者从dom的角度来讲，element中间夹的只是一个text node。而dom就不相同了，他可以处理很复杂的文档，而且dom的健壮性和执行效率都要远远高于jdom。引用原文的一些内容，详细的讲解了如何去选择dom还是jdom。

As you can see, when you are using DOM, even a simple operation such as getting the text from a node can take a bit of programming. So if your programs handle simple data structures, then JDOM, dom4j, or even the 1.4 regular-expression package (java.util.regex) may be more appropriate for your needs.

For full-fledged documents and complex applications, on the other hand, DOM gives you a lot of flexibility. And if you need to use XML Schema, then again DOM is the way to go--for now, at least.

If you process both documents and data in the applications you develop, then DOM may still be your best choice. After all, after you have written the code to examine and process a DOM structure, it is fairly easy to customize it for a specific purpose. So choosing to do everything in DOM means that you'll only have to deal with one set of APIs, rather than two.

In addition, the DOM standard is a codified standard for an in-memory document model. It's powerful and robust, and it has many implementations. That is a significant decision-making factor for many large installations, particularly for large-scale applications that need to minimize costs resulting from API changes.

Finally, even though the text in an address book may not permit bold, italics, colors, and font sizes today, someday you may want to handle these things. Because DOM will handle virtually anything you throw at it, choosing DOM makes it easier to future proof your application.