[jdom-interest] getElementById

Laurent Bihanic laurent.bihanic at atosorigin.com
Wed Jan 30 08:50:21 PST 2002


Hi,

To support this feature, JDOM needs to know that a given attribute is an ID. 
The latest JDOM (in CVS) supports attribute types. So if you have a DTD, you 
can declare some attributes to be IDs and JDOM will save this information.

Now accessing an element by its ID is just a matter of building a look-up 
table when parsing the document. This feature is not included in the default 
JDOM Document and Element objects because it would consume extra CPU and 
memory every time a document is parsed or a new Element is added to a Document.

So, the best way to support this feature is to subclass Document and Element 
and create a new JDOMFactory implementation to return these subclasses. That 
way, only people actually needing the look-up feature will pay the price (CPU 
+ memory) for it.

A example of such a factory will shortly be available in the contrib package.
If you are interested in this sample code, just drop me a mail and I'll send 
you the code.

Laurent


Eugene Karpov wrote:

> It is very useful method in DOM Document: Document.getElementById. Why you 
> did not implement it?
> 





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