Java Enterprise Best Practices

JAXP

The next API on the list is one which readers should realize is not a parser, or even an API for parsing XML. JAXP is the Java API for XML Processing and is simply an abstraction layer, a thin shim that sits on top of the SAX and DOM APIs. JAXP performs no XML parsing itself, but instead defers this task to the underlying SAX and DOM APIs. The same thing is true for JAXP’s XML transformation processing capabilities.

You should always attempt to use JAXP in a J2EE application. With the release of JAXP 1.1^[12] and support for SAX 2.0 and DOM Level 2, JAXP provides the baseline tool support required for solid Java and XML programming. You’ll be able to migrate applications more easily and change parser and processor vendors at will—with minimal impact on your applications. JAXP also has shown no adverse performance effects, so there is no reason to avoid using JAXP.

Tip

At times, you will decide you need to use vendor-specific extensions to a parser or processor. In these cases, JAXP will obviously not suffice. However, I still recommend using JAXP, except in the specific portions of your code that reference these vendor-specific features.

^[12] JAXP 1.2 offers even more, such as support for XML schema. However, the SAX 2.0 and DOM Level 2 compliance is of much greater import, so I recommend using JAXP 1.1 as a minimum requirement rather than Version 1.2.