Just Java™ 2

Reading an XML File—SAX Parsers

DOM level 1 was recommended as a standard by the World Wide Web consortium, W3C, in October 1998. In the years since then, a weakness in the DOM approach has become evident. It works fine for small and medium-sized amounts of data, up to, say, hundreds of megabytes. But DOM parsing doesn't work well for very large amounts of data, in the range of gigabytes, which cannot necessarily fit in memory at once. In addition, it can waste a lot of time to process an entire document when you know that all you need is one small element a little way into the file.

To resolve these problems, a second algorithm for XML parsing was invented. It became known as the “Simple API for XML” or “SAX,” and its distinguishing characteristic ...