When will we use DOM and SAX?

[ssiva kumar]

Hi,
What are the differents between DOM and SAX...

DOM-->Tree Structure Data Dealing(What is meaning for tree)
SAX-->Event Data Dealing..(What is event)

But i have doubt for all xml is a tree structur view why we use sax some time and dom also some... plz explain when will we use sax and dom....

[Ulf Dittmer]

DOM builds the complete XML tree in memory, which takes time and uses up a bunch of memory.

SAX, on the other hand, does not build any in-memory stuctures, and allows the developer to do something just with those nodes that the application is interested.

You'd use SAX if you don't need the XML tree (say, for later modification and saving), and want to save resources (time, memory). Drawback is (obviously) that you don't have the XML tree, so you can't easily determine, e.g., the parent or sibling of a given node.