I need to generate the xml file from database(Strings).Which is the best open source API from performance ,scalability and usability point of view.In xml I need to put attributes,and Schema statements in generated file.
Personally, I just write that kind of XML document with straight println and other plain old Java statements, it all depends with what you are comfortable with.
There very rarely is a single "best" of anything. What's more, what "best" is would depend on your circumstances, about which we know nothing. I might choose XOM for this, unless it's a really simple format, in which case Bill's suggestion is a good one.