Validating XML Documents

Abstract

In Chapters 2, 3, and 4, you learned how to read and write XML documents, though we always assumed that the XML structure (tag names, attribute names, nesting, and so on) contained in the source XML document was correct. However, in many real-world cases this assumption may not be true. For example, a purchase order application might be accepting orders from various customers in XML format. What is the guarantee that each submitted order adheres to the agreed-on XML structure? What if somebody deviates from the agreed-on structure? This is where XML schemas come into the picture.