XML by Example

Figure 3.2: The tree for the address

Benefits of the DTD

The main benefits of using a DTD are

• The XML processor enforces the structure, as defined in the DTD.

• The application accesses the document structure, such as to populate

an element list.

• The DTD gives hints to the XML processor—that is, it helps separate

indenting from content.

• The DTD can declare default or fixed values for attributes. This might

result in a smaller document.

Validating the Document

You can validate documents with an XML processor. I invite you to down-

load XML for Java from the IBM Web site at www.alphaworks.ibm.com.

There are other XML processors, but I will use the IBM ...