The document type declaration (DTD) of an XML message is represented by a syntax element with field type XML.DocTypeDecl, and its children. These comprise the DOCTYPE construct.

Only internal (inline) DTD subsets are represented in the syntax element tree. An inline DTD is a DTD that is declared within the XML document itself. It can be a complete DTD definition, or it can extend the definition in an external DTD.

External DTD subsets (identified by the SystemID or PublicId elements described later in this section) can be referenced in the message, but those referenced are not resolved by the integration node.

The following field type constants can be used to reference the various parts of a DTD in the message tree:

XML DTD example shows an example of an XML DTD.

See XML document type declaration for more information about handling an inline DTD.