XML definition files

These standard XML definition files are supported:

  • Document Type Definition (.dtd)
  • DTD-containing-XML (.xml )
  • XML Schema Definition (.xsd)

XML files reside in $HCISITEDIR/formats/.

These files, which are text documents, use a syntax consisting of programmatic statements and key words that relate to the structure of an XML message. These files provide the XML standard means against which XML messages are checked for validity. Because they are text, they may be written using any text editor.

The schema files must be well-formed and valid according to their standard specifications before they are compiled in the system.

DTD and DTD-containing-XML

DTD is the oldest and most primitive schema format for XML. It has no support for features such as namespaces.

DTD-containing-XML are XML message documents that also contain DTD information.

Schema

XSD is a later definition language than DTD and is more powerful than DTD in describing XML languages.

See http://www.w3.org/TR/xmlschema-0/

Most of the grammar and semantics described in the XML Schema specification is supported, with these exceptions:

  • With the XML Schema definition, you can constrain the values in an element or attribute through user-defined data types. It provides a list of primitive types with facets that you can use to limit the set of acceptable values. Some of these primitive types are supported, but for more complex types the values must be within the constraints. Any type that does not convert to a system supported type is left as a string.
  • An XML Schema document can internally contain references to other external DTD/Schema/DTD-containing-XMLs that are required for root file processing. For example, using the import or include tag. It is your responsibility to edit external references so that they remain within these specified confines. You must also maintain those external resources and assure that they exist within the server.