Some Nucleus components use XML files, rather than Java properties files, for configuration or other initialization purposes. The ATG platform can use XML files just like properties files found in the CONFIGPATH. An XML file might appear at several points in the CONFIGPATH. The ATG platform automatically combines at runtime all the XML files in the CONFIGPATH with the same name into a single composite file, which is then used by the appropriate component. This allows multiple applications or modules to layer on top of each other, forming a single definition file out of multiple definition files.
This section describes the operations and rules that are used to combine two XML files into a result that is a new XML file. XML files are combined one tag at a time; in other words, tags are matched up, and the combination rules are applied to each pair of matched tags. How the tags are matched up will be described later.
XML file combination is controlled with an XML attribute named xml-combine. This attribute is used only in the preprocessing stage of XML file combination. Since the xml-combine attribute is not included in the file that results from the preprocessing combination of the XML files, it does not need to appear in the document type definition (DTD) for the XML files.
