Strategies for simultaneous peripheral operations on-line using hierarchically structured job information

Spooling strategies are described for producing job information that conforms to a hierarchical structure, and then storing the job information in a spool storage. The job information is then retrieved from the spool storage and consumed. The structured job information includes a multi-level hierarchy of nodes, including a job level that represents the entire job, a document level that represents a document to be processed within the job; a rendition level that represents a rendition of the document to be processed; and a page level that represents a page associated with the rendition. The hierarchical structure can also include resource nodes and metadata nodes associated with any level of the hierarchy, respectively representing resources and metadata. The hierarchy can optionally be composed using one or more selection and sequence parts. Program logic implements the production and consumption of the job information by providing a collection of logic modules for selectively adding and retrieving elements to the hierarchically structure. The program logic also provides logic for enumerating the contents of the job information and for signaling the occurrence of various events associated with the processing of the job information.