Package net.sf.saxon.pull

This package provides classes that interface Saxon to an XML parser that supplies data in the form of a stream of events.

See: Description

Interface Summary

Interface	Description
PullProvider	PullProvider is Saxon's pull-based interface for reading XML documents and XDM sequences.

Class Summary

Class	Description
NamespaceContextImpl	This class bridges between the JAXP 1.3 NamespaceContext interface and Saxon's equivalent NamespaceResolver interface.
PullConsumer	A PullConsumer consumes all the events supplied by a PullProvider, doing nothing with them.
PullFilter	PullFilter is a pass-through filter class that links one PullProvider to another PullProvider in a pipeline.
PullPushCopier	This class copies a document by using the pull interface to read the input document, and the push interface to write the output document.
PullPushTee	PullPushTee is a pass-through filter class that links one PullProvider to another PullProvider in a pipeline, copying all events that are read into a push pipeline, supplied in the form of a Receiver.
PullSource	A PullSource is a JAXP Source that encapsulates a PullProvider - that is, an object that supplies an XML document as a sequence of events that are read under the control of the recipient.
StaxBridge	This class implements the Saxon PullProvider API on top of a standard StAX parser (or any other StAX XMLStreamReader implementation)
UnparsedEntity	This class is used to represent unparsed entities in the PullProvider interface

Package net.sf.saxon.pull Description

This package provides classes that interface Saxon to an XML parser that supplies data in the form of a stream of events. It provides an interface, PullProvider, that is an abstraction over the pull parser interfaces provided on Java and .NET, and that can in principle be implemented by other data sources to deliver input documents as if they came from a parser.

This package is almost obsolete. Pull-mode processing of queries, when required at all, is generally done using the classes in the net.sf.saxon.evpull package, which deliver a stream of events as objects, rather than as simple integers (analogous to the two styles of pull processing interface in StAX).

The API, defined in class PullProvider, is loosely modelled on the StAX XMLReader API. It is not identical, because it is designed as an intimate and efficient interface that integrates with Saxon concepts such as the SequenceIterator and the NamePool. A class StaxBridge is available that provides the PullProvider interface on top of a StAX pull parser. In the .NET build, a similar class DotNetPullProvider interfaces Saxon to the Microsoft XmlTextReader.

A source of data delivered by a PullProvider may be presented either as a PullSource or as a StaxSource. Both these are accepted by any Saxon interface that allows a JAXP Source object to be supplied.

Additional implementations of PullProvider are available in Saxon-PE and Saxon-EE, specifically, implementations that deliver data by walking a Saxon tree structure (represented by class NodeInfo), and implementations that allow queries to be evaluated in pull mode, with lazy construction of temporary document and element nodes.

Some examples of application code using the pull interface with Saxon are provided in the PullExamples.java file in the samples directory.

Michael H. Kay
Saxonica Limited
10 June 2009