net.sf.saxon.om

Interface Summary
Interface	Description
AtomicSequence	Interface representing a sequence of atomic values.
AtomizedValueIterator	Interface implemented by an iterator that can deliver atomized results.
AttributeCollection	AttributeCollection represents the collection of attributes available on a particular element node.
DocumentInfo	This interface represents a document node as defined in the XPath 2.0 data model.
FingerprintedNode	This is a marker interface used to identify nodes that contain a namepool fingerprint.
FocusIterator	An iterator that maintains the values of position() and current(), typically implemented as a wrapper over an iterator which does not maintain these values itself.
FunctionItem	XDM 3.0 introduces a third kind of item, beyond nodes and atomic values: the function item.
GroundedValue	A value that exists in memory and that can be directly addressed
IdentityComparable	The IdentityComparable class provides a way to compare class objects for strong equality.
Item	An Item is an object that can occur as a member of a sequence.
MutableDocumentInfo	Interface representing the document node of a mutable document
MutableNodeInfo	An extension of the NodeInfo interface defining a node that can be updated.
NamespaceResolver	Abstract class that supports lookup of a lexical QName to get the expanded QName.
NodeInfo	The NodeInfo interface represents a node in Saxon's implementation of the XPath 2.0 data model.
NodeName	This interface represents a node name.
NotationSet	A set of declared notations (in the sense of XSD xs:notation)
Sequence	This interface represents an XDM Value, that is, a sequence of items.
SequenceIterator	A SequenceIterator is used to iterate over any XPath 2 sequence (of values or nodes).
SpaceStrippingRule	Interface for deciding whether a particular element is to have whitespace text nodes stripped

Class Summary
Class	Description
AbsolutePath	Represents the path from the root of an XDM tree to a specific node, as a sequence of (name, position) pairs
AbsolutePath.PathElement	Inner class representing one step in the path
AbstractItem	Abstract superclass for items
AllElementsSpaceStrippingRule	A whitespace stripping rule that strips all elements unless xml:space indicates that whitespace should be preserved.
AtomicArray	A sequence of atomic values, implemented using an underlying arrayList.
AxisInfo	An axis, that is a direction of navigation in the document structure.
Chain	A chain is an implementation of Sequence that represents the concatenation of a number of subsequences.
CodedName	An implementation of NodeName that encapsulates an integer namecode and a reference to the NamePool from which it was allocated.
CopyOptions	Non-instantiable class to define options for the `NodeInfo.copy(net.sf.saxon.event.Receiver, int, int)` method
DocumentPool	An object representing the collection of documents handled during a single transformation.
DocumentURI	This class encapsulates a string used as the value of the document-uri() property of a document, together with a normalized representation of the string used for equality comparisons.
EmptyAtomicSequence	An implementation of AtomicSequence that contains no items.
FingerprintedQName	A QName triple (prefix, URI, local) with the additional ability to hold an integer fingerprint.
FocusTrackingIterator	An iterator that maintains the values of position() and current(), as a wrapper over an iterator which does not maintain these values itself.
InscopeNamespaceResolver	A NamespaceResolver that resolves namespace prefixes by reference to a node in a document for which those namespaces are in-scope.
LazySequence	A sequence that wraps an iterator, without being materialized.
MemoSequence	A Sequence implementation that represents a lazy evaluation of a supplied iterator
NameChecker	The NameChecker performs validation and analysis of XML names.
NameOfNode	An implementation of NodeName that gets the name of an existing NodeInfo object.
NamePool	A NamePool holds a collection of expanded names, each containing a namespace URI, a namespace prefix, and a local name.
NamespaceBinding	Represents the binding of a prefix to a URI.
NoElementsSpaceStrippingRule	A whitespace stripping rule that strips all elements unless xml:space indicates that whitespace should be preserved.
NoNamespaceName	An implementation of NodeName for the common case of a name in no namespace
One<T extends Item>	A sequence containing exactly one item.
OneOrMore<T extends Item>	A value that is a sequence containing one or more items.
SelectedElementsSpaceStrippingRule	A whitespace stripping rule that strips elected elements unless xml:space indicates that whitespace should be preserved.
SequenceTool	Utility class for manipulating sequences.
StandardNames	Well-known names used in XSLT processing.
StructuredQName	This class provides an economical representation of a QName triple (prefix, URI, and localname).
StylesheetSpaceStrippingRule	A whitespace stripping rule that strips whitespace according to the rules defined for XSLT stylesheets
TreeModel	A TreeModel represents an implementation of the Saxon NodeInfo interface, which itself is essentially an implementation of the XDM model defined in W3C specifications (except that Saxon's NodeInfo understands the 13 XPath axes, rather than merely supporting parent and child properties).
ZeroOrMore<T extends Item>	A value that is a sequence containing one or more items.
ZeroOrOne<T extends Item>	A value that is a sequence containing zero or one items.

Exception Summary
Exception	Description
NamePool.NamePoolLimitException	Uncaught Exception raised when some limit in the design of the name pool is exceeded
NamespaceException	A NamespaceException represents an error condition whereby a QName (for example a variable name or template name) uses a namespace prefix that is not declared
QNameException	A QNameException represents an error condition whereby a QName (for example a variable name or template name) is malformed

Package net.sf.saxon.om Description

This package defines the interface to the Saxon tree structure. This structure is used to represent both the source document and the stylesheet. Essentially, this class represents Saxon's realization of the XPath data model.

The classes in the package are rather a miscellany. What they have in common is that they describe the way the Saxon tree structure is accessed, in a way that it independent of the two tree implementations (in packages net.sf.saxon.tree and net.sf.saxon.tinytree).

Broadly speaking, the classes fall into four categories:

Interface classes: DocumentInfo, NodeInfo, Item, ValueRepresentation. These describe the interface offered by the object model to the rest of the system, including the application.
Iterator classes: SequenceIterator, AxisIterator, ArrayIterator, EmptyIterator, SingletonIterator, and others. These classes provide mechanisms for iterating over sequences. The most general, and the one which applications are most likely to use, is the SequenceIterator interface itself. AxisIterator is a specialization of this interface whose main difference is that it cannot throw exceptions. The other classes are implementations of SequenceIterator for use in particular circumstances.

Shared implementation classes: DocumentPool, NamePool, Navigator, XMLChar. These contain functionality that is shared between the various tree implementations. (However, there is also some shared functionality in the net.sf.saxon.tree package). These classes are not generally needed by applications, with the exception of NamePool, which complex applications may need to manipulate.

Information classes: Axis, NamespaceConstant. These contain constants.

Michael H. Kay
Saxonica Limited
9 February 2005