net.sf.saxon.om

Interface NodeInfo

All Superinterfaces:

Item, Location, Locator, PullEvent, Sequence, Source, SourceLocator

All Known Subinterfaces:

FingerprintedNode, MutableNodeInfo, SiblingCountingNode, SteppingNode<N>, VirtualNode

All Known Implementing Classes:

AbsentExtensionElement, AbstractNodeWrapper, AbstractVirtualNode, AnnotationParent, AttributeImpl, AxiomAttributeWrapper, AxiomDocumentNodeWrapper, AxiomElementNodeWrapper, AxiomLeafNodeWrapper, AxiomParentNodeWrapper, CommentImpl, DataElement, DocumentImpl, DocumentInfo, DOM4JNodeWrapper, DOMNodeWrapper, ElementImpl, ExtensionInstruction, FleetingDocumentNode, FleetingElementNode, FleetingNode, FleetingParentNode, JDOM2NodeWrapper, JDOMNodeWrapper, LiteralResultElement, NamespaceNode, NodeImpl, Orphan, ProcInstImpl, SaxonAssign, SaxonDoctype, SaxonEntityRef, SaxonImportQuery, SaxonParam, SaxonPreprocess, SaxonWhile, SchemaElement, SnapshotNode, SpaceStrippedNode, SQLClose, SQLColumn, SQLConnect, SQLDelete, SQLExecute, SQLInsert, SQLQuery, SQLUpdate, StyleElement, TextFragmentValue, TextImpl, TextValueTemplateNode, TinyAttributeImpl, TinyDocumentImpl, TinyElementImpl, TinyNodeImpl, TinyParentNodeImpl, TinyTextImpl, TypeStrippedNode, UnconstructedDocument, UnconstructedElement, UnconstructedParent, UnknownElement, VirtualCopy, VirtualUntypedCopy, WhitespaceTextImpl, XOMDocumentWrapper, XOMNodeWrapper, XSDAlternative, XSDAnnotation, XSDAny, XSDAnyAttribute, XSDAssert, XSDAttribute, XSDAttributeGroup, XSDComplexContent, XSDComplexContentRestriction, XSDComplexType, XSDCompositor, XSDDefaultOpenContent, XSDDocumentation, XSDElement, XSDExtension, XSDFacet, XSDFieldOrSelector, XSDGroup, XSDIdentityConstraint, XSDImport, XSDInclude, XSDList, XSDNotation, XSDOpenContent, XSDOverride, XSDRedefine, XSDSchema, XSDSimpleContent, XSDSimpleContentRestriction, XSDSimpleType, XSDSimpleTypeRestriction, XSDUnion, XSLAccept, XSLAcceptExpose, XSLAccumulator, XSLAccumulatorRule, XSLAnalyzeString, XSLApplyImports, XSLApplyTemplates, XSLAssert, XSLAttribute, XSLAttributeSet, XSLBreak, XSLBreakOrContinue, XSLCallTemplate, XSLCatch, XSLCharacterMap, XSLChoose, XSLComment, XSLContextItem, XSLCopy, XSLCopyOf, XSLDecimalFormat, XSLDocument, XSLElement, XSLEvaluate, XSLExpose, XSLFallback, XSLForEach, XSLForEachGroup, XSLFork, XSLFunction, XSLGeneralIncorporate, XSLGeneralVariable, XSLGlobalContextItem, XSLGlobalParam, XSLGlobalVariable, XSLIf, XSLImport, XSLImportSchema, XSLInclude, XSLIterate, XSLKey, XSLLeafNodeConstructor, XSLLocalParam, XSLLocalVariable, XSLMap, XSLMapEntry, XSLMatchingSubstring, XSLMerge, XSLMergeAction, XSLMergeKey, XSLMergeSource, XSLMessage, XSLMode, XSLModuleRoot, XSLNamespace, XSLNamespaceAlias, XSLNextIteration, XSLNextMatch, XSLNumber, XSLOnCompletion, XSLOnEmpty, XSLOnNonEmpty, XSLOtherwise, XSLOutput, XSLOutputCharacter, XSLOverride, XSLPackage, XSLPerformSort, XSLPreserveSpace, XSLProcessingInstruction, XSLResultDocument, XSLSequence, XSLSort, XSLSortOrMergeKey, XSLStream, XSLStylesheet, XSLTemplate, XSLText, XSLTry, XSLUsePackage, XSLValueOf, XSLWhen, XSLWherePopulated, XSLWithParam

public interface NodeInfo
extends Source, Item, Location

The NodeInfo interface represents a node in Saxon's implementation of the XPath 2.0 data model.

Note that several NodeInfo objects may represent the same node. To test node identity, the method isSameNodeInfo(NodeInfo) should be used. An exception to this rule applies for document nodes, where the correspondence between document nodes and DocumentInfo objects is one to one. NodeInfo objects are never reused: a given NodeInfo object represents the same node for its entire lifetime.

This is the primary interface for accessing trees in Saxon, and it forms part of the public Saxon API. Methods that form part of the public API are (since Saxon 8.4) labelled with a JavaDoc "since" tag: classes and methods that have no such label should not be regarded as stable interfaces.

The interface represented by this class is at a slightly higher level than the abstraction described in the W3C data model specification, in that it includes support for the XPath axes, rather than exposing the lower-level properties (such as "parent" and "children") directly. All navigation within trees, except for a few convenience methods, is done by following the axes using the iterateAxis(byte) method. This allows different implementations of the XPath tree model to implement axis navigation in different ways. Some implementations may choose to use the helper methods provided in class Navigator.

Note that the stability of this interface applies to classes that use the interface, not to classes that implement it. The interface may be extended in future to add new methods.

New implementations of NodeInfo are advised also to implement the methods in interface ExtendedNodeInfo, which will be moved into this interface at some time in the future.

Since:

8.4. Extended with three extra methods, previously in ExtendedNodeInfo, in 9.1. In 9.7, DocumentInfo is no longer defined as a sub-interface; it is replaced with TreeInfo, which contains information about any XML node tree, whether or not it is rooted at a document node.

Author:

Michael H. Kay

Field Summary

Fields

Modifier and Type	Field and Description
static int	ALL_NAMESPACES Copy all in-scope namespaces
static int	IS_DTD_TYPE Bit setting in the returned type annotation indicating a DTD_derived type on an attribute node
static int	IS_NILLED Bit setting for use alongside a type annotation indicating that the is-nilled property is set
static int	LOCAL_NAMESPACES Copy namespaces declared (or undeclared) on this element, but not namespaces inherited from a parent element
static int	NO_NAMESPACES Don't copy any namespace nodes.

Method Summary

Methods

Modifier and Type	Method and Description
AtomicSequence	atomize() Get the typed value.
int	compareOrder(NodeInfo other) Determine the relative position of this node and another node, in document order.
int	comparePosition(NodeInfo other) Determine the relative position of this node and another node, in document order, distinguishing whether the first node is a preceding, following, descendant, ancestor, or the same node as the second.
void	copy(Receiver out, int copyOptions, Location locationId) Copy this node to a given Receiver.
boolean	equals(Object other) The equals() method compares nodes for identity.
void	generateId(FastStringBuffer buffer) Construct a character string that uniquely identifies this node.
String	getAttributeValue(String uri, String local) Get the string value of a given attribute of this node
String	getBaseURI() Get the Base URI for the node, that is, the URI used for resolving a relative URI contained in the node.
int	getColumnNumber() Get column number.
Configuration	getConfiguration() Convenience method to get the Configuration.
NamespaceBinding[]	getDeclaredNamespaces(NamespaceBinding[] buffer) Get all namespace declarations and undeclarations defined on this element.
String	getDisplayName() Get the display name of this node, in the form of a lexical QName.
int	getLineNumber() Get line number.
String	getLocalPart() Get the local part of the name of this node.
int	getNodeKind() Get the kind of node.
NodeInfo	getParent() Get the NodeInfo object representing the parent of this node
String	getPrefix() Get the prefix of the name of the node.
String	getPublicId() Get the Public ID of the entity containing the node.
NodeInfo	getRoot() Get the root node of the tree containing this node
SchemaType	getSchemaType() Get the type annotation of this node, if any.
String	getStringValue() Return the string value of the node as defined in the XPath data model.
String	getSystemId() Get the System ID for the node.
TreeInfo	getTreeInfo() Get information about the tree to which this NodeInfo belongs
String	getURI() Get the URI part of the name of this node.
boolean	hasChildNodes() Determine whether the node has any children.
int	hashCode() The hashCode() method obeys the contract for hashCode(): that is, if two objects are equal (represent the same node) then they must have the same hashCode()
boolean	isId() Determine whether this node has the is-id property
boolean	isIdref() Determine whether this node has the is-idref property
boolean	isNilled() Determine whether the node has the is-nilled property
boolean	isSameNodeInfo(NodeInfo other) Determine whether this is the same node as another node.
AxisIterator	iterateAxis(byte axisNumber) Return an iteration over all the nodes reached by the given axis from this node
AxisIterator	iterateAxis(byte axisNumber, NodeTest nodeTest) Return an iteration over all the nodes reached by the given axis from this node that match a given NodeTest

Methods inherited from interface javax.xml.transform.Source

setSystemId

Methods inherited from interface net.sf.saxon.om.Item

getStringValueCS, head

Methods inherited from interface net.sf.saxon.om.Sequence

iterate

Methods inherited from interface net.sf.saxon.expr.parser.Location

saveLocation

Field Detail

IS_DTD_TYPE

static final int IS_DTD_TYPE

Bit setting in the returned type annotation indicating a DTD_derived type on an attribute node

See Also:

Constant Field Values

IS_NILLED

static final int IS_NILLED

Bit setting for use alongside a type annotation indicating that the is-nilled property is set

See Also:

Constant Field Values

NO_NAMESPACES

static final int NO_NAMESPACES

Don't copy any namespace nodes.

See Also:

Constant Field Values

LOCAL_NAMESPACES

static final int LOCAL_NAMESPACES

Copy namespaces declared (or undeclared) on this element, but not namespaces inherited from a parent element

See Also:

Constant Field Values

ALL_NAMESPACES

static final int ALL_NAMESPACES

Copy all in-scope namespaces

See Also:

Constant Field Values

Method Detail

getTreeInfo

TreeInfo getTreeInfo()

Get information about the tree to which this NodeInfo belongs

Returns:

the TreeInfo

Since:

9.7

getConfiguration

Configuration getConfiguration()

Convenience method to get the Configuration. Always returns the same result as getTreeInfo().getConfiguration()

Returns:

the Configuration to which the tree belongs

Since:

8.4

getNodeKind

int getNodeKind()

Get the kind of node. This will be a value such as Type.ELEMENT or Type.ATTRIBUTE. There are seven kinds of node: documents, elements, attributes, text, comments, processing-instructions, and namespaces.

Returns:

an integer identifying the kind of node. These integer values are the same as those used in the DOM

Since:

8.4

See Also:

Type

isSameNodeInfo

boolean isSameNodeInfo(NodeInfo other)

Determine whether this is the same node as another node.

Note that two different NodeInfo instances can represent the same conceptual node. Therefore the "==" operator should not be used to test node identity. The equals() method should give the same result as isSameNodeInfo(), but since this rule was introduced late it might not apply to all implementations.

Note: a.isSameNodeInfo(b) if and only if generateId(a)==generateId(b).

This method has the same semantics as isSameNode() in DOM Level 3, but works on Saxon NodeInfo objects rather than DOM Node objects.

Parameters:

other - the node to be compared with this node

Returns:

true if this NodeInfo object and the supplied NodeInfo object represent the same node in the tree.

equals

boolean equals(Object other)

The equals() method compares nodes for identity. It is defined to give the same result as isSameNodeInfo().

Overrides:

equals in class Object

Parameters:

other - the node to be compared with this node

Returns:

true if this NodeInfo object and the supplied NodeInfo object represent the same node in the tree.

Since:

8.7 Previously, the effect of the equals() method was not defined. Callers should therefore be aware that third party implementations of the NodeInfo interface may not implement the correct semantics. It is safer to use isSameNodeInfo() for this reason. The equals() method has been defined because it is useful in contexts such as a Java Set or HashMap.

hashCode

int hashCode()

The hashCode() method obeys the contract for hashCode(): that is, if two objects are equal (represent the same node) then they must have the same hashCode()

Overrides:

hashCode in class Object

Since:

8.7 Previously, the effect of the equals() and hashCode() methods was not defined. Callers should therefore be aware that third party implementations of the NodeInfo interface may not implement the correct semantics.

getSystemId

String getSystemId()

Get the System ID for the node. Note this is not the same as the base URI: the base URI can be modified by xml:base, but the system ID cannot. The base URI is used primarily for resolving relative URIs within the content of the document. The system ID is used primarily in conjunction with a line number, for identifying the location of elements within the source XML, in particular when errors are found. For a document node, the System ID represents the value of the document-uri property as defined in the XDM data model.

Specified by:

getSystemId in interface Location

Specified by:

getSystemId in interface Locator

Specified by:

getSystemId in interface Source

Specified by:

getSystemId in interface SourceLocator

Returns:

the System Identifier of the entity in the source document containing the node, or null if not known or not applicable.

Since:

8.4

getPublicId

String getPublicId()

Get the Public ID of the entity containing the node. This method is provided largely so that NodeInfo can act as a Locator or SourceLocator, and many implementations return null.

Specified by:

getPublicId in interface Location

Specified by:

getPublicId in interface Locator

Specified by:

getPublicId in interface SourceLocator

Returns:

the Public Identifier of the entity in the source document containing the node, or null if not known or not applicable

Since:

9.7

getBaseURI

String getBaseURI()

Get the Base URI for the node, that is, the URI used for resolving a relative URI contained in the node. This will be the same as the System ID unless xml:base has been used. Where the node does not have a base URI of its own, the base URI of its parent node is returned.

Returns:

the base URI of the node. This may be null if the base URI is unknown, including the case where the node has no parent.

Since:

8.4

getLineNumber

int getLineNumber()

Get line number. Line numbers are not maintained by default, except for stylesheets and schema documents. Line numbering can be requested using the -l option on the command line, or by setting options on the TransformerFactory or the Configuration before the source document is built.

The granularity of line numbering is normally the element level: for other nodes such as text nodes and attributes, the line number of the parent element will normally be returned.

In the case of a tree constructed by taking input from a SAX parser, the line number will reflect the SAX rules: that is, the line number of an element is the line number where the start tag ends. This may be a little confusing where elements have many attributes spread over multiple lines, or where single attributes (as can easily happen with XSLT 2.0 stylesheets) occupy several lines.

In the case of a tree constructed by a stylesheet or query, the line number may reflect the line in the stylesheet or query that caused the node to be constructed.

The line number can be read from within an XPath expression using the Saxon extension function saxon:line-number()

Specified by:

getLineNumber in interface Location

Specified by:

getLineNumber in interface Locator

Specified by:

getLineNumber in interface SourceLocator

Returns:

the line number of the node in its original source document; or -1 if not available

Since:

8.4

getColumnNumber

int getColumnNumber()

Get column number. Column numbers are not maintained by default. Column numbering can be requested in the same way as line numbering; but a tree implementation can ignore the request.

The granularity of column numbering is normally the element level: for other nodes such as text nodes and attributes, the line number of the parent element will normally be returned.

In the case of a tree constructed by taking input from a SAX parser, the column number will reflect the SAX rules: that is, the column number of an element is the column number where the start tag ends. This may be a little confusing where elements have many attributes spread over multiple lines, or where single attributes (as can easily happen with XSLT 2.0 stylesheets) occupy several lines.

In the case of a tree constructed by a stylesheet or query, the column number may reflect the line in the stylesheet or query that caused the node to be constructed.

The column number can be read from within an XPath expression using the Saxon extension function saxon:column-number()

Specified by:

getColumnNumber in interface Location

Specified by:

getColumnNumber in interface Locator

Specified by:

getColumnNumber in interface SourceLocator

Returns:

the column number of the node in its original source document; or -1 if not available

Since:

9.1

compareOrder

int compareOrder(NodeInfo other)

Determine the relative position of this node and another node, in document order.

The other node must always be in the same tree; the effect of calling this method when the two nodes are in different trees is undefined. To obtain a global ordering of nodes, the application should first compare the result of getDocumentNumber(), and only if the document number is the same should compareOrder() be called.

Parameters:

other - The other node, whose position is to be compared with this node

Returns:

-1 if this node precedes the other node, +1 if it follows the other node, or 0 if they are the same node. (In this case, isSameNode() will always return true, and the two nodes will produce the same result for generateId())

Since:

8.4

comparePosition

int comparePosition(NodeInfo other)

Determine the relative position of this node and another node, in document order, distinguishing whether the first node is a preceding, following, descendant, ancestor, or the same node as the second.

The other node must always be in the same tree; the effect of calling this method when the two nodes are in different trees is undefined. If either node is a namespace or attribute node, the method should throw UnsupportedOperationException.

Parameters:

other - The other node, whose position is to be compared with this node

Returns:

AxisInfo.PRECEDING if this node is on the preceding axis of the other node; AxisInfo.FOLLOWING if it is on the following axis; AxisInfo.ANCESTOR if the first node is an ancestor of the second; AxisInfo.DESCENDANT if the first is a descendant of the second; AxisInfo.SELF if they are the same node.

Throws:

UnsupportedOperationException - if either node is an attribute or namespace

Since:

9.5

getStringValue

String getStringValue()

Return the string value of the node as defined in the XPath data model.

The interpretation of this depends on the type of node. For an element it is the accumulated character content of the element, including descendant elements.

This method returns the string value as if the node were untyped. Unlike the string value accessor in the XPath 2.0 data model, it does not report an error if the element has a complex type, instead it returns the concatenation of the descendant text nodes as it would if the element were untyped.

Specified by:

getStringValue in interface Item

Returns:

the string value of the node

Since:

8.4

See Also:

Item.getStringValueCS()

getLocalPart

String getLocalPart()

Get the local part of the name of this node. This is the name after the ":" if any.

Returns:

the local part of the name. For an unnamed node, returns "". Unlike the DOM interface, this returns the full name in the case of a non-namespaced name.

Since:

8.4

getURI

String getURI()

Get the URI part of the name of this node. This is the URI corresponding to the prefix, or the URI of the default namespace if appropriate.

Returns:

The URI of the namespace of this node. For an unnamed node, or for an element or attribute that is not in a namespace, or for a processing instruction, returns an empty string.

Since:

8.4

getDisplayName

String getDisplayName()

Get the display name of this node, in the form of a lexical QName. For elements and attributes this is [prefix:]localname. For unnamed nodes, it is an empty string.

Returns:

The display name of this node. For a node with no name, returns an empty string.

Since:

8.4

getPrefix

String getPrefix()

Get the prefix of the name of the node. This is defined only for elements and attributes. If the node has no prefix, or for other kinds of node, returns a zero-length string.

Returns:

The prefix of the name of the node.

Since:

8.4

getSchemaType

SchemaType getSchemaType()

Get the type annotation of this node, if any. The type annotation is represented as SchemaType object.

Types derived from a DTD are not reflected in the result of this method.

Returns:

For element and attribute nodes: the type annotation derived from schema validation (defaulting to xs:untyped and xs:untypedAtomic in the absence of schema validation). For comments, text nodes, processing instructions, and namespaces: null. For document nodes, either xs:untyped if the document has not been validated, or xs:anyType if it has.

Since:

9.4

atomize

AtomicSequence atomize()
                       throws XPathException

Get the typed value. This will either be a single AtomicValue or a value whose items are atomic values.

Specified by:

atomize in interface Item

Returns:

the typed value of the node

Throws:

XPathException - if the node has no typed value, for example if it is an element node with element-only content

Since:

8.5. Changed in 9.5 to return the new type AtomicSequence.

getParent

NodeInfo getParent()

Get the NodeInfo object representing the parent of this node

Returns:

the parent of this node; null if this node has no parent

Since:

8.4

iterateAxis

AxisIterator iterateAxis(byte axisNumber)

Return an iteration over all the nodes reached by the given axis from this node

Parameters:

axisNumber - an integer identifying the axis; one of the constants defined in class AxisInfo

Returns:

an AxisIterator that delivers the nodes reached by the axis in turn. The nodes are returned in axis order (document order for a forwards axis, reverse document order for a reverse axis).

Throws:

UnsupportedOperationException - if the namespace axis is requested and this axis is not supported for this implementation.

Since:

8.4

See Also:

AxisInfo

iterateAxis

AxisIterator iterateAxis(byte axisNumber,
                       NodeTest nodeTest)

Return an iteration over all the nodes reached by the given axis from this node that match a given NodeTest

Parameters:

axisNumber - an integer identifying the axis; one of the constants defined in class AxisInfo

nodeTest - A condition to be satisfied by the returned nodes; nodes that do not satisfy this condition are not included in the result

Returns:

an AxisIterator that delivers the nodes reached by the axis in turn. The nodes are returned in axis order (document order for a forwards axis, reverse document order for a reverse axis).

Throws:

UnsupportedOperationException - if the namespace axis is requested and this axis is not supported for this implementation.

Since:

8.4

See Also:

AxisInfo

getAttributeValue

String getAttributeValue(String uri,
                       String local)

Get the string value of a given attribute of this node

Parameters:

uri - the namespace URI of the attribute name. Supply the empty string for an attribute that is in no namespace

local - the local part of the attribute name.

Returns:

the attribute value if it exists, or null if it does not exist. Always returns null if this node is not an element.

Since:

9.4

getRoot

NodeInfo getRoot()

Get the root node of the tree containing this node

Returns:

the NodeInfo representing the top-level ancestor of this node. This will not necessarily be a document node. If this node has no parent, then the method returns this node.

Since:

8.4

hasChildNodes

boolean hasChildNodes()

Determine whether the node has any children.

Note: the result is equivalent to
iterateAxis(Axis.CHILD).next() != null

Returns:

True if the node has one or more children

Since:

8.4

generateId

void generateId(FastStringBuffer buffer)

Construct a character string that uniquely identifies this node. Note: a.isSameNode(b) if and only if generateId(a)==generateId(b)

Parameters:

buffer - a buffer which will be updated to hold a string that uniquely identifies this node, across all documents.

Since:

8.7

Changed in Saxon 8.7 to generate the ID value in a client-supplied buffer

copy

void copy(Receiver out,
        int copyOptions,
        Location locationId)
          throws XPathException

Copy this node to a given Receiver.

This method is primarily for internal use. It should not be considered a stable part of the Saxon API.

Parameters:

out - the Receiver to which the node should be copied. It is the caller's responsibility to ensure that this Receiver is open before the method is called (or that it is self-opening), and that it is closed after use.

copyOptions - a selection of the options defined in CopyOptions

locationId - If non-null, identifies the location of the instruction that requested this copy. If zero, indicates that the location information is not available

Throws:

XPathException - if any downstream error occurs

getDeclaredNamespaces

NamespaceBinding[] getDeclaredNamespaces(NamespaceBinding[] buffer)

Get all namespace declarations and undeclarations defined on this element.

This method is intended primarily for internal use. User applications needing information about the namespace context of a node should use iterateAxis(Axis.NAMESPACE). (However, not all implementations support the namespace axis, whereas all implementations are required to support this method.)

Parameters:

buffer - If this is non-null, and the result array fits in this buffer, then the result may overwrite the contents of this array, to avoid the cost of allocating a new array on the heap.

Returns:

An array of integers representing the namespace declarations and undeclarations present on this element. For a node other than an element, return null. Otherwise, the returned array is a sequence of namespace codes, whose meaning may be interpreted by reference to the name pool. The top half word of each namespace code represents the prefix, the bottom half represents the URI. If the bottom half is zero, then this is a namespace undeclaration rather than a declaration. The XML namespace is never included in the list. If the supplied array is larger than required, then the first unused entry will be set to -1.

For a node other than an element, the method returns null.

isId

boolean isId()

Determine whether this node has the is-id property

Returns:

true if the node is an ID

isIdref

boolean isIdref()

Determine whether this node has the is-idref property

Returns:

true if the node is an IDREF or IDREFS element or attribute

isNilled

boolean isNilled()

Determine whether the node has the is-nilled property

Returns:

true if the node has the is-nilled property