org.exist.dom
Class VirtualNodeSet

java.lang.Object
  org.exist.xquery.value.AbstractSequence
      org.exist.dom.AbstractNodeSet
          org.exist.dom.VirtualNodeSet

All Implemented Interfaces:

NodeSet, Sequence, NodeList

public class VirtualNodeSet
extends AbstractNodeSet

This node set is called virtual because it is just a placeholder for the set of relevant nodes. For XPath expressions like //* or //node(), it would be totally unefficient to actually retrieve all descendant nodes. In many cases, the expression can be resolved at a later point in time without retrieving the whole node set. VirtualNodeSet basically provides method getFirstParent to retrieve the first matching descendant of its context according to the primary type axis. Class LocationStep will always return an instance of VirtualNodeSet if it finds something like descendant::* etc..

Author:

Wolfgang Meier, Timo Boehme

Field Summary

Fields inherited from interface org.exist.dom.NodeSet

ANCESTOR, DESCENDANT, EMPTY_SET, FOLLOWING, PRECEDING

Fields inherited from interface org.exist.xquery.value.Sequence

EMPTY_SEQUENCE

Constructor Summary

VirtualNodeSet(int axis, NodeTest test, int contextId, NodeSet context)
Creates a new VirtualNodeSet instance.

Method Summary

void	add(DocumentImpl doc, long nodeId) The method add
void	add(Node node) The method add
void	add(NodeProxy proxy) The method add
void	addAll(NodeList other) The method addAll
void	addAll(NodeSet other) The method addAll
void	clearContext() The method clearContext
boolean	contains(NodeProxy p) The method contains
NodeSet	filterDocuments(NodeSet otherSet) The method filterDocuments
NodeProxy	get(DocumentImpl doc, NodeId nodeId) The method get
NodeProxy	get(int pos) The method get
NodeProxy	get(NodeProxy proxy) The method get
Iterator	getCollectionIterator() The method getCollectionIterator
DocumentSet	getDocumentSet() Returns the set of documents from which the node items in this sequence have been selected.
int	getItemCount() The method getItemCount
int	getLength() The method getLength
boolean	hasIndex()
boolean	hasMany() The method hasMany
boolean	hasOne() The method hasOne
NodeSet	intersection(NodeSet other) The method intersection
boolean	isEmpty() The method isEmpty
Node	item(int pos) The method item
Item	itemAt(int pos) The method itemAt
SequenceIterator	iterate() Returns an iterator over all items in the sequence.
NodeSetIterator	iterator() The method iterator
NodeProxy	parentWithChild(DocumentImpl doc, NodeId nodeId, boolean directParent, boolean includeSelf) The method parentWithChild
NodeProxy	parentWithChild(NodeProxy proxy, boolean directParent, boolean includeSelf, int level) The method parentWithChild
boolean	preferTreeTraversal() The method preferTreeTraversal
void	realize() The method realize
void	remove(NodeProxy node) The method remove
void	set(int position, DocumentImpl doc, long nodeId) The method set
void	setContextId(int contextId) The method setContextId
void	setInPredicate(boolean predicate) The method setInPredicate
void	setSelfIsContext() The method setSelfIsContext
String	toString() The method toString
NodeSet	union(NodeSet other) The method union
SequenceIterator	unorderedIterator() Returns an iterator over all items in the sequence.

Methods inherited from class org.exist.dom.AbstractNodeSet

add, add, addAll, clearContext, deepIntersection, directSelectAttribute, except, getAncestors, getContextNodes, getIndexType, getItemType, getParents, getProcessInReverseOrder, getSizeHint, getState, hasChanged, hasMixedContent, hasTextIndex, isCached, isPersistentSet, nodeMoved, removeDuplicates, selectAncestorDescendant, selectAncestors, selectFollowing, selectFollowingSiblings, selectParentChild, selectParentChild, selectPreceding, selectPrecedingSiblings, setIsCached, setProcessInReverseOrder, toNodeSet

Methods inherited from class org.exist.xquery.value.AbstractSequence

conversionPreference, convertTo, effectiveBooleanValue, getCardinality, getStringValue, setSelfAsContext, toJavaObject

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.exist.xquery.value.Sequence

conversionPreference, convertTo, effectiveBooleanValue, getCardinality, getStringValue, setSelfAsContext, toJavaObject

Constructor Detail

VirtualNodeSet

public VirtualNodeSet(int axis,
                      NodeTest test,
                      int contextId,
                      NodeSet context)

Creates a new VirtualNodeSet instance.

Parameters:

axis - an int value

test - a NodeTest value

contextId - an int value

context - a NodeSet value

Method Detail

contains

public boolean contains(NodeProxy p)

The method contains

Specified by:

contains in interface NodeSet

Specified by:

contains in class AbstractNodeSet

Parameters:

p - a NodeProxy value

Returns:

a boolean value

setInPredicate

public void setInPredicate(boolean predicate)

The method setInPredicate

Parameters:

predicate - a boolean value

getDocumentSet

public DocumentSet getDocumentSet()

Description copied from interface: Sequence

Returns the set of documents from which the node items in this sequence have been selected. This is for internal use only.

Specified by:

getDocumentSet in interface NodeSet

Specified by:

getDocumentSet in interface Sequence

Overrides:

getDocumentSet in class AbstractNodeSet

getCollectionIterator

public Iterator getCollectionIterator()

The method getCollectionIterator

Specified by:

getCollectionIterator in interface NodeSet

Specified by:

getCollectionIterator in interface Sequence

Overrides:

getCollectionIterator in class AbstractNodeSet

Returns:

an Iterator value

parentWithChild

public NodeProxy parentWithChild(NodeProxy proxy,
                                 boolean directParent,
                                 boolean includeSelf,
                                 int level)

The method parentWithChild

Specified by:

parentWithChild in interface NodeSet

Overrides:

parentWithChild in class AbstractNodeSet

Parameters:

proxy - a NodeProxy value

directParent - a boolean value

includeSelf - a boolean value

level - an int value

Returns:

a NodeProxy value

parentWithChild

public NodeProxy parentWithChild(DocumentImpl doc,
                                 NodeId nodeId,
                                 boolean directParent,
                                 boolean includeSelf)

The method parentWithChild

Specified by:

parentWithChild in interface NodeSet

Overrides:

parentWithChild in class AbstractNodeSet

Parameters:

doc - a DocumentImpl value

nodeId - a NodeId value

directParent - a boolean value

includeSelf - a boolean value

Returns:

a NodeProxy value

realize

public final void realize()

The method realize

preferTreeTraversal

public boolean preferTreeTraversal()

The method preferTreeTraversal

Returns:

a boolean value

setSelfIsContext

public void setSelfIsContext()

The method setSelfIsContext

setContextId

public void setContextId(int contextId)

The method setContextId

Parameters:

contextId - an int value

hasIndex

public boolean hasIndex()

isEmpty

public boolean isEmpty()

The method isEmpty

Specified by:

isEmpty in interface Sequence

Specified by:

isEmpty in class AbstractSequence

Returns:

a boolean value

hasOne

public boolean hasOne()

The method hasOne

Specified by:

hasOne in interface Sequence

Specified by:

hasOne in class AbstractSequence

Returns:

a boolean value

hasMany

public boolean hasMany()

The method hasMany

Specified by:

hasMany in interface Sequence

Overrides:

hasMany in class AbstractSequence

Returns:

a boolean value

add

public void add(DocumentImpl doc,
                long nodeId)

The method add

Parameters:

doc - a DocumentImpl value

nodeId - a long value

add

public void add(Node node)

The method add

Parameters:

node - a Node value

add

public void add(NodeProxy proxy)

The method add

Specified by:

add in interface NodeSet

Specified by:

add in class AbstractNodeSet

Parameters:

proxy - a NodeProxy value

addAll

public void addAll(NodeList other)

The method addAll

Parameters:

other - a NodeList value

addAll

public void addAll(NodeSet other)

The method addAll

Specified by:

addAll in interface NodeSet

Specified by:

addAll in class AbstractNodeSet

Parameters:

other - a NodeSet value

set

public void set(int position,
                DocumentImpl doc,
                long nodeId)

The method set

Parameters:

position - an int value

doc - a DocumentImpl value

nodeId - a long value

remove

public void remove(NodeProxy node)

The method remove

Parameters:

node - a NodeProxy value

getLength

public int getLength()

The method getLength

Specified by:

getLength in interface NodeList

Specified by:

getLength in class AbstractNodeSet

Returns:

an int value

getItemCount

public int getItemCount()

The method getItemCount

Specified by:

getItemCount in interface Sequence

Specified by:

getItemCount in class AbstractSequence

Returns:

an int value

item

public Node item(int pos)

The method item

Specified by:

item in interface NodeList

Specified by:

item in class AbstractNodeSet

Parameters:

pos - an int value

Returns:

a Node value

get

public NodeProxy get(int pos)

The method get

Specified by:

get in interface NodeSet

Specified by:

get in class AbstractNodeSet

Parameters:

pos - an int value

Returns:

a NodeProxy value

itemAt

public Item itemAt(int pos)

The method itemAt

Specified by:

itemAt in interface Sequence

Specified by:

itemAt in class AbstractSequence

Parameters:

pos - an int value

Returns:

an Item value

get

public NodeProxy get(DocumentImpl doc,
                     NodeId nodeId)

The method get

Parameters:

doc - a DocumentImpl value

nodeId - a NodeId value

Returns:

a NodeProxy value

get

public NodeProxy get(NodeProxy proxy)

The method get

Specified by:

get in interface NodeSet

Specified by:

get in class AbstractNodeSet

Parameters:

proxy - a NodeProxy value

Returns:

a NodeProxy value

iterator

public NodeSetIterator iterator()

The method iterator

Specified by:

iterator in interface NodeSet

Specified by:

iterator in class AbstractNodeSet

Returns:

a NodeSetIterator value

iterate

public SequenceIterator iterate()
                         throws XPathException

Description copied from interface: Sequence

Returns an iterator over all items in the sequence. The items are returned in document order where applicable.

Specified by:

iterate in interface Sequence

Specified by:

iterate in class AbstractNodeSet

Throws:

XPathException - TODO

unorderedIterator

public SequenceIterator unorderedIterator()

Description copied from interface: Sequence

Returns an iterator over all items in the sequence. The returned items may - but need not - to be in document order.

Specified by:

unorderedIterator in interface Sequence

Specified by:

unorderedIterator in class AbstractNodeSet

intersection

public NodeSet intersection(NodeSet other)

The method intersection

Specified by:

intersection in interface NodeSet

Overrides:

intersection in class AbstractNodeSet

Parameters:

other - a NodeSet value

Returns:

a NodeSet value

union

public NodeSet union(NodeSet other)

The method union

Specified by:

union in interface NodeSet

Overrides:

union in class AbstractNodeSet

Parameters:

other - a NodeSet value

Returns:

a NodeSet value

filterDocuments

public NodeSet filterDocuments(NodeSet otherSet)

The method filterDocuments

Specified by:

filterDocuments in interface NodeSet

Overrides:

filterDocuments in class AbstractNodeSet

Parameters:

otherSet - a NodeSet value

Returns:

a NodeSet value

clearContext

public void clearContext()

The method clearContext

toString

public String toString()

The method toString

Overrides:

toString in class AbstractNodeSet

Returns:

a String value