org.exist.dom
Class AbstractNodeSet

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

All Implemented Interfaces:

NodeSet, Sequence, NodeList

Direct Known Subclasses:

AVLTreeNodeSet, EmptyNodeSet, ExtArrayNodeSet, NewArrayNodeSet, SortedNodeSet, VirtualNodeSet

public abstract class AbstractNodeSet
extends AbstractSequence
implements NodeSet

Abstract base class for all node set implementations. A node set is a special type of sequence, which contains only nodes. Class NodeSet thus implements the Sequence as well as the DOM NodeList interfaces. Please note that a node set may or may not contain duplicate nodes. Some implementations (e.g. ExtArrayNodeSet) remove duplicates when sorting the set.

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

Method Summary

void	add(Item item) Add a sequence item to the node set.
abstract void	add(NodeProxy proxy) Add a new proxy object to the node set.
void	add(NodeProxy proxy, int sizeHint) Add a proxy object to the node set.
abstract void	addAll(NodeSet other) Add all nodes from the given node set.
void	addAll(Sequence other) Add all items from the given sequence to the node set.
void	clearContext(int contextId) For every item in the sequence, clear any context-dependant information that is stored during query processing.
abstract boolean	contains(NodeProxy proxy) Check if this node set contains a node matching the document and node-id of the given NodeProxy object.
NodeSet	deepIntersection(NodeSet other) Return a new node set, containing all nodes in this node set that are contained or have descendants in the other node set.
NodeSet	directSelectAttribute(DBBroker broker, NodeTest qname, int contextId) Optimized method to select attributes.
NodeSet	except(NodeSet other) Return a new node set containing all nodes from this node set except those nodes which are also contained in the argument node set.
NodeSet	filterDocuments(NodeSet otherSet) Create a new node set from this set containing only nodes in documents that are also contained in the argument set.
abstract NodeProxy	get(int pos) Get the node at position pos within this node set.
abstract NodeProxy	get(NodeProxy p) Get a node from this node set matching the document and node id of the given NodeProxy.
NodeSet	getAncestors(int contextId, boolean includeSelf) The method getAncestors
Iterator	getCollectionIterator() Return an iterator on all collections referenced by documents contained in this sequence..
NodeSet	getContextNodes(int contextId) Returns all context nodes associated with the nodes in this node set.
DocumentSet	getDocumentSet() Returns the set of documents from which the node items in this sequence have been selected.
int	getIndexType() If all nodes in this set have an index, returns the common supertype used to build the index, e.g.
int	getItemType() Return the primary type to which all items in this sequence belong.
abstract int	getLength() Return the number of nodes contained in this node set.
NodeSet	getParents(int contextId) Return a new node set containing the parent nodes of all nodes in the current set.
boolean	getProcessInReverseOrder()
int	getSizeHint(DocumentImpl doc) Get a hint about how many nodes in this node set belong to the specified document.
int	getState()
boolean	hasChanged(int previousState)
boolean	hasMixedContent()
boolean	hasTextIndex()
NodeSet	intersection(NodeSet other) Return a new node set, which represents the intersection of the current node set with the given node set.
boolean	isCached() Returns true if the sequence is the result of a previous operation and has been cached.
boolean	isPersistentSet()
abstract Node	item(int pos)
abstract SequenceIterator	iterate() Returns an iterator over all items in the sequence.
abstract NodeSetIterator	iterator() Return an iterator on the nodes in this list.
void	nodeMoved(NodeId oldNodeId, StoredNode newNode) Node sets may implement this method to be informed of storage address and node id changes after updates.
NodeProxy	parentWithChild(DocumentImpl doc, NodeId nodeId, boolean directParent, boolean includeSelf) Check if the node identified by its node id has an ancestor contained in this node set and return the ancestor found.
NodeProxy	parentWithChild(NodeProxy proxy, boolean directParent, boolean includeSelf, int level) Check if the given node has an ancestor contained in this node set and return the ancestor found.
void	removeDuplicates() Explicitely remove all duplicate nodes from this sequence.
NodeSet	selectAncestorDescendant(NodeSet al, int mode, boolean includeSelf, int contextId, boolean copyMatches) Check if any descendant nodes are found within this node set for a given set of potential ancestor nodes.
NodeSet	selectAncestors(NodeSet descendants, boolean includeSelf, int contextId) For a given set of potential ancestor nodes, return all ancestors having descendants in this node set.
NodeSet	selectFollowing(NodeSet fl, int contextId)
NodeSet	selectFollowing(NodeSet following, int position, int contextId)
NodeSet	selectFollowingSiblings(NodeSet siblings, int contextId) Select all nodes from the passed node set, which are following siblings of the nodes in this set.
NodeSet	selectParentChild(NodeSet al, int mode) Check if any child nodes are found within this node set for a given set of potential parent nodes.
NodeSet	selectParentChild(NodeSet al, int mode, int contextId) Check if any child nodes are found within this node set for a given set of potential ancestor nodes.
NodeSet	selectPreceding(NodeSet pl, int contextId)
NodeSet	selectPreceding(NodeSet preceding, int nth, int contextId)
NodeSet	selectPrecedingSiblings(NodeSet siblings, int contextId) Select all nodes from the passed node set, which are preceding or following siblings of the nodes in this set.
void	setIsCached(boolean cached) Indicates that the sequence is the result of a previous operation and has not been recomputed.
void	setProcessInReverseOrder(boolean inReverseOrder)
MemoryNodeSet	toMemNodeSet() Convert the sequence into an in-memory node set.
NodeSet	toNodeSet() Always returns this.
String	toString()
NodeSet	union(NodeSet other) Return a new node set which represents the union of the current node set and the given node set.
abstract SequenceIterator	unorderedIterator() Returns an iterator over all items in the sequence.

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

conversionPreference, convertTo, effectiveBooleanValue, getCardinality, getItemCount, getStringValue, hasMany, hasOne, isCacheable, isEmpty, itemAt, setSelfAsContext, toJavaObject

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.exist.dom.NodeSet

get

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

conversionPreference, convertTo, effectiveBooleanValue, getCardinality, getItemCount, getStringValue, hasMany, hasOne, isCacheable, isEmpty, itemAt, setSelfAsContext, toJavaObject

Method Detail

iterator

public abstract NodeSetIterator iterator()

Return an iterator on the nodes in this list. The iterator returns nodes according to the internal ordering of nodes (i.e. level first), not in document- order.

Specified by:

iterator in interface NodeSet

iterate

public abstract 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 AbstractSequence

Throws:

XPathException - TODO

unorderedIterator

public abstract SequenceIterator unorderedIterator()
                                            throws XPathException

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 AbstractSequence

Throws:

XPathException

getItemType

public int getItemType()

Description copied from interface: Sequence

Return the primary type to which all items in this sequence belong. This is Type.NODE for node sets, Type.ITEM for other sequences with mixed items.

Specified by:

getItemType in interface Sequence

Specified by:

getItemType in class AbstractSequence

Returns:

the primary type of the items in this sequence.

contains

public abstract boolean contains(NodeProxy proxy)

Check if this node set contains a node matching the document and node-id of the given NodeProxy object.

Specified by:

contains in interface NodeSet

Parameters:

proxy -

add

public abstract void add(NodeProxy proxy)

Add a new proxy object to the node set. Please note: node set implementations may allow duplicates.

Specified by:

add in interface NodeSet

Parameters:

proxy -

add

public void add(NodeProxy proxy,
                int sizeHint)

Add a proxy object to the node set. The sizeHint parameter gives a hint about the number of items to be expected for the current document.

Specified by:

add in interface NodeSet

Parameters:

proxy -

sizeHint -

add

public void add(Item item)
         throws XPathException

Add a sequence item to the node set. The item has to be a subtype of node.

Specified by:

add in interface Sequence

Specified by:

add in class AbstractSequence

Throws:

XPathException

addAll

public void addAll(Sequence other)
            throws XPathException

Add all items from the given sequence to the node set. All items have to be a subtype of node.

Specified by:

addAll in interface Sequence

Overrides:

addAll in class AbstractSequence

Parameters:

other -

Throws:

XPathException

addAll

public abstract void addAll(NodeSet other)

Add all nodes from the given node set.

Specified by:

addAll in interface NodeSet

Parameters:

other -

getLength

public abstract int getLength()

Return the number of nodes contained in this node set.

Specified by:

getLength in interface NodeList

setIsCached

public void setIsCached(boolean cached)

Description copied from interface: Sequence

Indicates that the sequence is the result of a previous operation and has not been recomputed.

Specified by:

setIsCached in interface Sequence

Overrides:

setIsCached in class AbstractSequence

isCached

public boolean isCached()

Description copied from interface: Sequence

Returns true if the sequence is the result of a previous operation and has been cached.

Specified by:

isCached in interface Sequence

Overrides:

isCached in class AbstractSequence

removeDuplicates

public void removeDuplicates()

Description copied from interface: Sequence

Explicitely remove all duplicate nodes from this sequence.

Specified by:

removeDuplicates in interface Sequence

item

public abstract Node item(int pos)

Specified by:

item in interface NodeList

get

public abstract NodeProxy get(int pos)

Get the node at position pos within this node set.

Specified by:

get in interface NodeSet

Parameters:

pos -

get

public abstract NodeProxy get(NodeProxy p)

Get a node from this node set matching the document and node id of the given NodeProxy.

Specified by:

get in interface NodeSet

Parameters:

p -

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 AbstractSequence

getCollectionIterator

public Iterator getCollectionIterator()

Description copied from interface: Sequence

Return an iterator on all collections referenced by documents contained in this sequence..

Specified by:

getCollectionIterator in interface NodeSet

Specified by:

getCollectionIterator in interface Sequence

Overrides:

getCollectionIterator in class AbstractSequence

selectParentChild

public NodeSet selectParentChild(NodeSet al,
                                 int mode)

Check if any child nodes are found within this node set for a given set of potential parent nodes. If mode is NodeSet.DESCENDANT, the returned node set will contain all child nodes found in this node set for each parent node. If mode is NodeSet.ANCESTOR, the returned set will contain those parent nodes, for which children have been found.

Specified by:

selectParentChild in interface NodeSet

Parameters:

al - a node set containing potential parent nodes

mode - selection mode

selectParentChild

public NodeSet selectParentChild(NodeSet al,
                                 int mode,
                                 int contextId)

Check if any child nodes are found within this node set for a given set of potential ancestor nodes. If mode is NodeSet.DESCENDANT, the returned node set will contain all child nodes found in this node set for each parent node. If mode is NodeSet.ANCESTOR, the returned set will contain those parent nodes, for which children have been found.

Specified by:

selectParentChild in interface NodeSet

Parameters:

al - a node set containing potential parent nodes

mode - selection mode

contextId - used to track context nodes when evaluating predicate expressions. If contextId != Expression.NO_CONTEXT_ID, the current context will be added to each result of the of the selection.

selectAncestorDescendant

public NodeSet selectAncestorDescendant(NodeSet al,
                                        int mode,
                                        boolean includeSelf,
                                        int contextId,
                                        boolean copyMatches)

Check if any descendant nodes are found within this node set for a given set of potential ancestor nodes. If mode is NodeSet.DESCENDANT, the returned node set will contain all descendant nodes found in this node set for each ancestor. If mode is NodeSet.ANCESTOR, the returned set will contain those ancestor nodes, for which descendants have been found.

Specified by:

selectAncestorDescendant in interface NodeSet

Parameters:

al - a node set containing potential parent nodes

mode - selection mode

includeSelf - if true, check if the ancestor node itself is contained in the set of descendant nodes (descendant-or-self axis)

contextId - used to track context nodes when evaluating predicate expressions. If contextId != Expression.NO_CONTEXT_ID, the current context will be added to each result of the selection.

selectAncestors

public NodeSet selectAncestors(NodeSet descendants,
                               boolean includeSelf,
                               int contextId)

For a given set of potential ancestor nodes, return all ancestors having descendants in this node set.

Specified by:

selectAncestors in interface NodeSet

Parameters:

descendants - node set containing potential ancestors

includeSelf - if true, check if the ancestor node itself is contained in this node set (ancestor-or-self axis)

contextId -

selectFollowing

public NodeSet selectFollowing(NodeSet fl,
                               int contextId)
                        throws XPathException

Specified by:

selectFollowing in interface NodeSet

Throws:

XPathException

selectFollowing

public NodeSet selectFollowing(NodeSet following,
                               int position,
                               int contextId)
                        throws XPathException

Specified by:

selectFollowing in interface NodeSet

Throws:

XPathException

selectPreceding

public NodeSet selectPreceding(NodeSet pl,
                               int contextId)
                        throws XPathException

Specified by:

selectPreceding in interface NodeSet

Throws:

XPathException

selectPreceding

public NodeSet selectPreceding(NodeSet preceding,
                               int nth,
                               int contextId)
                        throws XPathException,
                               UnsupportedOperationException

Specified by:

selectPreceding in interface NodeSet

Throws:

XPathException

UnsupportedOperationException

selectPrecedingSiblings

public NodeSet selectPrecedingSiblings(NodeSet siblings,
                                       int contextId)

Select all nodes from the passed node set, which are preceding or following siblings of the nodes in this set. If mode is NodeSet.FOLLOWING, only nodes following the context node are selected. NodeSet.PRECEDING selects preceding nodes.

Specified by:

selectPrecedingSiblings in interface NodeSet

Parameters:

siblings - a node set containing potential siblings

contextId - used to track context nodes when evaluating predicate expressions. If contextId != Expression.NO_CONTEXT_ID, the current context will be added to each result of the of the selection.

selectFollowingSiblings

public NodeSet selectFollowingSiblings(NodeSet siblings,
                                       int contextId)

Description copied from interface: NodeSet

Select all nodes from the passed node set, which are following siblings of the nodes in this set.

Specified by:

selectFollowingSiblings in interface NodeSet

Parameters:

siblings - a node set containing potential siblings

contextId - used to track context nodes when evaluating predicate expressions. If contextId != Expression.NO_CONTEXT_ID, the current context will be added to each result of the of the selection.

directSelectAttribute

public NodeSet directSelectAttribute(DBBroker broker,
                                     NodeTest qname,
                                     int contextId)

Description copied from interface: NodeSet

Optimized method to select attributes. Use this if the context has just one or two nodes. Attributes will be directly looked up in the persistent DOM store.

Specified by:

directSelectAttribute in interface NodeSet

qname - a node test

contextId - used to track context nodes when evaluating predicate expressions. If contextId != Expression.NO_CONTEXT_ID, the current context will be added to each result of the of the selection.

parentWithChild

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

Description copied from interface: NodeSet

Check if the node identified by its node id has an ancestor contained in this node set and return the ancestor found. If directParent is true, only immediate ancestors (parents) are considered. Otherwise the method will call itself recursively for all the node's parents. If includeSelf is true, the method returns also true if the node itself is contained in the node set.

Specified by:

parentWithChild in interface NodeSet

parentWithChild

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

Check if the given node has an ancestor contained in this node set and return the ancestor found. If directParent is true, only immediate ancestors (parents) are considered. Otherwise the method will call itself recursively for all the node's parents. If includeSelf is true, the method returns also true if the node itself is contained in the node set.

Specified by:

parentWithChild in interface NodeSet

getParents

public NodeSet getParents(int contextId)

Return a new node set containing the parent nodes of all nodes in the current set.

Specified by:

getParents in interface NodeSet

Parameters:

contextId - an int value

Returns:

a NodeSet value

getAncestors

public NodeSet getAncestors(int contextId,
                            boolean includeSelf)

The method getAncestors

Specified by:

getAncestors in interface NodeSet

Parameters:

contextId - an int value

includeSelf - a boolean value

Returns:

a NodeSet value

getSizeHint

public int getSizeHint(DocumentImpl doc)

Get a hint about how many nodes in this node set belong to the specified document. This is just used for allocating new node sets. The information does not need to be exact. -1 is returned if the size cannot be determined (the default).

Specified by:

getSizeHint in interface NodeSet

Parameters:

doc -

intersection

public NodeSet intersection(NodeSet other)

Return a new node set, which represents the intersection of the current node set with the given node set.

Specified by:

intersection in interface NodeSet

Parameters:

other -

deepIntersection

public NodeSet deepIntersection(NodeSet other)

Description copied from interface: NodeSet

Return a new node set, containing all nodes in this node set that are contained or have descendants in the other node set.

Specified by:

deepIntersection in interface NodeSet

except

public NodeSet except(NodeSet other)

Description copied from interface: NodeSet

Return a new node set containing all nodes from this node set except those nodes which are also contained in the argument node set.

Specified by:

except in interface NodeSet

filterDocuments

public NodeSet filterDocuments(NodeSet otherSet)

Description copied from interface: NodeSet

Create a new node set from this set containing only nodes in documents that are also contained in the argument set.

Specified by:

filterDocuments in interface NodeSet

setProcessInReverseOrder

public void setProcessInReverseOrder(boolean inReverseOrder)

Specified by:

setProcessInReverseOrder in interface NodeSet

getProcessInReverseOrder

public boolean getProcessInReverseOrder()

Specified by:

getProcessInReverseOrder in interface NodeSet

union

public NodeSet union(NodeSet other)

Return a new node set which represents the union of the current node set and the given node set.

Specified by:

union in interface NodeSet

Parameters:

other -

getContextNodes

public NodeSet getContextNodes(int contextId)

Returns all context nodes associated with the nodes in this node set.

Specified by:

getContextNodes in interface NodeSet

Parameters:

contextId - used to track context nodes when evaluating predicate expressions. If contextId != Expression.NO_CONTEXT_ID, the current context will be added to each result of the of the selection.

toNodeSet

public NodeSet toNodeSet()
                  throws XPathException

Always returns this.

Specified by:

toNodeSet in interface Sequence

Throws:

XPathException - if the sequence contains items which are not nodes.

See Also:

Sequence.toNodeSet()

toMemNodeSet

public MemoryNodeSet toMemNodeSet()
                           throws XPathException

Description copied from interface: Sequence

Convert the sequence into an in-memory node set. If the sequence contains items which are not nodes, an XPathException is thrown. For persistent node sets, this method will return null. Call Sequence.isPersistentSet() to check if the sequence is a persistent node set.

Specified by:

toMemNodeSet in interface Sequence

Throws:

XPathException - if the sequence contains items which are not nodes or is a persistent node set

getState

public int getState()

Specified by:

getState in interface NodeSet

Specified by:

getState in interface Sequence

Overrides:

getState in class AbstractSequence

hasChanged

public boolean hasChanged(int previousState)

Specified by:

hasChanged in interface NodeSet

Specified by:

hasChanged in interface Sequence

Overrides:

hasChanged in class AbstractSequence

getIndexType

public int getIndexType()

If all nodes in this set have an index, returns the common supertype used to build the index, e.g. xs:integer or xs:string. If the nodes have different index types or no node has been indexed, returns Type.ITEM.

Specified by:

getIndexType in interface NodeSet

See Also:

GeneralComparison, ValueComparison

hasTextIndex

public boolean hasTextIndex()

Specified by:

hasTextIndex in interface NodeSet

hasMixedContent

public boolean hasMixedContent()

Specified by:

hasMixedContent in interface NodeSet

clearContext

public void clearContext(int contextId)
                  throws XPathException

Description copied from interface: Sequence

For every item in the sequence, clear any context-dependant information that is stored during query processing. This feature is used for node sets, which may store information about their context node.

Specified by:

clearContext in interface Sequence

Overrides:

clearContext in class AbstractSequence

Throws:

XPathException

nodeMoved

public void nodeMoved(NodeId oldNodeId,
                      StoredNode newNode)

Description copied from interface: Sequence

Node sets may implement this method to be informed of storage address and node id changes after updates.

Specified by:

nodeMoved in interface Sequence

Overrides:

nodeMoved in class AbstractSequence

See Also:

UpdateListener

isPersistentSet

public boolean isPersistentSet()

Specified by:

isPersistentSet in interface Sequence

Overrides:

isPersistentSet in class AbstractSequence

toString

public String toString()

Overrides:

toString in class AbstractSequence