org.apache.xpath.axes
Class ChildTestIterator

java.lang.Object
  org.apache.xpath.Expression
      org.apache.xpath.patterns.NodeTest
          org.apache.xpath.axes.PredicatedNodeTest
              org.apache.xpath.axes.LocPathIterator
                  org.apache.xpath.axes.BasicTestIterator
                      org.apache.xpath.axes.ChildTestIterator

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, javax.xml.transform.SourceLocator, DTMIterator, PathComponent, SubContextList, ExpressionNode, XPathVisitable

Direct Known Subclasses:

AttributeIterator, KeyRefIterator, OneStepIterator, OneStepIteratorForward, UnionChildIterator

public class ChildTestIterator
extends BasicTestIterator

This class implements an optimized iterator for children patterns that have a node test, and possibly a predicate.

See Also:

BasicTestIterator, Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.xpath.axes.PredicatedNodeTest

PredicatedNodeTest.PredOwner

Field Summary

protected DTMAxisTraverser	m_traverser The traverser to use to navigate over the descendants.
(package private) static long	serialVersionUID

Fields inherited from class org.apache.xpath.axes.LocPathIterator

m_allowDetach, m_cdtm, m_clones, m_context, m_currentContextNode, m_execContext, m_lastFetched, m_length, m_pos, m_stackFrame

Fields inherited from class org.apache.xpath.axes.PredicatedNodeTest

DEBUG_PREDICATECOUNTING, m_foundLast, m_lpi, m_predCount, m_predicateIndex, m_proximityPositions

Fields inherited from class org.apache.xpath.patterns.NodeTest

m_name, m_whatToShow, SCORE_NODETEST, SCORE_NONE, SCORE_NSWILD, SCORE_OTHER, SCORE_QNAME, SHOW_BYFUNCTION, SUPPORTS_PRE_STRIPPING, WILD

Fields inherited from interface org.apache.xml.dtm.DTMIterator

FILTER_ACCEPT, FILTER_REJECT, FILTER_SKIP

Constructor Summary

ChildTestIterator(Compiler compiler, int opPos, int analysis)
Create a ChildTestIterator object.

ChildTestIterator(DTMAxisTraverser traverser)
Create a ChildTestIterator object.

Method Summary

DTMIterator	cloneWithReset() Get a cloned Iterator that is reset to the beginning of the query.
void	detach() Detaches the iterator from the set which it iterated over, releasing any computational resources and placing the iterator in the INVALID state.
int	getAxis() Returns the axis being iterated, if it is known.
protected int	getNextNode() Get the next node via getNextXXX.
void	setRoot(int context, java.lang.Object environment) Initialize the context values for this expression after it is cloned.

Methods inherited from class org.apache.xpath.axes.BasicTestIterator

nextNode

Methods inherited from class org.apache.xpath.axes.LocPathIterator

allowDetachToRelease, asIterator, asNode, bool, callVisitors, execute, executeCharsToContentHandler, getAnalysisBits, getContext, getCurrentContextNode, getCurrentNode, getCurrentPos, getDTM, getDTMManager, getExpandEntityReferences, getFilter, getFoundLast, getIsTopLevel, getLastPos, getLength, getPrefixResolver, getRoot, getWhatToShow, getXPathContext, incrementCurrentPos, isDocOrdered, isFresh, isMutable, isNodesetExpr, item, previousNode, reset, returnNextNode, runTo, setCurrentContextNode, setCurrentPos, setEnvironment, setIsTopLevel, setItem, setNextPosition, setShouldCacheNodes, size

Methods inherited from class org.apache.xpath.axes.PredicatedNodeTest

acceptNode, callPredicateVisitors, canTraverseOutsideSubtree, clone, countProximityPosition, deepEquals, executePredicates, fixupVariables, getLocPathIterator, getPredicate, getPredicateCount, getPredicateIndex, getProximityPosition, getProximityPosition, getProximityPosition, initPredicateInfo, initProximityPosition, isReverseAxes, nodeToString, resetProximityPositions, setLocPathIterator, setPredicateCount

Methods inherited from class org.apache.xpath.patterns.NodeTest

calcScore, debugWhatToShow, execute, execute, getDefaultScore, getLocalName, getNamespace, getNodeTypeTest, getStaticScore, initNodeTest, initNodeTest, setLocalName, setNamespace, setStaticScore, setWhatToShow

Methods inherited from class org.apache.xpath.Expression

asIteratorRaw, assertion, error, execute, exprAddChild, exprGetChild, exprGetNumChildren, exprGetParent, exprSetParent, getColumnNumber, getExpressionOwner, getLineNumber, getPublicId, getSystemId, isSameClass, isStableNumber, num, warn, xstr

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.xml.dtm.DTMIterator

clone

Field Detail

serialVersionUID

static final long serialVersionUID

See Also:

Constant Field Values

m_traverser

protected transient DTMAxisTraverser m_traverser

The traverser to use to navigate over the descendants.

Constructor Detail

ChildTestIterator

ChildTestIterator(Compiler compiler,
                  int opPos,
                  int analysis)
            throws javax.xml.transform.TransformerException

Create a ChildTestIterator object.

Parameters:

compiler - A reference to the Compiler that contains the op map.

opPos - The position within the op map, which contains the location path expression for this itterator.

Throws:

javax.xml.transform.TransformerException

ChildTestIterator

public ChildTestIterator(DTMAxisTraverser traverser)

Create a ChildTestIterator object.

Parameters:

traverser - Traverser that tells how the KeyIterator is to be handled.

Throws:

javax.xml.transform.TransformerException

Method Detail

getNextNode

protected int getNextNode()

Get the next node via getNextXXX. Bottlenecked for derived class override.

Specified by:

getNextNode in class BasicTestIterator

Returns:

The next node on the axis, or DTM.NULL.

cloneWithReset

public DTMIterator cloneWithReset()
                           throws java.lang.CloneNotSupportedException

Get a cloned Iterator that is reset to the beginning of the query.

Specified by:

cloneWithReset in interface DTMIterator

Overrides:

cloneWithReset in class BasicTestIterator

Returns:

A cloned NodeIterator set of the start of the query.

Throws:

java.lang.CloneNotSupportedException

setRoot

public void setRoot(int context,
                    java.lang.Object environment)

Initialize the context values for this expression after it is cloned.

Specified by:

setRoot in interface DTMIterator

Overrides:

setRoot in class LocPathIterator

Parameters:

context - The XPath runtime context for this transformation.

environment - The environment object. The environment in which this iterator operates, which should provide:

• a node (the context node... same value as "root" defined below)
• a pair of non-zero positive integers (the context position and the context size)
• a set of variable bindings
• a function library
• the set of namespace declarations in scope for the expression.

At this time the exact implementation of this environment is application dependent. Probably a proper interface will be created fairly soon.

getAxis

public int getAxis()

Returns the axis being iterated, if it is known.

Specified by:

getAxis in interface DTMIterator

Overrides:

getAxis in class LocPathIterator

Returns:

Axis.CHILD, etc., or -1 if the axis is not known or is of multiple types.

detach

public void detach()

Detaches the iterator from the set which it iterated over, releasing any computational resources and placing the iterator in the INVALID state. Afterdetach has been invoked, calls to nextNode orpreviousNode will raise the exception INVALID_STATE_ERR.

Specified by:

detach in interface DTMIterator

Overrides:

detach in class LocPathIterator