org.apache.xpath.axes
Class OneStepIteratorForward

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
                          org.apache.xpath.axes.OneStepIteratorForward

All Implemented Interfaces:

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

Direct Known Subclasses:

KeyIterator

public class OneStepIteratorForward
extends ChildTestIterator

This class implements a general iterator for those LocationSteps with only one step, and perhaps a predicate, that only go forward (i.e. it can not be used with ancestors, preceding, etc.)

See Also:

org.apache.xpath.axes, Serialized Form

Nested Class Summary

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

PredicatedNodeTest.PredOwner

Field Summary

protected int	m_axis The traversal axis from where the nodes will be filtered.
(package private) static long	serialVersionUID

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

m_traverser

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

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

OneStepIteratorForward(int axis)
Create a OneStepIterator object that will just traverse the self axes.

Method Summary

boolean	deepEquals(Expression expr) Compare this object with another object and see if they are equal, include the sub heararchy.
int	getAxis() Returns the axis being iterated, if it is known.
protected int	getNextNode() Get the next node via getFirstAttribute && getNextAttribute.
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.ChildTestIterator

cloneWithReset, detach

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, 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_axis

protected int m_axis

The traversal axis from where the nodes will be filtered.

Constructor Detail

OneStepIteratorForward

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

Create a OneStepIterator 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

OneStepIteratorForward

public OneStepIteratorForward(int axis)

Create a OneStepIterator object that will just traverse the self axes.

Parameters:

axis - One of the org.apache.xml.dtm.Axis integers.

Throws:

javax.xml.transform.TransformerException

Method Detail

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 ChildTestIterator

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.

getNextNode

protected int getNextNode()

Get the next node via getFirstAttribute && getNextAttribute.

Overrides:

getNextNode in class ChildTestIterator

Returns:

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

getAxis

public int getAxis()

Returns the axis being iterated, if it is known.

Specified by:

getAxis in interface DTMIterator

Overrides:

getAxis in class ChildTestIterator

Returns:

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

deepEquals

public boolean deepEquals(Expression expr)

Description copied from class: Expression

Compare this object with another object and see if they are equal, include the sub heararchy.

Overrides:

deepEquals in class PredicatedNodeTest

Parameters:

expr - Another expression object.

Returns:

true if this objects class and the expr object's class are the same, and the data contained within both objects are considered equal.

See Also:

Expression.deepEquals(Expression)