org.apache.xpath.axes

Class FilterExprIteratorSimple

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.FilterExprIteratorSimple

All Implemented Interfaces:

Serializable, Cloneable, SourceLocator, DTMIterator, PathComponent, SubContextList, ExpressionNode, XPathVisitable

public class FilterExprIteratorSimple
extends LocPathIterator

Class to use for one-step iteration that doesn't have a predicate, and doesn't need to set the context.

See Also:

Serialized Form

Field Summary

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

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

m_foundLast, m_lpi, m_predCount, 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

Constructors

Constructor and Description
FilterExprIteratorSimple() Create a FilterExprIteratorSimple object.
FilterExprIteratorSimple(Expression expr) Create a FilterExprIteratorSimple object.

Method Summary

Methods

Modifier and Type	Method and Description
void	callPredicateVisitors(XPathVisitor visitor) This will traverse the heararchy, calling the visitor for each member.
boolean	deepEquals(Expression expr) Compare this object with another object and see if they are equal, include the sub heararchy.
void	detach() Detaches the walker from the set which it iterated over, releasing any computational resources and placing the iterator in the INVALID state.
static XNodeSet	executeFilterExpr(int context, XPathContext xctxt, PrefixResolver prefixResolver, boolean isTopLevel, int stackFrame, Expression expr) Execute the expression.
void	fixupVariables(Vector vars, int globalsSize) This function is used to fixup variables from QNames to stack frame indexes at stylesheet build time.
int	getAnalysisBits() Get the analysis bits for this walker, as defined in the WalkerFactory.
int	getAxis() Returns the axis being iterated, if it is known.
Expression	getInnerExpression() Get the inner contained expression of this filter.
boolean	isDocOrdered() Returns true if all the nodes in the iteration well be returned in document order.
int	nextNode() Returns the next node in the set and advances the position of the iterator in the set.
void	setInnerExpression(Expression expr) Set the inner contained expression of this filter.
void	setRoot(int context, Object environment) Initialize the context values for this expression after it is cloned.

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

allowDetachToRelease, asIterator, asNode, bool, callVisitors, cloneWithReset, execute, executeCharsToContentHandler, getContext, getCurrentContextNode, getCurrentNode, getCurrentPos, getDTM, getDTMManager, getExpandEntityReferences, getFilter, getFoundLast, getIsTopLevel, getLastPos, getLength, getPrefixResolver, getRoot, getWhatToShow, getXPathContext, incrementCurrentPos, 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, canTraverseOutsideSubtree, clone, countProximityPosition, 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

Constructor Detail

FilterExprIteratorSimple

public FilterExprIteratorSimple()

Create a FilterExprIteratorSimple object.

FilterExprIteratorSimple

public FilterExprIteratorSimple(Expression expr)

Create a FilterExprIteratorSimple object.

Method Detail

setRoot

public void setRoot(int context,
           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.

executeFilterExpr

public static XNodeSet executeFilterExpr(int context,
                         XPathContext xctxt,
                         PrefixResolver prefixResolver,
                         boolean isTopLevel,
                         int stackFrame,
                         Expression expr)
                                  throws WrappedRuntimeException

Execute the expression. Meant for reuse by other FilterExpr iterators that are not derived from this object.

Throws:

WrappedRuntimeException

nextNode

public int nextNode()

Returns the next node in the set and advances the position of the iterator in the set. After a NodeIterator is created, the first call to nextNode() returns the first node in the set.

Specified by:

nextNode in interface DTMIterator

Specified by:

nextNode in class LocPathIterator

Returns:

The next Node in the set being iterated over, or null if there are no more members in that set.

detach

public void detach()

Detaches the walker from the set which it iterated over, releasing any computational resources and placing the iterator in the INVALID state.

Specified by:

detach in interface DTMIterator

Overrides:

detach in class LocPathIterator

fixupVariables

public void fixupVariables(Vector vars,
                  int globalsSize)

This function is used to fixup variables from QNames to stack frame indexes at stylesheet build time.

Overrides:

fixupVariables in class PredicatedNodeTest

Parameters:

vars - List of QNames that correspond to variables. This list should be searched backwards for the first qualified name that corresponds to the variable reference qname. The position of the QName in the vector from the start of the vector will be its position in the stack frame (but variables above the globalsTop value will need to be offset to the current stack frame).

getInnerExpression

public Expression getInnerExpression()

Get the inner contained expression of this filter.

setInnerExpression

public void setInnerExpression(Expression expr)

Set the inner contained expression of this filter.

getAnalysisBits

public int getAnalysisBits()

Get the analysis bits for this walker, as defined in the WalkerFactory.

Specified by:

getAnalysisBits in interface PathComponent

Overrides:

getAnalysisBits in class LocPathIterator

Returns:

One of WalkerFactory#BIT_DESCENDANT, etc.

isDocOrdered

public boolean isDocOrdered()

Returns true if all the nodes in the iteration well be returned in document order. Warning: This can only be called after setRoot has been called!

Specified by:

isDocOrdered in interface DTMIterator

Overrides:

isDocOrdered in class LocPathIterator

Returns:

true as a default.

callPredicateVisitors

public void callPredicateVisitors(XPathVisitor visitor)

This will traverse the heararchy, calling the visitor for each member. If the called visitor method returns false, the subtree should not be called.

Overrides:

callPredicateVisitors in class PredicatedNodeTest

Parameters:

visitor - The visitor whose appropriate method will be called.

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)

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.