org.apache.xpath.axes
Class FilterExprWalker

java.lang.Object
  |
  +--org.apache.xpath.Expression
        |
        +--org.apache.xpath.patterns.NodeTest
              |
              +--org.apache.xpath.axes.PredicatedNodeTest
                    |
                    +--org.apache.xpath.axes.AxesWalker
                          |
                          +--org.apache.xpath.axes.FilterExprWalker

public class FilterExprWalker

extends AxesWalker

Walker for the OP_VARIABLE, or OP_EXTFUNCTION, or OP_FUNCTION, or OP_GROUP, op codes.

See Also:

XPath FilterExpr descriptions, Serialized Form

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

FEATURE_NODETESTFILTER

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

SCORE_NODETEST, SCORE_NONE, SCORE_NSWILD, SCORE_OTHER, SCORE_QNAME, SHOW_BYFUNCTION, SHOW_NAMESPACE, SUPPORTS_PRE_STRIPPING, WILD

Constructor Summary

FilterExprWalker(LocPathIterator locPathIterator)
Construct a FilterExprWalker using a LocPathIterator.

Method Summary

short	acceptNode(Node n) This method needs to override AxesWalker.acceptNode because FilterExprWalkers don't need to, and shouldn't, do a node test.
java.lang.Object	clone() Get a cloned FilterExprWalker.
Node	getNextNode() Moves the TreeWalker to the next visible node in document order relative to the current node, and returns the new node.
void	init(Compiler compiler, int opPos, int stepType) Init a FilterExprWalker.
void	setRoot(Node root) Set the root node of the TreeWalker.

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

canTraverseOutsideSubtree, firstChild, getCurrentNode, getExpandEntityReferences, getFilter, getLastPos, getNextWalker, getPrevWalker, getRoot, lastChild, nextNode, nextSibling, parentNode, previousNode, previousSibling, setCurrentNode, setNextWalker, setPrevWalker, toString

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

getLocPathIterator, getPredicateCount, getPredicateIndex, getProximityPosition, getProximityPosition, initProximityPosition, isReverseAxes, resetProximityPositions, setLocPathIterator, setPredicateCount

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

debugWhatToShow, execute, execute, getDefaultScore, getLocalName, getNamespace, getWhatToShow, initNodeTest, initNodeTest

Methods inherited from class org.apache.xpath.Expression

assertion, error, setSourceLocator, warn

Methods inherited from class java.lang.Object

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

Constructor Detail

FilterExprWalker

public FilterExprWalker(LocPathIterator locPathIterator)

Construct a FilterExprWalker using a LocPathIterator.

Parameters:

locPathIterator - non-null reference to the parent iterator.

Method Detail

init

public void init(Compiler compiler,
                 int opPos,
                 int stepType)
          throws TransformerException

Init a FilterExprWalker.

Parameters:

compiler - non-null reference to the Compiler that is constructing.

opPos - positive opcode position for this step.

stepType - The type of step.

Throws:

TransformerException -

Overrides:

init in class AxesWalker

setRoot

public void setRoot(Node root)

Set the root node of the TreeWalker.

Parameters:

root - non-null reference to the root, or starting point of the query.

Overrides:

setRoot in class AxesWalker

clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException

Get a cloned FilterExprWalker.

Returns:

A new FilterExprWalker that can be used without mutating this one.

Throws:

java.lang.CloneNotSupportedException -

Overrides:

clone in class AxesWalker

acceptNode

public short acceptNode(Node n)

This method needs to override AxesWalker.acceptNode because FilterExprWalkers don't need to, and shouldn't, do a node test.

Parameters:

n - The node to check to see if it passes the filter or not.

Returns:

a constant to determine whether the node is accepted, rejected, or skipped, as defined above .

Overrides:

acceptNode in class PredicatedNodeTest

getNextNode

public Node getNextNode()

Moves the TreeWalker to the next visible node in document order relative to the current node, and returns the new node. If the current node has no next node, or if the search for nextNode attempts to step upward from the TreeWalker's root node, returns null , and retains the current node.

Returns:

The new node, or null if the current node has no next node in the TreeWalker's logical view.