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
Method Summary |
short |
acceptNode(int 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. |
void |
fixupVariables(java.util.Vector vars,
int globalsSize)
This function is used to fixup variables from QNames to stack frame
indexes at stylesheet build time. |
int |
getAxis()
Returns the axis being iterated, if it is known. |
int |
getLastPos(XPathContext xctxt)
Get the index of the last node that can be itterated to. |
int |
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. |
boolean |
isDocOrdered()
Returns true if all the nodes in the iteration well be returned in document
order. |
void |
setRoot(int root)
Set the root node of the TreeWalker. |
Methods inherited from class org.apache.xpath.axes.PredicatedNodeTest |
canTraverseOutsideSubtree,
getLocPathIterator,
getPredicateCount,
getPredicateIndex,
getProximityPosition,
getProximityPosition,
initProximityPosition,
isReverseAxes,
resetProximityPositions,
setLocPathIterator,
setPredicateCount |
Methods inherited from class org.apache.xpath.patterns.NodeTest |
debugWhatToShow,
execute,
execute,
execute,
getDefaultScore,
getLocalName,
getNamespace,
getNodeTypeTest,
getStaticScore,
getWhatToShow,
initNodeTest,
initNodeTest,
setLocalName,
setNamespace,
setStaticScore,
setWhatToShow |
Methods inherited from class org.apache.xpath.Expression |
asIterator,
asNode,
assertion,
bool,
error,
executeCharsToContentHandler,
isNodesetExpr,
isStableNumber,
num,
setSourceLocator,
warn,
xstr |
Methods inherited from class java.lang.Object |
equals,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait |
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(int 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(int 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 int 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.
getLastPos
public int getLastPos(XPathContext xctxt)
- Get the index of the last node that can be itterated to.
- Parameters:
xctxt
- XPath runtime context.- Returns:
- the index of the last node that can be itterated to.
- Overrides:
- getLastPos in class AxesWalker
fixupVariables
public void fixupVariables(java.util.Vector vars,
int globalsSize)
- This function is used to fixup variables from QNames to stack frame
indexes at stylesheet build time.
- 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).- Overrides:
- fixupVariables in class PredicatedNodeTest
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!
- Returns:
- true as a default.
- Overrides:
- isDocOrdered in class AxesWalker
getAxis
public int getAxis()
- Returns the axis being iterated, if it is known.
- Returns:
- Axis.CHILD, etc., or -1 if the axis is not known or is of multiple
types.
- Overrides:
- getAxis in class AxesWalker
Copyright © 2001 Apache XML Project. All Rights Reserved.