org.htmlunit.xpath.patterns

Class StepPattern

java.lang.Object

org.htmlunit.xpath.Expression

org.htmlunit.xpath.patterns.NodeTest

org.htmlunit.xpath.patterns.StepPattern

All Implemented Interfaces:

SourceLocator, SubContextList, ExpressionNode, XPathVisitable

Direct Known Subclasses:

ContextMatchStepPattern, FunctionPattern

public class StepPattern
extends NodeTest
implements SubContextList

This class represents a single pattern match step.

Field Summary

Fields

Modifier and Type	Field and Description
protected int	m_axis The axis for this test.

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

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

Constructor Summary

Constructors

Constructor and Description
StepPattern(int whatToShow, int axis) Construct a StepPattern that doesn't test for node names.
StepPattern(int whatToShow, String namespace, String name, int axis) Construct a StepPattern that tests for namespaces and node names.

Method Summary

Modifier and Type	Method and Description
void	calcScore() Static calc of match score.
void	calcTargetString() Calculate the local name or psuedo name of the node that this pattern will test, for hash table lookup optimization.
protected void	callSubtreeVisitors(XPathVisitor visitor) Call the visitors on the subtree.
void	callVisitors(XPathVisitor visitor) This will traverse the hierarchy, calling the visitor for each member.
boolean	canTraverseOutsideSubtree() Tell if this expression or it's subexpressions can traverse outside the current subtree.
boolean	deepEquals(Expression expr) Compare this object with another object and see if they are equal, include the sub heararchy.
XObject	execute(XPathContext xctxt) Execute an expression in the XPath runtime context, and return the result of the expression.
XObject	execute(XPathContext xctxt, int currentNode) Execute an expression in the XPath runtime context, and return the result of the expression.
XObject	execute(XPathContext xctxt, int currentNode, DTM dtm, int expType) Execute an expression in the XPath runtime context, and return the result of the expression.
protected boolean	executePredicates(XPathContext xctxt, DTM dtm, int currentNode) Execute the predicates on this step to determine if the current node should be filtered or accepted.
protected XObject	executeRelativePathPattern(XPathContext xctxt, DTM dtm, int currentNode) Execute the match pattern step relative to another step.
int	getAxis() Get the axis that this step follows.
int	getLastPos(XPathContext xctxt) Get the number of nodes in the node list, which, in the XSLT 1 based counting system, is the last index position.
Expression	getPredicate(int i) Get a predicate expression.
int	getPredicateCount() Get the number of predicates for this match pattern step.
Expression[]	getPredicates() Set the list of predicate expressions for this pattern step.
int	getProximityPosition(XPathContext xctxt) Get the current sub-context position.
StepPattern	getRelativePathPattern() Get the reference to nodetest and predicate for parent or ancestor.
void	setAxis(int axis) Set the axis that this step should follow.
void	setPredicates(Expression[] predicates) Set the predicates for this match pattern step.
void	setRelativePathPattern(StepPattern expr) Set the reference to nodetest and predicate for parent or ancestor.
String	toString()

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

getLocalName, getNamespace, getNodeTypeTest, getStaticScore, getWhatToShow, initNodeTest, initNodeTest, setLocalName, setNamespace, setStaticScore, setWhatToShow

Methods inherited from class org.htmlunit.xpath.Expression

asIterator, asNode, assertion, bool, error, execute, exprGetParent, exprSetParent, getColumnNumber, getExpressionOwner, getLineNumber, getPublicId, getSystemId, isSameClass, isStableNumber, num

Methods inherited from class java.lang.Object

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

Field Detail

m_axis

protected int m_axis

The axis for this test.

Constructor Detail

StepPattern

public StepPattern(int whatToShow,
                   String namespace,
                   String name,
                   int axis)

Construct a StepPattern that tests for namespaces and node names.

Parameters:

whatToShow - Bit set defined mainly by NodeFilter.

namespace - The namespace to be tested.

name - The local name to be tested.

axis - The Axis for this test, one of of Axes.ANCESTORORSELF, etc.

StepPattern

public StepPattern(int whatToShow,
                   int axis)

Construct a StepPattern that doesn't test for node names.

Parameters:

whatToShow - Bit set defined mainly by NodeFilter.

axis - The Axis for this test, one of of Axes.ANCESTORORSELF, etc.

Method Detail

calcTargetString

public void calcTargetString()

Calculate the local name or psuedo name of the node that this pattern will test, for hash table lookup optimization.

See Also:

PseudoNames

setRelativePathPattern

public void setRelativePathPattern(StepPattern expr)

Set the reference to nodetest and predicate for parent or ancestor.

Parameters:

expr - The relative pattern expression.

getRelativePathPattern

public StepPattern getRelativePathPattern()

Get the reference to nodetest and predicate for parent or ancestor.

Returns:

The relative pattern expression.

getPredicates

public Expression[] getPredicates()

Set the list of predicate expressions for this pattern step.

Returns:

List of expression objects.

canTraverseOutsideSubtree

public boolean canTraverseOutsideSubtree()

Tell if this expression or it's subexpressions can traverse outside the current subtree.

Overrides:

canTraverseOutsideSubtree in class Expression

Returns:

true if traversal outside the context node's subtree can occur.

getPredicate

public Expression getPredicate(int i)

Get a predicate expression.

Parameters:

i - The index of the predicate.

Returns:

A predicate expression.

getPredicateCount

public final int getPredicateCount()

Get the number of predicates for this match pattern step.

Returns:

the number of predicates for this match pattern step.

setPredicates

public void setPredicates(Expression[] predicates)

Set the predicates for this match pattern step.

Parameters:

predicates - An array of expressions that define predicates for this step.

calcScore

public void calcScore()

Static calc of match score.

Overrides:

calcScore in class NodeTest

execute

public XObject execute(XPathContext xctxt,
                       int currentNode)
                throws TransformerException

Execute an expression in the XPath runtime context, and return the result of the expression.

Overrides:

execute in class NodeTest

Parameters:

xctxt - The XPath runtime context.

currentNode - The currentNode.

Returns:

The result of the expression in the form of a XObject.

Throws:

TransformerException - if a runtime exception occurs.

execute

public XObject execute(XPathContext xctxt)
                throws TransformerException

Execute an expression in the XPath runtime context, and return the result of the expression.

Overrides:

execute in class NodeTest

Parameters:

xctxt - The XPath runtime context.

Returns:

The result of the expression in the form of a XObject.

Throws:

TransformerException - if a runtime exception occurs.

execute

public XObject execute(XPathContext xctxt,
                       int currentNode,
                       DTM dtm,
                       int expType)
                throws TransformerException

Execute an expression in the XPath runtime context, and return the result of the expression.

Overrides:

execute in class NodeTest

Parameters:

xctxt - The XPath runtime context.

currentNode - The currentNode.

dtm - The DTM of the current node.

expType - The expanded type ID of the current node.

Returns:

The result of the expression in the form of a XObject.

Throws:

TransformerException - if a runtime exception occurs.

getProximityPosition

public int getProximityPosition(XPathContext xctxt)

Get the current sub-context position.

Specified by:

getProximityPosition in interface SubContextList

Parameters:

xctxt - The XPath runtime context.

Returns:

The position of the current node in the list.

getLastPos

public int getLastPos(XPathContext xctxt)

Get the number of nodes in the node list, which, in the XSLT 1 based counting system, is the last index position.

Specified by:

getLastPos in interface SubContextList

Parameters:

xctxt - The XPath runtime context.

Returns:

the number of nodes in the node list.

executeRelativePathPattern

protected final XObject executeRelativePathPattern(XPathContext xctxt,
                                                   DTM dtm,
                                                   int currentNode)
                                            throws TransformerException

Execute the match pattern step relative to another step.

Parameters:

xctxt - The XPath runtime context.

dtm - The DTM of the current node.

currentNode - The current node context.

Returns:

NodeTest.SCORE_NODETEST, NodeTest.SCORE_NONE, NodeTest.SCORE_NSWILD, NodeTest.SCORE_QNAME, or NodeTest.SCORE_OTHER.

Throws:

TransformerException - in case of error

executePredicates

protected final boolean executePredicates(XPathContext xctxt,
                                          DTM dtm,
                                          int currentNode)
                                   throws TransformerException

Execute the predicates on this step to determine if the current node should be filtered or accepted.

Parameters:

xctxt - The XPath runtime context.

dtm - The DTM of the current node.

currentNode - The current node context.

Returns:

true if the node should be accepted, false otherwise.

Throws:

TransformerException - in case of error

toString

public String toString()

Overrides:

toString in class Object

setAxis

public void setAxis(int axis)

Set the axis that this step should follow.

Parameters:

axis - The Axis for this test, one of of Axes.ANCESTORORSELF, etc.

getAxis

public int getAxis()

Get the axis that this step follows.

Returns:

The Axis for this test, one of of Axes.ANCESTORORSELF, etc.

callVisitors

public void callVisitors(XPathVisitor visitor)

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

Specified by:

callVisitors in interface XPathVisitable

Overrides:

callVisitors in class NodeTest

Parameters:

visitor - The visitor whose appropriate method will be called.

callSubtreeVisitors

protected void callSubtreeVisitors(XPathVisitor visitor)

Call the visitors on the subtree. Factored out from callVisitors so it may be called by derived classes.

deepEquals

public boolean deepEquals(Expression expr)

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

Overrides:

deepEquals in class NodeTest

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.