com.icl.saxon.pattern

Class LocationPathPattern


public final class LocationPathPattern
extends Pattern

A LocationPathPattern represents a path, e.g. of the form A/B/C... The components are represented as a linked list, each component pointing to its predecessor

Field Summary

Pattern
ancestorPattern
protected Expression
equivalentExpr
protected Expression[]
filters
protected boolean
firstElementPattern
protected boolean
lastElementPattern
NodeTest
nodeTest
protected int
numberOfFilters
Pattern
parentPattern
protected boolean
specialFilter

Fields inherited from class com.icl.saxon.pattern.Pattern

originalText, staticContext

Method Summary

void
addFilter(Expression filter)
Add a filter to the pattern (while under construction)
int
getFingerprint()
Determine the fingerprint of nodes to which this pattern applies.
short
getNodeType()
Determine the types of nodes to which this pattern applies.
boolean
isRelative()
Determine if the pattern uses positional filters
boolean
matches(NodeInfo node, Context context)
Determine whether this Pattern matches the given Node
boolean
matchesX(NodeInfo node, Context context)
Determine whether the pattern matches a given node.
Pattern
simplify()
Simplify the pattern: perform any context-independent optimisations

Methods inherited from class com.icl.saxon.pattern.Pattern

getDefaultPriority, getFingerprint, getLineNumber, getNodeType, getStaticContext, getSystemId, make, matches, setOriginalText, setStaticContext, simplify, toString

Field Details

ancestorPattern

public Pattern ancestorPattern


equivalentExpr

protected Expression equivalentExpr


filters

protected Expression[] filters


firstElementPattern

protected boolean firstElementPattern


lastElementPattern

protected boolean lastElementPattern


nodeTest

public NodeTest nodeTest


numberOfFilters

protected int numberOfFilters


parentPattern

public Pattern parentPattern


specialFilter

protected boolean specialFilter

Method Details

addFilter

public void addFilter(Expression filter)
Add a filter to the pattern (while under construction)

Parameters:
filter - The predicate (a boolean expression or numeric expression) to be added


getFingerprint

public int getFingerprint()
Determine the fingerprint of nodes to which this pattern applies. Used for optimisation.
Overrides:
getFingerprint in interface Pattern

Returns:
the fingerprint of nodes matched by this pattern.


getNodeType

public short getNodeType()
Determine the types of nodes to which this pattern applies. Used for optimisation. For patterns that match nodes of several types, return Node.NODE
Overrides:
getNodeType in interface Pattern

Returns:
the type of node matched by this pattern. e.g. Node.ELEMENT or Node.TEXT


isRelative

public boolean isRelative()
            throws XPathException
Determine if the pattern uses positional filters

Returns:
true if there is a numeric filter in the pattern, or one that uses the position() or last() functions


matches

public boolean matches(NodeInfo node,
                       Context context)
            throws XPathException
Determine whether this Pattern matches the given Node
Overrides:
matches in interface Pattern

Parameters:
node - The NodeInfo representing the Element or other node to be tested against the Pattern
context - The context in which the match is to take place. Only relevant if the pattern uses variables.

Returns:
true if the node matches the Pattern, false otherwise


matchesX

public boolean matchesX(NodeInfo node,
                        Context context)
            throws XPathException
Determine whether the pattern matches a given node.

Parameters:
node - the node to be tested

Returns:
true if the pattern matches, else false


simplify

public Pattern simplify()
            throws XPathException
Simplify the pattern: perform any context-independent optimisations
Overrides:
simplify in interface Pattern