org.exolab.adaptx.xpath.expressions
Interface PathComponent

All Superinterfaces:

MatchExpression, XPathExpression

All Known Subinterfaces:

LocationStep

All Known Implementing Classes:

FilterBase

public interface PathComponent

extends XPathExpression, MatchExpression

A basic interface for LocationStep or FilterExpr

Version:

$Revision: 1.1 $ $Date: 2003/05/13 07:55:04 $

Author:

Keith Visco

Field Summary

Fields inherited from interface org.exolab.adaptx.xpath.XPathExpression

BOOLEAN, ERROR, FILTER_EXPR, LOCATION_PATH, NODE_TEST, NUMBER, PATH_EXPR, PRIMARY, STEP, STRING, UNION_EXPR

Method Summary

void	evaluatePredicates(NodeSet nodes, XPathContext context) Evaluates the PredicateExpr of this PathComponent against the given NodeSet and XPathContext.
double	getDefaultPriority() Determines the priority of a PatternExpr as follows:
PredicateExpr	getPredicate() Returns the PredicateExpr of this PathComponent
boolean	hasPredicates() Returns true if this PathComponent has predicates expressions.

Methods inherited from interface org.exolab.adaptx.xpath.XPathExpression

evaluate, getExprType, toString

Methods inherited from interface org.exolab.adaptx.xpath.expressions.MatchExpression

matches

Method Detail

getDefaultPriority

public double getDefaultPriority()

Determines the priority of a PatternExpr as follows:

  From the 19991116 XSLT 1.0 Recommendation:
  + If the pattern has the form of a QName preceded by a
    ChildOrAttributeAxisSpecifier or has the form 
    processing-instruction(Literal) then the priority is 0.
  + If the pattern has the form NCName:* preceded by a 
    ChildOrAttributeAxisSpecifier, then the priority is -0.25
  + Otherwise if the pattern consists of just a NodeTest 
    preceded by a ChildOrAttributeAxisSpecifier then the
    priority is -0.5
  + Otherwise the priority is 0.5
 

Returns:

the priority for this PatternExpr

evaluatePredicates

public void evaluatePredicates(NodeSet nodes,
                               XPathContext context)
                        throws XPathException

Evaluates the PredicateExpr of this PathComponent against the given NodeSet and XPathContext.

Parameters:

nodes - the current NodeSet

context - the XPathContext for use during evaluation.

XPathException

getPredicate

public PredicateExpr getPredicate()

Returns the PredicateExpr of this PathComponent

Returns:

the PredicateExpr of this PathComponent

hasPredicates

public boolean hasPredicates()

Returns true if this PathComponent has predicates expressions.

Returns:

true if this PathComponent has predicates expressions.