org.exolab.adaptx.xpath.expressions
Class UnionExpr

java.lang.Object
  |
  +--org.exolab.adaptx.xpath.expressions.UnionExpr

All Implemented Interfaces:

MatchExpression, XPathExpression

public abstract class UnionExpr

extends java.lang.Object

implements XPathExpression, MatchExpression

An abstract class that represents an XPath Union expression

 UnionExpr ::= PathExpr | (PathExpr '|' UnionExpr)
 

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

Constructor Summary

UnionExpr()

Method Summary

short	getExprType() Returns the type of Expr this Expr represents
PathExpr	getMatchingExpr(XPathNode node, XPathContext context) Retrieves the PathExpr that matches the given node.
abstract PathExpr	getPathExpr() Returns the PathExpr of this UnionExpr.
abstract UnionExpr	getUnionExpr() Returns the UnionExpr that this UnionExpr is in union with.
abstract boolean	matches(XPathNode node, XPathContext context) Determines if the given node is matched by this MatchExpr with respect to the given context.

Methods inherited from class java.lang.Object

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

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

evaluate, toString

Constructor Detail

UnionExpr

public UnionExpr()

Method Detail

getPathExpr

public abstract PathExpr getPathExpr()

Returns the PathExpr of this UnionExpr. A UnionExpr is defined by XPath 1.0 as:

 UnionExpr ::= PathExpr | (PathExpr '|' UnionExpr)
 

Returns:

the PathExpr of this UnionExpr.

getUnionExpr

public abstract UnionExpr getUnionExpr()

Returns the UnionExpr that this UnionExpr is in union with. A UnionExpr is defined by XPath 1.0 as:

 UnionExpr ::= PathExpr | (PathExpr '|' UnionExpr)
 

Returns:

the UnionExpr that this UnionExpr is in union with, or null if this is UnionExpr only contains a PathExpr.

See Also:

getPathExpr()

getExprType

public final short getExprType()

Returns the type of Expr this Expr represents

Specified by:

getExprType in interface XPathExpression

Returns:

the type of Expr this Expr represents

getMatchingExpr

public PathExpr getMatchingExpr(XPathNode node,
                                XPathContext context)
                         throws XPathException

Retrieves the PathExpr that matches the given node. If more than one PathExpr matches the given node, the most specific PathExpr will be returned.

Parameters:

node - the node to test for matching

Returns:

the matching PathExpr or null if none match

XPathException

matches

public abstract boolean matches(XPathNode node,
                                XPathContext context)
                         throws XPathException

Determines if the given node is matched by this MatchExpr with respect to the given context.

Specified by:

matches in interface MatchExpression

Parameters:

node - the node to determine a match for

context - the XPathContext

Returns:

true if the given node is matched by this MatchExpr

Throws:

XPathException - when an error occurs during evaluation