com.hp.hpl.sparta.xpath

Class XPath

java.lang.Object

com.hp.hpl.sparta.xpath.XPath

public class XPath
extends Object

The root of the parse tree for an XPath expression. This is a participant in the Visitor Pattern [Gamma et al, #331]. You create an XPath object (which parses an XPath expression into a parse tree), create a Vistor object, and pass the visitor to the XPath.accept method.

Copyright (C) 2002 Hewlett-Packard Company. This file is part of Sparta, an XML Parser, DOM, and XPath library. This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Version:

$Date: 2003/07/18 00:01:42 $ $Revision: 1.10 $

Author:

Eamonn O'Brien-Strain

Method Summary

Methods

Modifier and Type	Method and Description
Object	clone() A one-level clone in which the steps list is cloned but not the steps objects themselves.
static XPath	get(boolean isAbsolute, Step[] steps) Create an XPath from some steps.
static XPath	get(String xpathString) Return the xpath parse-tree object for this expression.
String	getIndexingAttrName() Return the attribute name in a trailing [@attrName] predicate.
String	getIndexingAttrNameOfEquals() Return the attribute name in a trailing [@attrName='attrValue'] predicate or null if it someother type of predicate..
Enumeration	getSteps()
boolean	isAbsolute() Does this path begin with a '/' or '//' ?
boolean	isStringValue() Does xpath evaluate to a string values (attribute values or text() nodes)
static boolean	isStringValue(String xpathString) Convenience function equivalent to get(xpathString).isStringValue()
String	toString()

Methods inherited from class java.lang.Object

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

Method Detail

toString

public String toString()

Overrides:

toString in class Object

isAbsolute

public boolean isAbsolute()

Does this path begin with a '/' or '//' ?

isStringValue

public boolean isStringValue()

Does xpath evaluate to a string values (attribute values or text() nodes)

getSteps

public Enumeration getSteps()

getIndexingAttrName

public String getIndexingAttrName()
                           throws XPathException

Return the attribute name in a trailing [@attrName] predicate. For example if the Xpath expression was "/a/b[@p='pp']/c[@q]" then the indexing attribute name would be "q"

Throws:

XPathException

getIndexingAttrNameOfEquals

public String getIndexingAttrNameOfEquals()
                                   throws XPathException

Return the attribute name in a trailing [@attrName='attrValue'] predicate or null if it someother type of predicate.. For example if the Xpath expression was "/a/b[@p='pp']/c[@q='qqq']" then the indexing attribute name would be "q"

Throws:

XPathException

clone

public Object clone()

A one-level clone in which the steps list is cloned but not the steps objects themselves. It is OK for different XPaths to share Steps because they are immutable.

Overrides:

clone in class Object

get

public static XPath get(String xpathString)
                 throws XPathException

Return the xpath parse-tree object for this expression. This may be either a newly created object or a cached copy.

Throws:

XPathException

get

public static XPath get(boolean isAbsolute,
        Step[] steps)

Create an XPath from some steps. The value of steps.length must be >= 1

isStringValue

public static boolean isStringValue(String xpathString)
                             throws XPathException,
                                    IOException

Convenience function equivalent to get(xpathString).isStringValue()

Throws:

XPathException

IOException