XML Server Getting Started    

Appendix C : XPathAPI   Helper Class used in this tutorial 

package com.cti.xmlsp; 

import org.xml.sax.SAXException; 

import org.w3c.dom.Node; 

import org.w3c.dom.Document; 

import org.w3c.dom.NodeList; 

import org.apache.xalan.xpath.XPathSupport; 

import org.apache.xalan.xpath.XPath; 

import org.apache.xalan.xpath.XPathProcessorImpl; 

import org.apache.xalan.xpath.xml.XMLParserLiaisonDefault; 

import org.apache.xalan.xpath.xml.PrefixResolverDefault; 

import org.apache.xalan.xpath.XObject; 

public class XPathAPI 

{ 

   public XPathAPI() 

  { 

    _xpathSupport = new XMLParserLiaisonDefault(); 

    _xpath = new XPath(); 

    _xpathProcessor = new XPathProcessorImpl(_xpathSupport); 

  } 

  public void setPrefixResolver(Node contextNode, Node namespaceNode) { 

    if(null == namespaceNode) namespaceNode = contextNode; 

 _prefixResolver = new PrefixResolverDefault((namespaceNode.getNodeType() == Node.DOCUMENT_NODE) 

                                                         ? ((Document)namespaceNode).getDocumentElement() : 

                                                           namespaceNode); 

  } 

  public void setPrefixResolver(Node contextNode) { 

 setPrefixResolver(contextNode, contextNode);    

  } 

 /** 

   * Use an XPath string to select a single node. XPath namespace 

   * prefixes are resolved from the context node, which may not 

   * be what you want (see the next method). 

   * 

   * @param contextNode The node to start searching from. 

   * @param str A valid XPath string. 

   * @return The first node found that matches the XPath, or null. 

   */ 

  public Node selectSingleNode(Node contextNode, String str) 

    throws SAXException 

  { 

    return selectSingleNode(contextNode, str, contextNode); 

  } 

 2000 2002 Computer Technology Inc. All rights reserved. 

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