xpathapi.java

j2me sip客户端程序源码 提供了J2ME中SIP协议开发样例源码

/**
 * @(#)$RCSfile: XPathAPI.java,v $            $Revision: 1.2 $
 *
 * ====================================================================
 * Copyright 2001, Reaxion Corp.,
 * 11418 105th PL NE, Kirkland, WA, 98033, USA
 * All rights reserved.
 * ====================================================================
 *
 * The contents of this file are subject to the Mozilla Public
 * License Version 1.1 (the "License"); you may not use this file
 * except in compliance with the License. You may obtain a copy of
 * the License at http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * The Original Code is the Tequila SyncML.
 *
 * The Initial Developer of the Original Code is Reaxion Corp.
 * All Rights Reserved.
 */
package com.reaxion.tequila.syncml.xml.node.xpath;

import java.util.*;

import org.kxml.kdom.*;

import com.reaxion.tequila.syncml.xml.*;
import com.reaxion.tequila.syncml.xml.node.*;
import com.reaxion.tequila.syncml.util.*;
/**
 * This class is responsible for finding a node in whole XML document
 * using UID with name "NAME" and unique value per document
 *
 * @version   $1.0$
 * @author    Oleg A. Oksyuk
 */
public class XPathAPI
{
    private final static String UID = "UID";

    /**
     * Finds child element of contextNode with attribute "NAME" equals str
     *
     * return   a found node or null if there is no child with such UID
     */
    private static IXMLNode getUID(IXMLNode contextNode, String str)
    {
//        Log.println("  getUID("+contextNode.getAttribute(UID).getValue()+")");
        if (str.equals(contextNode.getAttribute(UID).getValue())) {
            return contextNode;
        }
        Enumeration en = contextNode.getChildren();
        IXMLNode res = null;
        IXMLNode child;
        while (en.hasMoreElements()) {
            child = (IXMLNode) en.nextElement();
            res = getUID(child, str);
            if (null != res) {
                 return res;
            }
        }
        return null;
    }

    /**
     * Finds node or atribute in the document.
     *
     * @param contextNode   root to find in. It could be an instance of class
     *                      Document
     * @param str           path in format: UID or UID?AttributeName
     * @return              found node or attribute
     *
     * @exception           util.XMLDocStructureException if can not find
     *                      a node or attribute
     */
    public static IXMLNodeAttr selectSingleXmlNode(IXMLNode contextNode, String str)
    {
        Log.println("selectSingleXmlNode("+contextNode.getAttribute(UID).getValue()+")");
        int n = str.indexOf("?");
        String uidName;
        String attrName;
        if (n < 0) {
            uidName = str;
            attrName = null;
        } else {
            uidName = str.substring(0, n);
            attrName = str.substring(n+1);
        }
        IXMLNode uid = getUID(contextNode, uidName);
        Log.println("uid=("+uid+")");
        if (null == uid) {
            throw new XMLDocStructureException("Can not find node with UID="+uidName);
        }
        if (null == attrName) {
            return uid;
        }
        IXMLAttr attr = uid.getAttribute(attrName);
        Log.println("attr=("+attr+")");
        if (null == attr) {
            throw new XMLDocStructureException("Node with UID="+uidName+" has no attribute "+attrName);
        }
        return attr;
    }
}

/* -----------------------------------------------------------------------------
 * Change log:
 * -----------------------------------------------------------------------------
 * $Log: XPathAPI.java,v $
 * Revision 1.2  2001/10/17 15:27:43  OlegO
 * changed comments for better javadoc
 *
 * Revision 1.1.1.1  2001/10/11 13:13:32  OlegO
 * no message
 *
 * Revision 1.1  2001/07/27 07:46:16  OlegO
 * no message
 *
 */