Java XPath Create getXPath(Element rootElement, Element targetElement, boolean includeElementIndex, Map namespacesMap)

Description

Returns the XPath to retrieve targetElement from rootElement.

License

Open Source License

Parameter

Parameter	Description
includeElementIndex	Indicates if the element indices in the form elementName[n] should be included in the XPath.
namespacesMap	Maps namespace ids to namespace URIs.

Declaration

public static String getXPath(Element rootElement, Element targetElement, boolean includeElementIndex,
        Map<String, String> namespacesMap) 

Method Source Code

//package com.java2s;
/*/*from  w  w  w  .  j  a  v  a  2s.  co m*/
 *  RapidMiner
 *
 *  Copyright (C) 2001-2014 by RapidMiner and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapidminer.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */

import java.util.HashMap;

import java.util.Map;
import java.util.Map.Entry;

import java.util.Stack;

import org.w3c.dom.Element;

import org.w3c.dom.Node;

public class Main {
    /**
     * Returns the XPath to retrieve targetElement from rootElement. rootElement may be null, in this case the XPath starts with and includes
     * the farthest non-null ancestor of targetElement. If rootElement == targetElement, an empty string
     * is returned. 
     * @param includeElementIndex Indicates if the element indices in the form elementName[n] should
     * be included in the XPath. 
     * @param namespacesMap Maps namespace ids to namespace URIs.
     */
    public static String getXPath(Element rootElement, Element targetElement, boolean includeElementIndex,
            Map<String, String> namespacesMap) {
        Stack<Element> elementPath = new Stack<Element>();

        // since we need the mapping the other way round, we invert the map
        Map<String, String> namespaceUriToIdMap = new HashMap<String, String>();
        for (Entry<String, String> entry : namespacesMap.entrySet()) {
            namespaceUriToIdMap.put(entry.getValue(), entry.getKey());
        }

        // recursively find all ancestors of targetElement (up to, not including, rootElement) 
        {
            Element currentElement = targetElement;
            while (currentElement != null && currentElement != rootElement) {
                elementPath.push(currentElement);
                Node parent = currentElement.getParentNode();
                if (parent instanceof Element) {
                    currentElement = (Element) currentElement.getParentNode();
                } else {
                    currentElement = null;
                }
            }
        }

        // construct XPath
        StringBuilder builder = new StringBuilder();
        while (!elementPath.isEmpty()) {
            Element currentElement = elementPath.pop();
            if (builder.length() > 0) {
                // don't include "/" at the beginning
                builder.append("/");
            }

            if (namespacesMap != null) {
                String namespace = currentElement.getNamespaceURI();
                if (namespace != null) {
                    namespace = namespaceUriToIdMap.get(namespace);
                    builder.append(namespace);
                    builder.append(":");
                }
            }
            builder.append(currentElement.getLocalName());
            if (includeElementIndex) {
                int index = getElementIndex(currentElement);
                builder.append("[");
                builder.append(index);
                builder.append("]");
            }
        }
        return builder.toString();
    }

    /**
     * Returns the index of element in the list of all elements with the same name in its parent node.
     * If element's parent node is null, this function returns 0.
     */
    public static int getElementIndex(Element element) {
        int index = 1;
        Node sibling = element;
        while ((sibling = sibling.getPreviousSibling()) != null) {
            if (sibling instanceof Element) {
                Element siblingElement = (Element) sibling;

                // check if element names and element namespaces match 
                if (element.getLocalName().equals(siblingElement.getLocalName())
                        && (element.getNamespaceURI() == null ? siblingElement.getNamespaceURI() == null
                                : element.getNamespaceURI().equals(siblingElement.getNamespaceURI()))) {
                    ++index;
                }
            }
        }
        return index;
    }
}

Related

1. getXpath()
2. getXPath()
3. getxPath()
4. getXPath()
5. getXPath(Element elt)
6. getXPath(NamespaceContext nsContext)
7. getXPath(Node n)
8. getXPath(Node n)
9. getXPath(Node n)