Class IDIndexer

java.lang.Object
org.exolab.adaptx.xml.IDIndexer
public class IDIndexer extends Object
A utility class which helps overcome some DOM 1.0 deficiencies.
Version:
$Revision: 3633 $ $Date: 2003-03-01 08:38:44 +0100 (Sat, 01 Mar 2003) $
Author:
Keith Visco

  • Constructor Details

    • IDIndexer

      public IDIndexer()
      Creates a new DOMHelper

  • Method Details

    • addIdAttribute

      public void addIdAttribute(String attrName, String appliesTo)
      Adds the given attribute name as an ID attribute.
      Parameters:
      attrName - the name of the attribute to treat as an Id.
      appliesTo - the element that this ID attribute appliesTo, "*" may be used to indicate all Elements.

    • addIdReference

      public void addIdReference(String id, XPathNode node)
      Associates the given Id with the given Element
      Parameters:
      id - the Id to associate with the given Element
      element - the element which the Id maps to

    • getElementById

      public XPathNode getElementById(XPathNode root, String id)
      Determines the document order of a given node. Document Order is defined by the document order of the parent of the given node and the childNumber of the given Node. The document order for a Document node is 0.
      Parameters:
      root - the "root" XPathNode to search within
      id - the Id of the element to return
      Returns:
      the element XPathNode that is associated with the given Id, or null if no XPathNode was found
      See Also:
      • invalid reference 
        public int[] getDocumentOrder(Node node) {

       int[] order = null;

       if (node == null) {
           order = new int[1];
           order[0] = -1;
           return order;
       }

       //-- check cache
       //-- * due to bugs in XML4J 1.1.x (2.x works fine) 
       //-- * we need to use the System.identityHash to
       //-- * create a unique key. The problem is Attr nodes
       //-- * with the same name, generate the same hash code.
       Object key = createKey(node);

       order = (int[]) documentOrders.get(key);
       if (order != null) return order;


       Node parent = null;
       //-- calculate document order
       if (node.getNodeType() == Node.ATTRIBUTE_NODE) {
           // Use parent's document order for attributes
           parent = getParentNode((Attr)node);
           if (parent == null) {
               // int[3]  {0 = document, 0 = att-list, att-number}
               order = new int[3];
               order[0] = 0;
               order[1] = 0;
               order[2] = childNumber(node);
           }
           else { 
               int[] porder = getDocumentOrder(parent);
               order = new int[porder.length+2];
               for (int i = 0; i invalid input: '<' porder.length; i++) 
                   order[i] = porder[i];
               order[order.length-2] = 0;  //-- signal att-list
               order[order.length-1] = childNumber(node);
           }
       }
       else if (node.getNodeType() == Node.DOCUMENT_NODE) {
           order = new int[1];
           order[0] = 0;
       }
       else {

           //-- get parent's document order
           parent = getParentNode(node);
           int[] porder = getDocumentOrder(getParentNode(node));
           order = new int[porder.length+1];
           for (int i = 0; i invalid input: '<' porder.length; i++) 
               order[i] = porder[i];
           order[order.length-1] = childNumber(node);
       }

       //-- add to cache
       documentOrders.put(key,order);
       return order;
   } //-- getDocumentOrder

   /**
Returns the element XPathNode that is associated with the given Id.