domhelper.java

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            break;
          }

          found2 = true;
        }

        child = child.getNextSibling();
      }
    }

    return isNodeAfterSibling;
  }  // end isNodeAfterSibling(Node parent, Node child1, Node child2)

  //==========================================================
  // SECTION: Namespace resolution
  //==========================================================

  /**
   * Get the depth level of this node in the tree (equals 1 for
   * a parentless node).
   *
   * @param n Node to be examined.
   * @return the number of ancestors, plus one
   * @xsl.usage internal
   */
  public short getLevel(Node n)
  {

    short level = 1;

    while (null != (n = getParentOfNode(n)))
    {
      level++;
    }

    return level;
  }

  /**
   * Given an XML Namespace prefix and a context in which the prefix
   * is to be evaluated, return the Namespace Name this prefix was 
   * bound to. Note that DOM Level 3 is expected to provide a version of
   * this which deals with the DOM's "early binding" behavior.
   * 
   * Default handling:
   *
   * @param prefix String containing namespace prefix to be resolved, 
   * without the ':' which separates it from the localname when used 
   * in a Node Name. The empty sting signifies the default namespace
   * at this point in the document.
   * @param namespaceContext Element which provides context for resolution.
   * (We could extend this to work for other nodes by first seeking their
   * nearest Element ancestor.)
   *
   * @return a String containing the Namespace URI which this prefix
   * represents in the specified context.
   */
  public String getNamespaceForPrefix(String prefix, Element namespaceContext)
  {

    int type;
    Node parent = namespaceContext;
    String namespace = null;

    if (prefix.equals("xml"))
    {
      namespace = QName.S_XMLNAMESPACEURI; // Hardcoded, per Namespace spec
    }
        else if(prefix.equals("xmlns"))
    {
          // Hardcoded in the DOM spec, expected to be adopted by
          // Namespace spec. NOTE: Namespace declarations _must_ use
          // the xmlns: prefix; other prefixes declared as belonging
          // to this namespace will not be recognized and should
          // probably be rejected by parsers as erroneous declarations.
      namespace = "http://www.w3.org/2000/xmlns/"; 
    }
    else
    {
          // Attribute name for this prefix's declaration
          String declname=(prefix=="")
                        ? "xmlns"
                        : "xmlns:"+prefix;
                                           
          // Scan until we run out of Elements or have resolved the namespace
      while ((null != parent) && (null == namespace)
             && (((type = parent.getNodeType()) == Node.ELEMENT_NODE)
                 || (type == Node.ENTITY_REFERENCE_NODE)))
      {
        if (type == Node.ELEMENT_NODE)
        {
                        
                        // Look for the appropriate Namespace Declaration attribute,
                        // either "xmlns:prefix" or (if prefix is "") "xmlns".
                        // TODO: This does not handle "implicit declarations"
                        // which may be created when the DOM is edited. DOM Level
                        // 3 will define how those should be interpreted. But
                        // this issue won't arise in freshly-parsed DOMs.
                        
                // NOTE: declname is set earlier, outside the loop.
                        Attr attr=((Element)parent).getAttributeNode(declname);
                        if(attr!=null)
                        {
                namespace = attr.getNodeValue();
                break;
                        }
                }

        parent = getParentOfNode(parent);
      }
    }

    return namespace;
  }

  /**
   * An experiment for the moment.
   */
  Hashtable m_NSInfos = new Hashtable();

  /** Object to put into the m_NSInfos table that tells that a node has not been 
   *  processed, but has xmlns namespace decls.  */
  protected static final NSInfo m_NSInfoUnProcWithXMLNS = new NSInfo(false,
                                                            true);

  /** Object to put into the m_NSInfos table that tells that a node has not been 
   *  processed, but has no xmlns namespace decls.  */
  protected static final NSInfo m_NSInfoUnProcWithoutXMLNS = new NSInfo(false,
                                                               false);

  /** Object to put into the m_NSInfos table that tells that a node has not been 
   *  processed, and has no xmlns namespace decls, and has no ancestor decls.  */
  protected static final NSInfo m_NSInfoUnProcNoAncestorXMLNS =
    new NSInfo(false, false, NSInfo.ANCESTORNOXMLNS);

  /** Object to put into the m_NSInfos table that tells that a node has been 
   *  processed, and has xmlns namespace decls.  */
  protected static final NSInfo m_NSInfoNullWithXMLNS = new NSInfo(true,
                                                          true);

  /** Object to put into the m_NSInfos table that tells that a node has been 
   *  processed, and has no xmlns namespace decls.  */
  protected static final NSInfo m_NSInfoNullWithoutXMLNS = new NSInfo(true,
                                                             false);

  /** Object to put into the m_NSInfos table that tells that a node has been 
   *  processed, and has no xmlns namespace decls. and has no ancestor decls.  */
  protected static final NSInfo m_NSInfoNullNoAncestorXMLNS =
    new NSInfo(true, false, NSInfo.ANCESTORNOXMLNS);

  /** Vector of node (odd indexes) and NSInfos (even indexes) that tell if 
   *  the given node is a candidate for ancestor namespace processing.  */
  protected Vector m_candidateNoAncestorXMLNS = new Vector();

  /**
   * Returns the namespace of the given node. Differs from simply getting
   * the node's prefix and using getNamespaceForPrefix in that it attempts
   * to cache some of the data in NSINFO objects, to avoid repeated lookup.
   * TODO: Should we consider moving that logic into getNamespaceForPrefix?
   *
   * @param n Node to be examined.
   *
   * @return String containing the Namespace Name (uri) for this node.
   * Note that this is undefined for any nodes other than Elements and
   * Attributes.
   */
  public String getNamespaceOfNode(Node n)
  {

    String namespaceOfPrefix;
    boolean hasProcessedNS;
    NSInfo nsInfo;
    short ntype = n.getNodeType();

    if (Node.ATTRIBUTE_NODE != ntype)
    {
      Object nsObj = m_NSInfos.get(n);  // return value

      nsInfo = (nsObj == null) ? null : (NSInfo) nsObj;
      hasProcessedNS = (nsInfo == null) ? false : nsInfo.m_hasProcessedNS;
    }
    else
    {
      hasProcessedNS = false;
      nsInfo = null;
    }

    if (hasProcessedNS)
    {
      namespaceOfPrefix = nsInfo.m_namespace;
    }
    else
    {
      namespaceOfPrefix = null;

      String nodeName = n.getNodeName();
      int indexOfNSSep = nodeName.indexOf(':');
      String prefix;

      if (Node.ATTRIBUTE_NODE == ntype)
      {
        if (indexOfNSSep > 0)
        {
          prefix = nodeName.substring(0, indexOfNSSep);
        }
        else
        {

          // Attributes don't use the default namespace, so if 
          // there isn't a prefix, we're done.
          return namespaceOfPrefix;
        }
      }
      else
      {
        prefix = (indexOfNSSep >= 0)
                 ? nodeName.substring(0, indexOfNSSep) : "";
      }

      boolean ancestorsHaveXMLNS = false;
      boolean nHasXMLNS = false;

      if (prefix.equals("xml"))
      {
        namespaceOfPrefix = QName.S_XMLNAMESPACEURI;
      }
      else
      {
        int parentType;
        Node parent = n;

        while ((null != parent) && (null == namespaceOfPrefix))
        {
          if ((null != nsInfo)
                  && (nsInfo.m_ancestorHasXMLNSAttrs
                      == NSInfo.ANCESTORNOXMLNS))
          {
            break;
          }

          parentType = parent.getNodeType();

          if ((null == nsInfo) || nsInfo.m_hasXMLNSAttrs)
          {
            boolean elementHasXMLNS = false;

            if (parentType == Node.ELEMENT_NODE)
            {
              NamedNodeMap nnm = parent.getAttributes();

              for (int i = 0; i < nnm.getLength(); i++)
              {
                Node attr = nnm.item(i);
                String aname = attr.getNodeName();

                if (aname.charAt(0) == 'x')
                {
                  boolean isPrefix = aname.startsWith("xmlns:");

                  if (aname.equals("xmlns") || isPrefix)
                  {
                    if (n == parent)
                      nHasXMLNS = true;

                    elementHasXMLNS = true;
                    ancestorsHaveXMLNS = true;

                    String p = isPrefix ? aname.substring(6) : "";

                    if (p.equals(prefix))
                    {
                      namespaceOfPrefix = attr.getNodeValue();

                      break;
                    }
                  }
                }
              }
            }

            if ((Node.ATTRIBUTE_NODE != parentType) && (null == nsInfo)
                    && (n != parent))
            {
              nsInfo = elementHasXMLNS
                       ? m_NSInfoUnProcWithXMLNS : m_NSInfoUnProcWithoutXMLNS;

              m_NSInfos.put(parent, nsInfo);
            }
          }

          if (Node.ATTRIBUTE_NODE == parentType)
          {
            parent = getParentOfNode(parent);
          }
          else
          {
            m_candidateNoAncestorXMLNS.addElement(parent);
            m_candidateNoAncestorXMLNS.addElement(nsInfo);

            parent = parent.getParentNode();
          }

          if (null != parent)
          {
            Object nsObj = m_NSInfos.get(parent);  // return value

            nsInfo = (nsObj == null) ? null : (NSInfo) nsObj;
          }
        }

        int nCandidates = m_candidateNoAncestorXMLNS.size();

        if (nCandidates > 0)
        {
          if ((false == ancestorsHaveXMLNS) && (null == parent))
          {
            for (int i = 0; i < nCandidates; i += 2)
            {
              Object candidateInfo = m_candidateNoAncestorXMLNS.elementAt(i
                                       + 1);

              if (candidateInfo == m_NSInfoUnProcWithoutXMLNS)
              {
                m_NSInfos.put(m_candidateNoAncestorXMLNS.elementAt(i),
                              m_NSInfoUnProcNoAncestorXMLNS);
              }
              else if (candidateInfo == m_NSInfoNullWithoutXMLNS)
              {
                m_NSInfos.put(m_candidateNoAncestorXMLNS.elementAt(i),
                              m_NSInfoNullNoAncestorXMLNS);
              }
            }
          }

          m_candidateNoAncestorXMLNS.removeAllElements();
        }
      }

      if (Node.ATTRIBUTE_NODE != ntype)
      {
        if (null == namespaceOfPrefix)
        {
          if (ancestorsHaveXMLNS)
          {
            if (nHasXMLNS)
              m_NSInfos.put(n, m_NSInfoNullWithXMLNS);
            else
              m_NSInfos.put(n, m_NSInfoNullWithoutXMLNS);
          }
          else
          {
            m_NSInfos.put(n, m_NSInfoNullNoAncestorXMLNS);
          }
        }
        else
        {
          m_NSInfos.put(n, new NSInfo(namespaceOfPrefix, nHasXMLNS));
        }
      }
    }

    return namespaceOfPrefix;
  }

  /**
   * Returns the local name of the given node. If the node's name begins
   * with a namespace prefix, this is the part after the colon; otherwise
   * it's the full node name.
   *
   * @param n the node to be examined.
   *
   * @return String containing the Local Name
   */
  public String getLocalNameOfNode(Node n)
  {

    String qname = n.getNodeName();
    int index = qname.indexOf(':');

    return (index < 0) ? qname : qname.substring(index + 1);
  }

  /**
   * Returns the element name with the namespace prefix (if any) replaced
   * by the Namespace URI it was bound to. This is not a standard 
   * representation of a node name, but it allows convenient 
   * single-string comparison of the "universal" names of two nodes.
   *
   * @param elem Element to be examined.
   *
   * @return String in the form "namespaceURI:localname" if the node
   * belongs to a namespace, or simply "localname" if it doesn't.
   * @see #getExpandedAttributeName
   */
  public String getExpandedElementName(Element elem)
  {

    String namespace = getNamespaceOfNode(elem);

    return (null != namespace)
           ? namespace + ":" + getLocalNameOfNode(elem)
           : getLocalNameOfNode(elem);
  }

  /**
   * Returns the attribute name with the namespace prefix (if any) replaced
   * by the Namespace URI it was bound to. This is not a standard 
   * representation of a node name, but it allows convenient 
   * single-string comparison of the "universal" names of two nodes.
   *
   * @param attr Attr to be examined
   *
   * @return String in the form "namespaceURI:localname" if the node
   * belongs to a namespace, or simply "localname" if it doesn't.
   * @see #getExpandedElementName
   */
  public String getExpandedAttributeName(Attr attr)
  {

    String namespace = getNamespaceOfNode(attr);

    return (null != namespace)
           ? namespace + ":" + getLocalNameOfNode(attr)
           : getLocalNameOfNode(attr);
  }

  //==========================================================
  // SECTION: DOM Helper Functions
  //==========================================================

  /**
   * Tell if the node is ignorable whitespace. Note that this can
   * be determined only in the context of a DTD or other Schema,
   * and that DOM Level 2 has nostandardized DOM API which can
   * return that information.
   * @deprecated
   *
   * @param node Node to be examined
   *
   * @return CURRENTLY HARDCODED TO FALSE, but should return true if
   * and only if the node is of type Text, contains only whitespace,
   * and does not appear as part of the #PCDATA content of an element.
   * (Note that determining this last may require allowing for 
   * Entity References.)
   */