* Copyright (c) 2007-2012, Oracle and/or its affiliates. All rights reserved.

* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.

*/

/*

* Copyright 1999-2004 The Apache Software Foundation.

*

* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

/*

* $Id: DTMManagerDefault.java,v 1.2.4.1 2005/09/15 08:15:02 suresh_emailid Exp $

*/

* The default implementation for the DTMManager.

*

* %REVIEW% There is currently a reentrancy issue, since the finalizer

* for XRTreeFrag (which runs in the GC thread) wants to call

* DTMManager.release(), and may do so at the same time that the main

* transformation thread is accessing the manager. Our current solution is

* to make most of the manager's methods <code>synchronized</code>.

* Early tests suggest that doing so is not causing a significant

* performance hit in Xalan. However, it should be noted that there

* is a possible alternative solution: rewrite release() so it merely

* posts a request for release onto a threadsafe queue, and explicitly

* process that queue on an infrequent basis during main-thread

* activity (eg, when getDTM() is invoked). The downside of that solution

* would be a greater delay before the DTM's storage is actually released

* for reuse.

* */

  //static final boolean JKESS_XNI_EXPERIMENT=true;

  /** Set this to true if you want a dump of the DTM after creation. */

  private static final boolean DUMPTREE = false;

  /** Set this to true if you want a basic diagnostics. */

  private static final boolean DEBUG = false;

  /**

   * Map from DTM identifier numbers to DTM objects that this manager manages.

   * One DTM may have several prefix numbers, if extended node indexing

   * is in use; in that case, m_dtm_offsets[] will used to control which

   * prefix maps to which section of the DTM.

   *

   * This array grows as necessary; see addDTM().

   *

   * This array grows as necessary; see addDTM(). Growth is uncommon... but

   * access needs to be blindingly fast since it's used in node addressing.

   */

  protected DTM m_dtms[] = new DTM[256];

  /** Map from DTM identifier numbers to offsets. For small DTMs with a

   * single identifier, this will always be 0. In overflow addressing, where

   * additional identifiers are allocated to access nodes beyond the range of

   * a single Node Handle, this table is used to map the handle's node field

   * into the actual node identifier.

   *

   * This array grows as necessary; see addDTM().

   *

   * This array grows as necessary; see addDTM(). Growth is uncommon... but

   * access needs to be blindingly fast since it's used in node addressing.

   * (And at the moment, that includes accessing it from DTMDefaultBase,

   * which is why this is not Protected or Private.)

   */

  int m_dtm_offsets[] = new int[256];

  /**

   * The cache for XMLReader objects to be used if the user did not

   * supply an XMLReader for a SAXSource or supplied a StreamSource.

   */

  protected XMLReaderManager m_readerManager = null;

  /**

   * The default implementation of ContentHandler, DTDHandler and ErrorHandler.

   */

  protected DefaultHandler m_defaultHandler = new DefaultHandler();

  /**

   * Add a DTM to the DTM table. This convenience call adds it as the

   * "base DTM ID", with offset 0. The other version of addDTM should

   * be used if you want to add "extended" DTM IDs with nonzero offsets.

   *

   * @param dtm Should be a valid reference to a DTM.

   * @param id Integer DTM ID to be bound to this DTM

   */

  synchronized public void addDTM(DTM dtm, int id) {    addDTM(dtm,id,0); }

  /**

   * Add a DTM to the DTM table.

   *

   * @param dtm Should be a valid reference to a DTM.

   * @param id Integer DTM ID to be bound to this DTM.

   * @param offset Integer addressing offset. The internal DTM Node ID is

   * obtained by adding this offset to the node-number field of the

   * public DTM Handle. For the first DTM ID accessing each DTM, this is 0;

   * for overflow addressing it will be a multiple of 1<<IDENT_DTM_NODE_BITS.

   */

  synchronized public void addDTM(DTM dtm, int id, int offset)

  {

                if(id>=IDENT_MAX_DTMS)

                {

                        // TODO: %REVIEW% Not really the right error message.

            throw new DTMException(XMLMessages.createXMLMessage(XMLErrorResources.ER_NO_DTMIDS_AVAIL, null)); //"No more DTM IDs are available!");

                }

                // We used to just allocate the array size to IDENT_MAX_DTMS.

                // But we expect to increase that to 16 bits, and I'm not willing

                // to allocate that much space unless needed. We could use one of our

                // handy-dandy Fast*Vectors, but this will do for now.

                // %REVIEW%

                int oldlen=m_dtms.length;

                if(oldlen<=id)

                {

                        // Various growth strategies are possible. I think we don't want

                        // to over-allocate excessively, and I'm willing to reallocate

                        // more often to get that. See also Fast*Vector classes.

                        //

                        // %REVIEW% Should throw a more diagnostic error if we go over the max...

                        int newlen=Math.min((id+256),IDENT_MAX_DTMS);

                        DTM new_m_dtms[] = new DTM[newlen];

                        System.arraycopy(m_dtms,0,new_m_dtms,0,oldlen);

                        m_dtms=new_m_dtms;

                        int new_m_dtm_offsets[] = new int[newlen];

                        System.arraycopy(m_dtm_offsets,0,new_m_dtm_offsets,0,oldlen);

                        m_dtm_offsets=new_m_dtm_offsets;

                }

    m_dtms[id] = dtm;

                m_dtm_offsets[id]=offset;

    dtm.documentRegistration();

                // The DTM should have been told who its manager was when we created it.

                // Do we need to allow for adopting DTMs _not_ created by this manager?

  }

  /**

   * Get the first free DTM ID available. %OPT% Linear search is inefficient!

   */

  synchronized public int getFirstFreeDTMID()

  {

    int n = m_dtms.length;

    for (int i = 1; i < n; i++)

    {

      if(null == m_dtms[i])

      {

        return i;

      }

    }

                return n; // count on addDTM() to throw exception if out of range

  }

  /**

   * The default table for exandedNameID lookups.

   */

  private ExpandedNameTable m_expandedNameTable =

    new ExpandedNameTable();

  /**

   * Constructor DTMManagerDefault

   *

   */

  public DTMManagerDefault(){}

  /**

   * Get an instance of a DTM, loaded with the content from the

   * specified source.  If the unique flag is true, a new instance will

   * always be returned.  Otherwise it is up to the DTMManager to return a

   * new instance or an instance that it already created and may be being used

   * by someone else.

   *

   * A bit of magic in this implementation: If the source is null, unique is true,

   * and incremental and doIndexing are both false, we return an instance of

   * SAX2RTFDTM, which see.

   *

   * (I think more parameters will need to be added for error handling, and entity

   * resolution, and more explicit control of the RTF situation).

   *

   * @param source the specification of the source object.

   * @param unique true if the returned DTM must be unique, probably because it

   * is going to be mutated.

   * @param whiteSpaceFilter Enables filtering of whitespace nodes, and may

   *                         be null.

   * @param incremental true if the DTM should be built incrementally, if

   *                    possible.

   * @param doIndexing true if the caller considers it worth it to use

   *                   indexing schemes.

   *

   * @return a non-null DTM reference.

   */

  synchronized public DTM getDTM(Source source, boolean unique,

                                 DTMWSFilter whiteSpaceFilter,

                                 boolean incremental, boolean doIndexing)

  {

    if(DEBUG && null != source)

      System.out.println("Starting "+

                         (unique ? "UNIQUE" : "shared")+

                         " source: "+source.getSystemId()

                         );

    XMLStringFactory xstringFactory = m_xsf;

    int dtmPos = getFirstFreeDTMID();

    int documentID = dtmPos << IDENT_DTM_NODE_BITS;

    if ((null != source) && source instanceof DOMSource)

    {

      DOM2DTM dtm = new DOM2DTM(this, (DOMSource) source, documentID,

                                whiteSpaceFilter, xstringFactory, doIndexing);

      addDTM(dtm, dtmPos, 0);

      //      if (DUMPTREE)

      //      {

      //        dtm.dumpDTM();

      //      }

      return dtm;

    }

    else

    {

      boolean isSAXSource = (null != source)

        ? (source instanceof SAXSource) : true;

      boolean isStreamSource = (null != source)

        ? (source instanceof StreamSource) : false;

      if (isSAXSource || isStreamSource) {

        XMLReader reader = null;

        SAX2DTM dtm;

        try {

          InputSource xmlSource;

          if (null == source) {

            xmlSource = null;

          } else {

            reader = getXMLReader(source);

            xmlSource = SAXSource.sourceToInputSource(source);

            String urlOfSource = xmlSource.getSystemId();

            if (null != urlOfSource) {

              try {

                urlOfSource = SystemIDResolver.getAbsoluteURI(urlOfSource);

              } catch (Exception e) {

                // %REVIEW% Is there a better way to send a warning?

                System.err.println("Can not absolutize URL: " + urlOfSource);

              }

              xmlSource.setSystemId(urlOfSource);

            }

          }

          if (source==null && unique && !incremental && !doIndexing) {

            // Special case to support RTF construction into shared DTM.

            // It should actually still work for other uses,

            // but may be slightly deoptimized relative to the base

            // to allow it to deal with carrying multiple documents.

            //

            // %REVIEW% This is a sloppy way to request this mode;

            // we need to consider architectural improvements.

            dtm = new SAX2RTFDTM(this, source, documentID, whiteSpaceFilter,

                                 xstringFactory, doIndexing);

          }

          /**************************************************************

          // EXPERIMENTAL 3/22/02

          else if(JKESS_XNI_EXPERIMENT && m_incremental) {

            dtm = new XNI2DTM(this, source, documentID, whiteSpaceFilter,

                              xstringFactory, doIndexing);

          }

          **************************************************************/

          // Create the basic SAX2DTM.

          else {

            dtm = new SAX2DTM(this, source, documentID, whiteSpaceFilter,

                              xstringFactory, doIndexing);

          }

          // Go ahead and add the DTM to the lookup table.  This needs to be

          // done before any parsing occurs. Note offset 0, since we've just

          // created a new DTM.

          addDTM(dtm, dtmPos, 0);

          boolean haveXercesParser =

                     (null != reader)

                     && (reader.getClass()

                               .getName()

                               .equals("com.sun.org.apache.xerces.internal.parsers.SAXParser") );

          if (haveXercesParser) {

            incremental = true;  // No matter what.  %REVIEW%

          }

          // If the reader is null, but they still requested an incremental

          // build, then we still want to set up the IncrementalSAXSource stuff.

          if (m_incremental && incremental

               /* || ((null == reader) && incremental) */) {

            IncrementalSAXSource coParser=null;

            if (haveXercesParser) {

              // IncrementalSAXSource_Xerces to avoid threading.

              try {

                coParser =(IncrementalSAXSource)

                  Class.forName("com.sun.org.apache.xml.internal.dtm.ref.IncrementalSAXSource_Xerces").newInstance();

              }  catch( Exception ex ) {

                ex.printStackTrace();

                coParser=null;

              }

            }

            if (coParser==null ) {

              // Create a IncrementalSAXSource to run on the secondary thread.

              if (null == reader) {

                coParser = new IncrementalSAXSource_Filter();

              } else {

                IncrementalSAXSource_Filter filter =

                         new IncrementalSAXSource_Filter();

                filter.setXMLReader(reader);

                coParser=filter;

              }

            }

            /**************************************************************

            // EXPERIMENTAL 3/22/02

            if (JKESS_XNI_EXPERIMENT && m_incremental &&

                  dtm instanceof XNI2DTM &&

                  coParser instanceof IncrementalSAXSource_Xerces) {

                com.sun.org.apache.xerces.internal.xni.parser.XMLPullParserConfiguration xpc=

                      ((IncrementalSAXSource_Xerces)coParser)

                                           .getXNIParserConfiguration();

              if (xpc!=null) {

                // Bypass SAX; listen to the XNI stream

                ((XNI2DTM)dtm).setIncrementalXNISource(xpc);

              } else {

                  // Listen to the SAX stream (will fail, diagnostically...)

                dtm.setIncrementalSAXSource(coParser);

              }

            } else

            ***************************************************************/

            // Have the DTM set itself up as IncrementalSAXSource's listener.

            dtm.setIncrementalSAXSource(coParser);

            if (null == xmlSource) {

              // Then the user will construct it themselves.

              return dtm;

            }

            if (null == reader.getErrorHandler()) {

              reader.setErrorHandler(dtm);

            }

            reader.setDTDHandler(dtm);

            try {

              // Launch parsing coroutine.  Launches a second thread,

              // if we're using IncrementalSAXSource.filter().

              coParser.startParse(xmlSource);

            } catch (RuntimeException re) {

              dtm.clearCoRoutine();

              throw re;

            } catch (Exception e) {

              dtm.clearCoRoutine();

              throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(e);

            }

          } else {

            if (null == reader) {

              // Then the user will construct it themselves.

              return dtm;

            }

            // not incremental

            reader.setContentHandler(dtm);

            reader.setDTDHandler(dtm);

            if (null == reader.getErrorHandler()) {

              reader.setErrorHandler(dtm);

            }

            try {

              reader.setProperty(

                               "http://xml.org/sax/properties/lexical-handler",

                               dtm);

            } catch (SAXNotRecognizedException e){}

              catch (SAXNotSupportedException e){}

            try {

              reader.parse(xmlSource);

            } catch (RuntimeException re) {

              dtm.clearCoRoutine();

              throw re;

            } catch (Exception e) {

              dtm.clearCoRoutine();

              throw new com.sun.org.apache.xml.internal.utils.WrappedRuntimeException(e);

            }

          }

          if (DUMPTREE) {

            System.out.println("Dumping SAX2DOM");

            dtm.dumpDTM(System.err);

          }

          return dtm;

        } finally {

          // Reset the ContentHandler, DTDHandler, ErrorHandler to the DefaultHandler

          // after creating the DTM.

          if (reader != null && !(m_incremental && incremental)) {

            reader.setContentHandler(m_defaultHandler);

            reader.setDTDHandler(m_defaultHandler);

            reader.setErrorHandler(m_defaultHandler);

            // Reset the LexicalHandler to null after creating the DTM.

            try {

              reader.setProperty("http://xml.org/sax/properties/lexical-handler", null);

            }

            catch (Exception e) {}

          }

          releaseXMLReader(reader);

        }

      } else {

        // It should have been handled by a derived class or the caller

        // made a mistake.

        throw new DTMException(XMLMessages.createXMLMessage(XMLErrorResources.ER_NOT_SUPPORTED, new Object[]{source})); //"Not supported: " + source);

      }

    }

  }

  /**

   * Given a W3C DOM node, try and return a DTM handle.

   * Note: calling this may be non-optimal, and there is no guarantee that

   * the node will be found in any particular DTM.

   *

   * @param node Non-null reference to a DOM node.

   *

   * @return a valid DTM handle.

   */

  synchronized public int getDTMHandleFromNode(org.w3c.dom.Node node)

  {

    if(null == node)

      throw new IllegalArgumentException(XMLMessages.createXMLMessage(XMLErrorResources.ER_NODE_NON_NULL, null)); //"node must be non-null for getDTMHandleFromNode!");

    if (node instanceof com.sun.org.apache.xml.internal.dtm.ref.DTMNodeProxy)

      return ((com.sun.org.apache.xml.internal.dtm.ref.DTMNodeProxy) node).getDTMNodeNumber();

    else

    {

      // Find the DOM2DTMs wrapped around this Document (if any)

      // and check whether they contain the Node in question.

      //

      // NOTE that since a DOM2DTM may represent a subtree rather

      // than a full document, we have to be prepared to check more

      // than one -- and there is no guarantee that we will find

      // one that contains ancestors or siblings of the node we're

      // seeking.

      //

      // %REVIEW% We could search for the one which contains this

      // node at the deepest level, and thus covers the widest

      // subtree, but that's going to entail additional work

      // checking more DTMs... and getHandleOfNode is not a

      // cheap operation in most implementations.

                        //

                        // TODO: %REVIEW% If overflow addressing, we may recheck a DTM

                        // already examined. Ouch. But with the increased number of DTMs,

                        // scanning back to check this is painful.

                        // POSSIBLE SOLUTIONS:

                        //   Generate a list of _unique_ DTM objects?

                        //   Have each DTM cache last DOM node search?

                        int max = m_dtms.length;

      for(int i = 0; i < max; i++)

        {

          DTM thisDTM=m_dtms[i];

          if((null != thisDTM) && thisDTM instanceof DOM2DTM)

          {

            int handle=((DOM2DTM)thisDTM).getHandleOfNode(node);

            if(handle!=DTM.NULL) return handle;

          }

         }

                        // Not found; generate a new DTM.

                        //

                        // %REVIEW% Is this really desirable, or should we return null

                        // and make folks explicitly instantiate from a DOMSource? The

                        // latter is more work but gives the caller the opportunity to

                        // explicitly add the DTM to a DTMManager... and thus to know when

                        // it can be discarded again, which is something we need to pay much

                        // more attention to. (Especially since only DTMs which are assigned

                        // to a manager can use the overflow addressing scheme.)

                        //

                        // %BUG% If the source node was a DOM2DTM$defaultNamespaceDeclarationNode

                        // and the DTM wasn't registered with this DTMManager, we will create

                        // a new DTM and _still_ not be able to find the node (since it will

                        // be resynthesized). Another reason to push hard on making all DTMs

                        // be managed DTMs.

                        // Since the real root of our tree may be a DocumentFragment, we need to

      // use getParent to find the root, instead of getOwnerDocument.  Otherwise

      // DOM2DTM#getHandleOfNode will be very unhappy.

      Node root = node;

      Node p = (root.getNodeType() == Node.ATTRIBUTE_NODE) ? ((org.w3c.dom.Attr)root).getOwnerElement() : root.getParentNode();

      for (; p != null; p = p.getParentNode())

      {

        root = p;

      }

      DOM2DTM dtm = (DOM2DTM) getDTM(new javax.xml.transform.dom.DOMSource(root),

                                                                                                                                                 false, null, true, true);

      int handle;

      if(node instanceof com.sun.org.apache.xml.internal.dtm.ref.dom2dtm.DOM2DTMdefaultNamespaceDeclarationNode)

      {

                                // Can't return the same node since it's unique to a specific DTM,

                                // but can return the equivalent node -- find the corresponding

                                // Document Element, then ask it for the xml: namespace decl.

                                handle=dtm.getHandleOfNode(((org.w3c.dom.Attr)node).getOwnerElement());

                                handle=dtm.getAttributeNode(handle,node.getNamespaceURI(),node.getLocalName());

      }

      else

                                handle = ((DOM2DTM)dtm).getHandleOfNode(node);

      if(DTM.NULL == handle)

        throw new RuntimeException(XMLMessages.createXMLMessage(XMLErrorResources.ER_COULD_NOT_RESOLVE_NODE, null)); //"Could not resolve the node to a handle!");

      return handle;

    }

  }

  /**

   * This method returns the SAX2 parser to use with the InputSource

   * obtained from this URI.

   * It may return null if any SAX2-conformant XML parser can be used,

   * or if getInputSource() will also return null. The parser must

   * be free for use (i.e., not currently in use for another parse().

   * After use of the parser is completed, the releaseXMLReader(XMLReader)

   * must be called.

   *

   * @param inputSource The value returned from the URIResolver.

   * @return  a SAX2 XMLReader to use to resolve the inputSource argument.

   *

   * @return non-null XMLReader reference ready to parse.

   */

  synchronized public XMLReader getXMLReader(Source inputSource)

  {

    try

    {

      XMLReader reader = (inputSource instanceof SAXSource)

                         ? ((SAXSource) inputSource).getXMLReader() : null;

      // If user did not supply a reader, ask for one from the reader manager

      if (null == reader) {

        if (m_readerManager == null) {

            m_readerManager = XMLReaderManager.getInstance(super.useServicesMechnism());

        }

        reader = m_readerManager.getXMLReader();

      }

      return reader;

    } catch (SAXException se) {

      throw new DTMException(se.getMessage(), se);

    }

  }

  /**

   * Indicates that the XMLReader object is no longer in use for the transform.

   *

   * Note that the getXMLReader method may return an XMLReader that was

   * specified on the SAXSource object by the application code.  Such a

   * reader should still be passed to releaseXMLReader, but the reader manager

   * will only re-use XMLReaders that it created.

   *

   * @param reader The XMLReader to be released.

   */

  synchronized public void releaseXMLReader(XMLReader reader) {

    if (m_readerManager != null) {

      m_readerManager.releaseXMLReader(reader);

    }

  }

  /**

   * Return the DTM object containing a representation of this node.

   *

   * @param nodeHandle DTM Handle indicating which node to retrieve

   *

   * @return a reference to the DTM object containing this node.

   */

  synchronized public DTM getDTM(int nodeHandle)

  {

    try

    {

      // Performance critical function.

      return m_dtms[nodeHandle >>> IDENT_DTM_NODE_BITS];

    }

    catch(java.lang.ArrayIndexOutOfBoundsException e)

    {

      if(nodeHandle==DTM.NULL)

                                return null;            // Accept as a special case.

      else

                                throw e;                // Programming error; want to know about it.

    }

  }

  /**

   * Given a DTM, find the ID number in the DTM tables which addresses

   * the start of the document. If overflow addressing is in use, other

   * DTM IDs may also be assigned to this DTM.

   *

   * @param dtm The DTM which (hopefully) contains this node.

   *

   * @return The DTM ID (as the high bits of a NodeHandle, not as our

   * internal index), or -1 if the DTM doesn't belong to this manager.

   */

  synchronized public int getDTMIdentity(DTM dtm)

  {

        // Shortcut using DTMDefaultBase's extension hooks

        // %REVIEW% Should the lookup be part of the basic DTM API?

        if(dtm instanceof DTMDefaultBase)

        {

                DTMDefaultBase dtmdb=(DTMDefaultBase)dtm;

                if(dtmdb.getManager()==this)

                        return dtmdb.getDTMIDs().elementAt(0);

                else

                        return -1;

        }

    int n = m_dtms.length;

    for (int i = 0; i < n; i++)

    {

      DTM tdtm = m_dtms[i];

      if (tdtm == dtm && m_dtm_offsets[i]==0)

        return i << IDENT_DTM_NODE_BITS;

    }

    return -1;

  }

  /**

   * Release the DTMManager's reference(s) to a DTM, making it unmanaged.

   * This is typically done as part of returning the DTM to the heap after

   * we're done with it.

   *

   * @param dtm the DTM to be released.

   *

   * @param shouldHardDelete If false, this call is a suggestion rather than an

   * order, and we may not actually release the DTM. This is intended to

   * support intelligent caching of documents... which is not implemented

   * in this version of the DTM manager.

   *

   * @return true if the DTM was released, false if shouldHardDelete was set

   * and we decided not to.

   */

  synchronized public boolean release(DTM dtm, boolean shouldHardDelete)

  {

    if(DEBUG)

    {

      System.out.println("Releasing "+

                         (shouldHardDelete ? "HARD" : "soft")+

                         " dtm="+

                         // Following shouldn't need a nodeHandle, but does...

                         // and doesn't seem to report the intended value

                         dtm.getDocumentBaseURI()

                         );

    }

    if (dtm instanceof SAX2DTM)

    {

      ((SAX2DTM) dtm).clearCoRoutine();

    }

                // Multiple DTM IDs may be assigned to a single DTM.

                // The Right Answer is to ask which (if it supports

                // extension, the DTM will need a list anyway). The

                // Wrong Answer, applied if the DTM can't help us,

                // is to linearly search them all; this may be very

                // painful.

                //

                // %REVIEW% Should the lookup move up into the basic DTM API?

                if(dtm instanceof DTMDefaultBase)

                {

                        com.sun.org.apache.xml.internal.utils.SuballocatedIntVector ids=((DTMDefaultBase)dtm).getDTMIDs();

                        for(int i=ids.size()-1;i>=0;--i)

                                m_dtms[ids.elementAt(i)>>>DTMManager.IDENT_DTM_NODE_BITS]=null;

                }

                else

                {

                        int i = getDTMIdentity(dtm);

                    if (i >= 0)

                        {

                                m_dtms[i >>> DTMManager.IDENT_DTM_NODE_BITS] = null;

                        }

                }

    dtm.documentRelease();

    return true;

  }

  /**

   * Method createDocumentFragment

   *

   *

   * NEEDSDOC (createDocumentFragment) @return

   */

  synchronized public DTM createDocumentFragment()

  {

    try

    {

      DocumentBuilderFactory dbf = FactoryImpl.getDOMFactory(super.useServicesMechnism());

      dbf.setNamespaceAware(true);

      DocumentBuilder db = dbf.newDocumentBuilder();

      Document doc = db.newDocument();

      Node df = doc.createDocumentFragment();

      return getDTM(new DOMSource(df), true, null, false, false);

    }

    catch (Exception e)

    {

      throw new DTMException(e);

    }

  }

  /**

   * NEEDSDOC Method createDTMIterator

   *

   *

   * NEEDSDOC @param whatToShow

   * NEEDSDOC @param filter

   * NEEDSDOC @param entityReferenceExpansion

   *

   * NEEDSDOC (createDTMIterator) @return

   */

  synchronized public DTMIterator createDTMIterator(int whatToShow, DTMFilter filter,

                                       boolean entityReferenceExpansion)

  {

    /** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */

    return null;

  }

  /**

   * NEEDSDOC Method createDTMIterator

   *

   *

   * NEEDSDOC @param xpathString

   * NEEDSDOC @param presolver

   *

   * NEEDSDOC (createDTMIterator) @return

   */

  synchronized public DTMIterator createDTMIterator(String xpathString,

                                       PrefixResolver presolver)

  {

    /** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */

    return null;

  }

  /**

   * NEEDSDOC Method createDTMIterator

   *

   *

   * NEEDSDOC @param node

   *

   * NEEDSDOC (createDTMIterator) @return

   */

  synchronized public DTMIterator createDTMIterator(int node)

  {

    /** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */

    return null;

  }

  /**

   * NEEDSDOC Method createDTMIterator

   *

   *

   * NEEDSDOC @param xpathCompiler

   * NEEDSDOC @param pos

   *

   * NEEDSDOC (createDTMIterator) @return

   */

  synchronized public DTMIterator createDTMIterator(Object xpathCompiler, int pos)

  {

    /** @todo: implement this com.sun.org.apache.xml.internal.dtm.DTMManager abstract method */

    return null;

  }

  /**

   * return the expanded name table.

   *

   * NEEDSDOC @param dtm

   *

   * NEEDSDOC ($objectName$) @return

   */

  public ExpandedNameTable getExpandedNameTable(DTM dtm)

  {

    return m_expandedNameTable;

  }

}