/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you 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: DTMDefaultBase.java 1225429 2011-12-29 04:44:11Z mrglavas $
 */
package org.apache.xml.dtm.ref;

import org.apache.xml.dtm.*;
import org.apache.xml.utils.SuballocatedIntVector;
import org.apache.xml.utils.BoolStack;

import java.util.Vector;

import javax.xml.transform.Source;

import org.apache.xml.utils.XMLString;
import org.apache.xml.utils.XMLStringFactory;

import org.apache.xml.res.XMLMessages;
import org.apache.xml.res.XMLErrorResources;

import java.io.*; // for dumpDTM

The DTMDefaultBase class serves as a helper base for DTMs.
It sets up structures for navigation and type, while leaving data
management and construction to the derived classes.
/**
 * The <code>DTMDefaultBase</code> class serves as a helper base for DTMs.
 * It sets up structures for navigation and type, while leaving data
 * management and construction to the derived classes.
 */
public abstract class DTMDefaultBase implements DTM
{
    static final boolean JJK_DEBUG=false;

  // This constant is likely to be removed in the future. Use the 
  // getDocument() method instead of ROOTNODE to get at the root 
  // node of a DTM.
  
The identity of the root node. /** The identity of the root node. */
  public static final int ROOTNODE = 0;
	
  
The number of nodes, which is also used to determine the next
 node index.
/**
   * The number of nodes, which is also used to determine the next
   *  node index.
   */
  protected int m_size = 0;

  
The expanded names, one array element for each node. /** The expanded names, one array element for each node. */
  protected SuballocatedIntVector m_exptype;

  
First child values, one array element for each node. /** First child values, one array element for each node. */
  protected SuballocatedIntVector m_firstch;

  
Next sibling values, one array element for each node. /** Next sibling values, one array element for each node. */
  protected SuballocatedIntVector m_nextsib;

  
Previous sibling values, one array element for each node. /** Previous sibling values, one array element for each node. */
  protected SuballocatedIntVector m_prevsib;

  
Previous sibling values, one array element for each node. /** Previous sibling values, one array element for each node. */
  protected SuballocatedIntVector m_parent;

  
Vector of SuballocatedIntVectors of NS decl sets /** Vector of SuballocatedIntVectors of NS decl sets */
  protected Vector m_namespaceDeclSets = null;

  
SuballocatedIntVector  of elements at which corresponding
namespaceDeclSets were defined /** SuballocatedIntVector  of elements at which corresponding
   * namespaceDeclSets were defined */
  protected SuballocatedIntVector m_namespaceDeclSetElements = null;

  
These hold indexes to elements based on namespace and local name.
The base lookup is the the namespace.  The second lookup is the local
name, and the last array contains the the first free element
at the start, and the list of element handles following.
/**
   * These hold indexes to elements based on namespace and local name.
   * The base lookup is the the namespace.  The second lookup is the local
   * name, and the last array contains the the first free element
   * at the start, and the list of element handles following.
   */
  protected int[][][] m_elemIndexes;

  
The default block size of the node arrays /** The default block size of the node arrays */
  public static final int DEFAULT_BLOCKSIZE = 512;  // favor small docs.
  
  
The number of blocks for the node arrays /** The number of blocks for the node arrays */
  public static final int DEFAULT_NUMBLOCKS = 32;
  
  
The number of blocks used for small documents & RTFs /** The number of blocks used for small documents & RTFs */
  public static final int DEFAULT_NUMBLOCKS_SMALL = 4;
  
  /** The block size of the node arrays */
  //protected final int m_blocksize;

  
The value to use when the information has not been built yet.
/**
   * The value to use when the information has not been built yet.
   */
  protected static final int NOTPROCESSED = DTM.NULL - 1;

  
The DTM manager who "owns" this DTM.
/**
   * The DTM manager who "owns" this DTM.
   */

  public DTMManager m_mgr;

  
m_mgr cast to DTMManagerDefault, or null if it isn't an instance
(Efficiency hook)
/**
   * m_mgr cast to DTMManagerDefault, or null if it isn't an instance
   * (Efficiency hook)
   */
  protected DTMManagerDefault m_mgrDefault=null;


  
The document identity number(s). If we have overflowed the addressing
range of the first that was assigned to us, we may add others. /** The document identity number(s). If we have overflowed the addressing
   * range of the first that was assigned to us, we may add others. */
  protected SuballocatedIntVector m_dtmIdent;

  /** The mask for the identity.
      %REVIEW% Should this really be set to the _DEFAULT? What if
      a particular DTM wanted to use another value? */
  //protected final static int m_mask = DTMManager.IDENT_NODE_DEFAULT;

  
The base URI for this document. /** The base URI for this document. */
  protected String m_documentBaseURI;

  
The whitespace filter that enables elements to strip whitespace or not.
/**
   * The whitespace filter that enables elements to strip whitespace or not.
   */
  protected DTMWSFilter m_wsfilter;

  
Flag indicating whether to strip whitespace nodes /** Flag indicating whether to strip whitespace nodes */
  protected boolean m_shouldStripWS = false;

  
Stack of flags indicating whether to strip whitespace nodes /** Stack of flags indicating whether to strip whitespace nodes */
  protected BoolStack m_shouldStripWhitespaceStack;

  
The XMLString factory for creating XMLStrings. /** The XMLString factory for creating XMLStrings. */
  protected XMLStringFactory m_xstrf;

  
The table for exandedNameID lookups.  This may or may not be the same
table as is contained in the DTMManagerDefault.
/**
   * The table for exandedNameID lookups.  This may or may not be the same
   * table as is contained in the DTMManagerDefault.
   */
  protected ExpandedNameTable m_expandedNameTable;

  
true if indexing is turned on. /** true if indexing is turned on. */
  protected boolean m_indexing;

  
Construct a DTMDefaultBase object using the default block size.
Params:
mgr – The DTMManager who owns this DTM.
source – The object that is used to specify the construction source.
dtmIdentity – The DTM identity ID for this DTM.
whiteSpaceFilter – The white space filter for this DTM, which may
                        be null.
xstringfactory – The factory to use for creating XMLStrings.
doIndexing – true if the caller considers it worth it to use
                  indexing schemes./**
   * Construct a DTMDefaultBase object using the default block size.
   *
   * @param mgr The DTMManager who owns this DTM.
   * @param source The object that is used to specify the construction source.
   * @param dtmIdentity The DTM identity ID for this DTM.
   * @param whiteSpaceFilter The white space filter for this DTM, which may
   *                         be null.
   * @param xstringfactory The factory to use for creating XMLStrings.
   * @param doIndexing true if the caller considers it worth it to use
   *                   indexing schemes.
   */
  public DTMDefaultBase(DTMManager mgr, Source source, int dtmIdentity,
  			DTMWSFilter whiteSpaceFilter,
  			XMLStringFactory xstringfactory, boolean doIndexing)
  {
    this(mgr, source, dtmIdentity, whiteSpaceFilter, xstringfactory,
         doIndexing, DEFAULT_BLOCKSIZE, true, false);
  }

  
Construct a DTMDefaultBase object from a DOM node.
Params:
mgr – The DTMManager who owns this DTM.
source – The object that is used to specify the construction source.
dtmIdentity – The DTM identity ID for this DTM.
whiteSpaceFilter – The white space filter for this DTM, which may
                        be null.
xstringfactory – The factory to use for creating XMLStrings.
doIndexing – true if the caller considers it worth it to use
                  indexing schemes.
blocksize – The block size of the DTM.
usePrevsib – true if we want to build the previous sibling node array.
newNameTable – true if we want to use a new ExpandedNameTable for this DTM./**
   * Construct a DTMDefaultBase object from a DOM node.
   *
   * @param mgr The DTMManager who owns this DTM.
   * @param source The object that is used to specify the construction source.
   * @param dtmIdentity The DTM identity ID for this DTM.
   * @param whiteSpaceFilter The white space filter for this DTM, which may
   *                         be null.
   * @param xstringfactory The factory to use for creating XMLStrings.
   * @param doIndexing true if the caller considers it worth it to use
   *                   indexing schemes.
   * @param blocksize The block size of the DTM.
   * @param usePrevsib true if we want to build the previous sibling node array.
   * @param newNameTable true if we want to use a new ExpandedNameTable for this DTM.
   */
  public DTMDefaultBase(DTMManager mgr, Source source, int dtmIdentity,
                        DTMWSFilter whiteSpaceFilter,
                        XMLStringFactory xstringfactory, boolean doIndexing,
                        int blocksize, boolean usePrevsib,
                        boolean newNameTable)
  {    
    // Use smaller sizes for the internal node arrays if the block size
    // is small.
    int numblocks;    
    if (blocksize <= 64)
    {
      numblocks = DEFAULT_NUMBLOCKS_SMALL;
      m_dtmIdent= new SuballocatedIntVector(4, 1);
    }
    else
    {
      numblocks = DEFAULT_NUMBLOCKS;
      m_dtmIdent= new SuballocatedIntVector(32);
    }
    
    m_exptype = new SuballocatedIntVector(blocksize, numblocks);
    m_firstch = new SuballocatedIntVector(blocksize, numblocks);
    m_nextsib = new SuballocatedIntVector(blocksize, numblocks);
    m_parent  = new SuballocatedIntVector(blocksize, numblocks);
    
    // Only create the m_prevsib array if the usePrevsib flag is true.
    // Some DTM implementations (e.g. SAXImpl) do not need this array.
    // We can save the time to build it in those cases.
    if (usePrevsib)
      m_prevsib = new SuballocatedIntVector(blocksize, numblocks);

    m_mgr = mgr;
    if(mgr instanceof DTMManagerDefault)
      m_mgrDefault=(DTMManagerDefault)mgr;
    
    m_documentBaseURI = (null != source) ? source.getSystemId() : null;
    m_dtmIdent.setElementAt(dtmIdentity,0);
    m_wsfilter = whiteSpaceFilter;
    m_xstrf = xstringfactory;
    m_indexing = doIndexing;

    if (doIndexing)
    {
      m_expandedNameTable = new ExpandedNameTable();
    }
    else
    {
      // Note that this fails if we aren't talking to an instance of
      // DTMManagerDefault
      m_expandedNameTable = m_mgrDefault.getExpandedNameTable(this);
    }

    if (null != whiteSpaceFilter)
    {
      m_shouldStripWhitespaceStack = new BoolStack();

      pushShouldStripWhitespace(false);
    }
  }

  
Ensure that the size of the element indexes can hold the information.
Params:
namespaceID – Namespace ID index.
LocalNameID – Local name ID./**
   * Ensure that the size of the element indexes can hold the information.
   *
   * @param namespaceID Namespace ID index.
   * @param LocalNameID Local name ID.
   */
  protected void ensureSizeOfIndex(int namespaceID, int LocalNameID)
  {

    if (null == m_elemIndexes)
    {
      m_elemIndexes = new int[namespaceID + 20][][];
    }
    else if (m_elemIndexes.length <= namespaceID)
    {
      int[][][] indexes = m_elemIndexes;

      m_elemIndexes = new int[namespaceID + 20][][];

      System.arraycopy(indexes, 0, m_elemIndexes, 0, indexes.length);
    }

    int[][] localNameIndex = m_elemIndexes[namespaceID];

    if (null == localNameIndex)
    {
      localNameIndex = new int[LocalNameID + 100][];
      m_elemIndexes[namespaceID] = localNameIndex;
    }
    else if (localNameIndex.length <= LocalNameID)
    {
      int[][] indexes = localNameIndex;

      localNameIndex = new int[LocalNameID + 100][];

      System.arraycopy(indexes, 0, localNameIndex, 0, indexes.length);

      m_elemIndexes[namespaceID] = localNameIndex;
    }

    int[] elemHandles = localNameIndex[LocalNameID];

    if (null == elemHandles)
    {
      elemHandles = new int[128];
      localNameIndex[LocalNameID] = elemHandles;
      elemHandles[0] = 1;
    }
    else if (elemHandles.length <= elemHandles[0] + 1)
    {
      int[] indexes = elemHandles;

      elemHandles = new int[elemHandles[0] + 1024];

      System.arraycopy(indexes, 0, elemHandles, 0, indexes.length);

      localNameIndex[LocalNameID] = elemHandles;
    }
  }

  
Add a node to the element indexes. The node will not be added unless
it's an element.
Params:
expandedTypeID – The expanded type ID of the node.
identity – The node identity index./**
   * Add a node to the element indexes. The node will not be added unless
   * it's an element.
   *
   * @param expandedTypeID The expanded type ID of the node.
   * @param identity The node identity index.
   */
  protected void indexNode(int expandedTypeID, int identity)
  {

    ExpandedNameTable ent = m_expandedNameTable;
    short type = ent.getType(expandedTypeID);

    if (DTM.ELEMENT_NODE == type)
    {
      int namespaceID = ent.getNamespaceID(expandedTypeID);
      int localNameID = ent.getLocalNameID(expandedTypeID);

      ensureSizeOfIndex(namespaceID, localNameID);

      int[] index = m_elemIndexes[namespaceID][localNameID];

      index[index[0]] = identity;

      index[0]++;
    }
  }

  
Find the first index that occurs in the list that is greater than or
equal to the given value.
Params:
list – A list of integers.
start – The start index to begin the search.
len – The number of items to search.
value – Find the slot that has a value that is greater than or
identical to this argument.
Returns:
The index in the list of the slot that is higher or identical
to the identity argument, or -1 if no node is higher or equal./**
   * Find the first index that occurs in the list that is greater than or
   * equal to the given value.
   *
   * @param list A list of integers.
   * @param start The start index to begin the search.
   * @param len The number of items to search.
   * @param value Find the slot that has a value that is greater than or
   * identical to this argument.
   *
   * @return The index in the list of the slot that is higher or identical
   * to the identity argument, or -1 if no node is higher or equal.
   */
  protected int findGTE(int[] list, int start, int len, int value)
  {

    int low = start;
    int high = start + (len - 1);
    int end = high;

    while (low <= high)
    {
      int mid = (low + high) >>> 1;
      int c = list[mid];

      if (c > value)
        high = mid - 1;
      else if (c < value)
        low = mid + 1;
      else
        return mid;
    }

    return (low <= end && list[low] > value) ? low : -1;
  }

  
Find the first matching element from the index at or after the
given node.
Params:
nsIndex – The namespace index lookup.
lnIndex – The local name index lookup.
firstPotential – The first potential match that is worth looking at.
Returns:
The first node that is greater than or equal to the
        firstPotential argument, or DTM.NOTPROCESSED if not found./**
   * Find the first matching element from the index at or after the
   * given node.
   *
   * @param nsIndex The namespace index lookup.
   * @param lnIndex The local name index lookup.
   * @param firstPotential The first potential match that is worth looking at.
   *
   * @return The first node that is greater than or equal to the
   *         firstPotential argument, or DTM.NOTPROCESSED if not found.
   */
  int findElementFromIndex(int nsIndex, int lnIndex, int firstPotential)
  {

    int[][][] indexes = m_elemIndexes;

    if (null != indexes && nsIndex < indexes.length)
    {
      int[][] lnIndexs = indexes[nsIndex];

      if (null != lnIndexs && lnIndex < lnIndexs.length)
      {
        int[] elems = lnIndexs[lnIndex];

        if (null != elems)
        {
          int pos = findGTE(elems, 1, elems[0], firstPotential);

          if (pos > -1)
          {
            return elems[pos];
          }
        }
      }
    }

    return NOTPROCESSED;
  }

  
Get the next node identity value in the list, and call the iterator
if it hasn't been added yet.
Params:
identity – The node identity (index).
Returns:
identity+1, or DTM.NULL./**
   * Get the next node identity value in the list, and call the iterator
   * if it hasn't been added yet.
   *
   * @param identity The node identity (index).
   * @return identity+1, or DTM.NULL.
   */
  protected abstract int getNextNodeIdentity(int identity);

  
This method should try and build one or more nodes in the table.
Returns:
The true if a next node is found or false if
        there are no more nodes./**
   * This method should try and build one or more nodes in the table.
   *
   * @return The true if a next node is found or false if
   *         there are no more nodes.
   */
  protected abstract boolean nextNode();

  
Get the number of nodes that have been added.
Returns:
the number of nodes that have been mapped./**
   * Get the number of nodes that have been added.
   *
   * @return the number of nodes that have been mapped.
   */
  protected abstract int getNumberOfNodes();

  
Stateless axis traversers, lazely built. /** Stateless axis traversers, lazely built. */
  protected DTMAxisTraverser[] m_traversers;

//    /**
//     * Ensure that the size of the information arrays can hold another entry
//     * at the given index.
//     *
//     * @param index On exit from this function, the information arrays sizes must be
//     * at least index+1.
//     */
//    protected void ensureSize(int index)
//    {
//        // We've cut over to Suballocated*Vector, which are self-sizing.
//    }

  
Get the simple type ID for the given node identity.
Params:
identity – The node identity.
Returns:
The simple type ID, or DTM.NULL./**
   * Get the simple type ID for the given node identity.
   *
   * @param identity The node identity.
   *
   * @return The simple type ID, or DTM.NULL.
   */
  protected short _type(int identity)
  {

    int info = _exptype(identity);

    if (NULL != info)
      return m_expandedNameTable.getType(info);
    else
      return NULL;
  }

  
Get the expanded type ID for the given node identity.
Params:
identity – The node identity.
Returns:
The expanded type ID, or DTM.NULL./**
   * Get the expanded type ID for the given node identity.
   *
   * @param identity The node identity.
   *
   * @return The expanded type ID, or DTM.NULL.
   */
  protected int _exptype(int identity)
  {
  	if (identity == DTM.NULL)
  	return NULL;
    // Reorganized test and loop into single flow
    // Tiny performance improvement, saves a few bytes of code, clearer.
    // %OPT% Other internal getters could be treated simliarly
    while (identity>=m_size)
    {
      if (!nextNode() && identity >= m_size)
        return NULL;
    }
    return m_exptype.elementAt(identity);

  }

  
Get the level in the tree for the given node identity.
Params:
identity – The node identity.
Returns:
The tree level, or DTM.NULL./**
   * Get the level in the tree for the given node identity.
   *
   * @param identity The node identity.
   *
   * @return The tree level, or DTM.NULL.
   */
  protected int _level(int identity)
  {
    while (identity>=m_size)
    {
      boolean isMore = nextNode();
      if (!isMore && identity >= m_size)
        return NULL;
    }

    int i=0;
    while(NULL != (identity=_parent(identity)))
      ++i;
    return i;
  }

  
Get the first child for the given node identity.
Params:
identity – The node identity.
Returns:
The first child identity, or DTM.NULL./**
   * Get the first child for the given node identity.
   *
   * @param identity The node identity.
   *
   * @return The first child identity, or DTM.NULL.
   */
  protected int _firstch(int identity)
  {

    // Boiler-plate code for each of the _xxx functions, except for the array.
    int info = (identity >= m_size) ? NOTPROCESSED : m_firstch.elementAt(identity);

    // Check to see if the information requested has been processed, and,
    // if not, advance the iterator until we the information has been
    // processed.
    while (info == NOTPROCESSED)
    {
      boolean isMore = nextNode();

      if (identity >= m_size &&!isMore)
        return NULL;
      else
      {
        info = m_firstch.elementAt(identity);
        if(info == NOTPROCESSED && !isMore)
          return NULL;
      }
    }

    return info;
  }

  
Get the next sibling for the given node identity.
Params:
identity – The node identity.
Returns:
The next sibling identity, or DTM.NULL./**
   * Get the next sibling for the given node identity.
   *
   * @param identity The node identity.
   *
   * @return The next sibling identity, or DTM.NULL.
   */
  protected int _nextsib(int identity)
  {
    // Boiler-plate code for each of the _xxx functions, except for the array.
    int info = (identity >= m_size) ? NOTPROCESSED : m_nextsib.elementAt(identity);

    // Check to see if the information requested has been processed, and,
    // if not, advance the iterator until we the information has been
    // processed.
    while (info == NOTPROCESSED)
    {
      boolean isMore = nextNode();

      if (identity >= m_size &&!isMore)
        return NULL;
      else
      {
        info = m_nextsib.elementAt(identity);
        if(info == NOTPROCESSED && !isMore)
          return NULL;
      }
    }

    return info;
  }

  
Get the previous sibling for the given node identity.
Params:
identity – The node identity.
Returns:
The previous sibling identity, or DTM.NULL./**
   * Get the previous sibling for the given node identity.
   *
   * @param identity The node identity.
   *
   * @return The previous sibling identity, or DTM.NULL.
   */
  protected int _prevsib(int identity)
  {

    if (identity < m_size)
      return m_prevsib.elementAt(identity);

    // Check to see if the information requested has been processed, and,
    // if not, advance the iterator until we the information has been
    // processed.
    while (true)
    {
      boolean isMore = nextNode();

      if (identity >= m_size && !isMore)
        return NULL;
      else if (identity < m_size)
        return m_prevsib.elementAt(identity);
    }
  }

  
Get the parent for the given node identity.
Params:
identity – The node identity.
Returns:
The parent identity, or DTM.NULL./**
   * Get the parent for the given node identity.
   *
   * @param identity The node identity.
   *
   * @return The parent identity, or DTM.NULL.
   */
  protected int _parent(int identity)
  {

    if (identity < m_size)
      return m_parent.elementAt(identity);

    // Check to see if the information requested has been processed, and,
    // if not, advance the iterator until we the information has been
    // processed.
    while (true)
    {
      boolean isMore = nextNode();

      if (identity >= m_size && !isMore)
        return NULL;
      else if (identity < m_size)
        return m_parent.elementAt(identity);
    }
  }

  
Diagnostics function to dump the DTM.
/**
   * Diagnostics function to dump the DTM.
   */
  public void dumpDTM(OutputStream os)
  {
    try
    {
      if(os==null)
      {
	      File f = new File("DTMDump"+((Object)this).hashCode()+".txt");
 	      System.err.println("Dumping... "+f.getAbsolutePath());
 	      os=new FileOutputStream(f);
      }
      PrintStream ps = new PrintStream(os);

      while (nextNode()){}

      int nRecords = m_size;

      ps.println("Total nodes: " + nRecords);

      for (int index = 0; index < nRecords; ++index)
      {
      	int i=makeNodeHandle(index);
        ps.println("=========== index=" + index + " handle=" + i + " ===========");
        ps.println("NodeName: " + getNodeName(i));
        ps.println("NodeNameX: " + getNodeNameX(i));
        ps.println("LocalName: " + getLocalName(i));
        ps.println("NamespaceURI: " + getNamespaceURI(i));
        ps.println("Prefix: " + getPrefix(i));

        int exTypeID = _exptype(index);

        ps.println("Expanded Type ID: "
                           + Integer.toHexString(exTypeID));

        int type = _type(index);
        String typestring;

        switch (type)
        {
        case DTM.ATTRIBUTE_NODE :
          typestring = "ATTRIBUTE_NODE";
          break;
        case DTM.CDATA_SECTION_NODE :
          typestring = "CDATA_SECTION_NODE";
          break;
        case DTM.COMMENT_NODE :
          typestring = "COMMENT_NODE";
          break;
        case DTM.DOCUMENT_FRAGMENT_NODE :
          typestring = "DOCUMENT_FRAGMENT_NODE";
          break;
        case DTM.DOCUMENT_NODE :
          typestring = "DOCUMENT_NODE";
          break;
        case DTM.DOCUMENT_TYPE_NODE :
          typestring = "DOCUMENT_NODE";
          break;
        case DTM.ELEMENT_NODE :
          typestring = "ELEMENT_NODE";
          break;
        case DTM.ENTITY_NODE :
          typestring = "ENTITY_NODE";
          break;
        case DTM.ENTITY_REFERENCE_NODE :
          typestring = "ENTITY_REFERENCE_NODE";
          break;
        case DTM.NAMESPACE_NODE :
          typestring = "NAMESPACE_NODE";
          break;
        case DTM.NOTATION_NODE :
          typestring = "NOTATION_NODE";
          break;
        case DTM.NULL :
          typestring = "NULL";
          break;
        case DTM.PROCESSING_INSTRUCTION_NODE :
          typestring = "PROCESSING_INSTRUCTION_NODE";
          break;
        case DTM.TEXT_NODE :
          typestring = "TEXT_NODE";
          break;
        default :
          typestring = "Unknown!";
          break;
        }

        ps.println("Type: " + typestring);

        int firstChild = _firstch(index);

        if (DTM.NULL == firstChild)
          ps.println("First child: DTM.NULL");
        else if (NOTPROCESSED == firstChild)
          ps.println("First child: NOTPROCESSED");
        else
          ps.println("First child: " + firstChild);

        if (m_prevsib != null)
        {
          int prevSibling = _prevsib(index);

          if (DTM.NULL == prevSibling)
            ps.println("Prev sibling: DTM.NULL");
          else if (NOTPROCESSED == prevSibling)
            ps.println("Prev sibling: NOTPROCESSED");
          else
            ps.println("Prev sibling: " + prevSibling);
        }

        int nextSibling = _nextsib(index);

        if (DTM.NULL == nextSibling)
          ps.println("Next sibling: DTM.NULL");
        else if (NOTPROCESSED == nextSibling)
          ps.println("Next sibling: NOTPROCESSED");
        else
          ps.println("Next sibling: " + nextSibling);

        int parent = _parent(index);

        if (DTM.NULL == parent)
          ps.println("Parent: DTM.NULL");
        else if (NOTPROCESSED == parent)
          ps.println("Parent: NOTPROCESSED");
        else
          ps.println("Parent: " + parent);

        int level = _level(index);

        ps.println("Level: " + level);
        ps.println("Node Value: " + getNodeValue(i));
        ps.println("String Value: " + getStringValue(i));
      }
    }
    catch(IOException ioe)
    {
      ioe.printStackTrace(System.err);
        throw new RuntimeException(ioe.getMessage());
    }
  }
  
  
Diagnostics function to dump a single node.
%REVIEW% KNOWN GLITCH: If you pass it a node index rather than a 
node handle, it works just fine... but the displayed identity 
number before the colon is different, which complicates comparing
it with nodes printed the other way. We could always OR the DTM ID
into the value, to suppress that distinction...
%REVIEW% This might want to be moved up to DTMDefaultBase, or possibly
DTM itself, since it's a useful diagnostic and uses only DTM's public
APIs.
/**
   * Diagnostics function to dump a single node.
   * 
   * %REVIEW% KNOWN GLITCH: If you pass it a node index rather than a 
   * node handle, it works just fine... but the displayed identity 
   * number before the colon is different, which complicates comparing
   * it with nodes printed the other way. We could always OR the DTM ID
   * into the value, to suppress that distinction...
   * 
   * %REVIEW% This might want to be moved up to DTMDefaultBase, or possibly
   * DTM itself, since it's a useful diagnostic and uses only DTM's public
   * APIs.
   */
  public String dumpNode(int nodeHandle)
  {	  
	  if(nodeHandle==DTM.NULL)
		  return "[null]";
		  
        String typestring;
        switch (getNodeType(nodeHandle))
        {
        case DTM.ATTRIBUTE_NODE :
          typestring = "ATTR";
          break;
        case DTM.CDATA_SECTION_NODE :
          typestring = "CDATA";
          break;
        case DTM.COMMENT_NODE :
          typestring = "COMMENT";
          break;
        case DTM.DOCUMENT_FRAGMENT_NODE :
          typestring = "DOC_FRAG";
          break;
        case DTM.DOCUMENT_NODE :
          typestring = "DOC";
          break;
        case DTM.DOCUMENT_TYPE_NODE :
          typestring = "DOC_TYPE";
          break;
        case DTM.ELEMENT_NODE :
          typestring = "ELEMENT";
          break;
        case DTM.ENTITY_NODE :
          typestring = "ENTITY";
          break;
        case DTM.ENTITY_REFERENCE_NODE :
          typestring = "ENT_REF";
          break;
        case DTM.NAMESPACE_NODE :
          typestring = "NAMESPACE";
          break;
        case DTM.NOTATION_NODE :
          typestring = "NOTATION";
          break;
        case DTM.NULL :
          typestring = "null";
          break;
        case DTM.PROCESSING_INSTRUCTION_NODE :
          typestring = "PI";
          break;
        case DTM.TEXT_NODE :
          typestring = "TEXT";
          break;
        default :
          typestring = "Unknown!";
          break;
        }

      StringBuffer sb=new StringBuffer();
	  sb.append("["+nodeHandle+": "+typestring+
				"(0x"+Integer.toHexString(getExpandedTypeID(nodeHandle))+") "+
				getNodeNameX(nodeHandle)+" {"+getNamespaceURI(nodeHandle)+"}"+
				"=\""+ getNodeValue(nodeHandle)+"\"]");
	  return sb.toString();
  }

  // ========= DTM Implementation Control Functions. ==============

  
Set an implementation dependent feature.

%REVIEW% Do we really expect to set features on DTMs?
Params:
featureId – A feature URL.
state – true if this feature should be on, false otherwise./**
   * Set an implementation dependent feature.
   * <p>
   * %REVIEW% Do we really expect to set features on DTMs?
   *
   * @param featureId A feature URL.
   * @param state true if this feature should be on, false otherwise.
   */
  public void setFeature(String featureId, boolean state){}

  // ========= Document Navigation Functions =========

  
Given a node handle, test if it has child nodes.
 %REVIEW% This is obviously useful at the DOM layer, where it
would permit testing this without having to create a proxy
node. It's less useful in the DTM API, where
(dtm.getFirstChild(nodeHandle)!=DTM.NULL) is just as fast and
almost as self-evident. But it's a convenience, and eases porting
of DOM code to DTM.  
Params:
nodeHandle – int Handle of the node.
Returns:
int true if the given node has child nodes./**
   * Given a node handle, test if it has child nodes.
   * <p> %REVIEW% This is obviously useful at the DOM layer, where it
   * would permit testing this without having to create a proxy
   * node. It's less useful in the DTM API, where
   * (dtm.getFirstChild(nodeHandle)!=DTM.NULL) is just as fast and
   * almost as self-evident. But it's a convenience, and eases porting
   * of DOM code to DTM.  </p>
   *
   * @param nodeHandle int Handle of the node.
   * @return int true if the given node has child nodes.
   */
  public boolean hasChildNodes(int nodeHandle)
  {

    int identity = makeNodeIdentity(nodeHandle);
    int firstChild = _firstch(identity);

    return firstChild != DTM.NULL;
  }
	
  
Given a node identity, return a node handle. If extended addressing
has been used (multiple DTM IDs), we need to map the high bits of the
identity into the proper DTM ID.
This has been made FINAL to facilitate inlining, since we do not expect
any subclass of DTMDefaultBase to ever change the algorithm. (I don't
really like doing so, and would love to have an excuse not to...)
%REVIEW% Is it worth trying to specialcase small documents?
%REVIEW% Should this be exposed at the package/public layers?
Params:
nodeIdentity – Internal offset to this node's records.
Returns:
NodeHandle (external representation of node)/** Given a node identity, return a node handle. If extended addressing
   * has been used (multiple DTM IDs), we need to map the high bits of the
   * identity into the proper DTM ID.
   * 
   * This has been made FINAL to facilitate inlining, since we do not expect
   * any subclass of DTMDefaultBase to ever change the algorithm. (I don't
   * really like doing so, and would love to have an excuse not to...)
   * 
   * %REVIEW% Is it worth trying to specialcase small documents?
   * %REVIEW% Should this be exposed at the package/public layers?
   * 
   * @param nodeIdentity Internal offset to this node's records.
   * @return NodeHandle (external representation of node)
   * */
  final public int makeNodeHandle(int nodeIdentity)
  {
    if(NULL==nodeIdentity) return NULL;
		
    if(JJK_DEBUG && nodeIdentity>DTMManager.IDENT_NODE_DEFAULT)
      System.err.println("GONK! (only useful in limited situations)");

    return m_dtmIdent.elementAt(nodeIdentity >>> DTMManager.IDENT_DTM_NODE_BITS)
      + (nodeIdentity & DTMManager.IDENT_NODE_DEFAULT) ;											
  }
	
  
Given a node handle, return a node identity. If extended addressing
has been used (multiple DTM IDs), we need to map the high bits of the
identity into the proper DTM ID and thence find the proper offset
to add to the low bits of the identity
This has been made FINAL to facilitate inlining, since we do not expect
any subclass of DTMDefaultBase to ever change the algorithm. (I don't
really like doing so, and would love to have an excuse not to...)
%OPT% Performance is critical for this operation.
%REVIEW% Should this be exposed at the package/public layers?
Params:
nodeHandle – (external representation of node)
Returns:
nodeIdentity Internal offset to this node's records./** Given a node handle, return a node identity. If extended addressing
   * has been used (multiple DTM IDs), we need to map the high bits of the
   * identity into the proper DTM ID and thence find the proper offset
   * to add to the low bits of the identity
   * 
   * This has been made FINAL to facilitate inlining, since we do not expect
   * any subclass of DTMDefaultBase to ever change the algorithm. (I don't
   * really like doing so, and would love to have an excuse not to...)
   * 
   * %OPT% Performance is critical for this operation.
   *
   * %REVIEW% Should this be exposed at the package/public layers?
   * 
   * @param nodeHandle (external representation of node)
   * @return nodeIdentity Internal offset to this node's records.
   * */
  final public int makeNodeIdentity(int nodeHandle)
  {
    if(NULL==nodeHandle) return NULL;

    if(m_mgrDefault!=null)
    {
      // Optimization: use the DTMManagerDefault's fast DTMID-to-offsets
      // table.  I'm not wild about this solution but this operation
      // needs need extreme speed.

      int whichDTMindex=nodeHandle>>>DTMManager.IDENT_DTM_NODE_BITS;

      // %REVIEW% Wish I didn't have to perform the pre-test, but
      // someone is apparently asking DTMs whether they contain nodes
      // which really don't belong to them. That's probably a bug
      // which should be fixed, but until it is:
      if(m_mgrDefault.m_dtms[whichDTMindex]!=this)
	return NULL;
      else
	return
	  m_mgrDefault.m_dtm_offsets[whichDTMindex]
	  | (nodeHandle & DTMManager.IDENT_NODE_DEFAULT);
    }
	  
    int whichDTMid=m_dtmIdent.indexOf(nodeHandle & DTMManager.IDENT_DTM_DEFAULT);
    return (whichDTMid==NULL) 
      ? NULL
      : (whichDTMid << DTMManager.IDENT_DTM_NODE_BITS)
      + (nodeHandle & DTMManager.IDENT_NODE_DEFAULT);
  }


  
Given a node handle, get the handle of the node's first child.
If not yet resolved, waits for more nodes to be added to the document and
tries again.
Params:
nodeHandle – int Handle of the node.
Returns:
int DTM node-number of first child, or DTM.NULL to indicate none exists./**
   * Given a node handle, get the handle of the node's first child.
   * If not yet resolved, waits for more nodes to be added to the document and
   * tries again.
   *
   * @param nodeHandle int Handle of the node.
   * @return int DTM node-number of first child, or DTM.NULL to indicate none exists.
   */
  public int getFirstChild(int nodeHandle)
  {

    int identity = makeNodeIdentity(nodeHandle);
    int firstChild = _firstch(identity);

    return makeNodeHandle(firstChild);
  }
  
  
Given a node handle, get the handle of the node's first child.
If not yet resolved, waits for more nodes to be added to the document and
tries again.
Params:
nodeHandle – int Handle of the node.
Returns:
int DTM node-number of first child, or DTM.NULL to indicate none exists./**
   * Given a node handle, get the handle of the node's first child.
   * If not yet resolved, waits for more nodes to be added to the document and
   * tries again.
   *
   * @param nodeHandle int Handle of the node.
   * @return int DTM node-number of first child, or DTM.NULL to indicate none exists.
   */
  public int getTypedFirstChild(int nodeHandle, int nodeType)
  {

    int firstChild, eType;
    if (nodeType < DTM.NTYPES) {
      for (firstChild = _firstch(makeNodeIdentity(nodeHandle));
           firstChild != DTM.NULL;
           firstChild = _nextsib(firstChild)) {
        eType = _exptype(firstChild);
        if (eType == nodeType
               || (eType >= DTM.NTYPES
                      && m_expandedNameTable.getType(eType) == nodeType)) {
          return makeNodeHandle(firstChild);
        }
      }
    } else {
      for (firstChild = _firstch(makeNodeIdentity(nodeHandle));
           firstChild != DTM.NULL;
           firstChild = _nextsib(firstChild)) {
        if (_exptype(firstChild) == nodeType) {
          return makeNodeHandle(firstChild);
        }
      }
    }
    return DTM.NULL;
  }

  
Given a node handle, advance to its last child.
If not yet resolved, waits for more nodes to be added to the document and
tries again.
Params:
nodeHandle – int Handle of the node.
Returns:
int Node-number of last child,
or DTM.NULL to indicate none exists./**
   * Given a node handle, advance to its last child.
   * If not yet resolved, waits for more nodes to be added to the document and
   * tries again.
   *
   * @param nodeHandle int Handle of the node.
   * @return int Node-number of last child,
   * or DTM.NULL to indicate none exists.
   */
  public int getLastChild(int nodeHandle)
  {

    int identity = makeNodeIdentity(nodeHandle);
    int child = _firstch(identity);
    int lastChild = DTM.NULL;

    while (child != DTM.NULL)
    {
      lastChild = child;
      child = _nextsib(child);
    }

    return makeNodeHandle(lastChild);
  }

  
Retrieves an attribute node by by qualified name and namespace URI.
Params:
nodeHandle – int Handle of the node upon which to look up this attribute..
namespaceURI – The namespace URI of the attribute to
  retrieve, or null.
name – The local name of the attribute to
  retrieve.
Returns:
The attribute node handle with the specified name (
  nodeName) or DTM.NULL if there is no such
  attribute./**
   * Retrieves an attribute node by by qualified name and namespace URI.
   *
   * @param nodeHandle int Handle of the node upon which to look up this attribute..
   * @param namespaceURI The namespace URI of the attribute to
   *   retrieve, or null.
   * @param name The local name of the attribute to
   *   retrieve.
   * @return The attribute node handle with the specified name (
   *   <code>nodeName</code>) or <code>DTM.NULL</code> if there is no such
   *   attribute.
   */
  public abstract int getAttributeNode(int nodeHandle, String namespaceURI,
                                       String name);

  
Given a node handle, get the index of the node's first attribute.
Params:
nodeHandle – int Handle of the node.
Returns:
Handle of first attribute, or DTM.NULL to indicate none exists./**
   * Given a node handle, get the index of the node's first attribute.
   *
   * @param nodeHandle int Handle of the node.
   * @return Handle of first attribute, or DTM.NULL to indicate none exists.
   */
  public int getFirstAttribute(int nodeHandle)
  {
    int nodeID = makeNodeIdentity(nodeHandle);

    return makeNodeHandle(getFirstAttributeIdentity(nodeID));
  }

  
Given a node identity, get the index of the node's first attribute.
Params:
identity – int identity of the node.
Returns:
Identity of first attribute, or DTM.NULL to indicate none exists./**
   * Given a node identity, get the index of the node's first attribute.
   *
   * @param identity int identity of the node.
   * @return Identity of first attribute, or DTM.NULL to indicate none exists.
   */
  protected int getFirstAttributeIdentity(int identity) {
    int type = _type(identity);

    if (DTM.ELEMENT_NODE == type)
    {
      // Assume that attributes and namespaces immediately follow the element.
      while (DTM.NULL != (identity = getNextNodeIdentity(identity)))
      {

        // Assume this can not be null.
        type = _type(identity);

        if (type == DTM.ATTRIBUTE_NODE)
        {
          return identity;
        }
        else if (DTM.NAMESPACE_NODE != type)
        {
          break;
        }
      }
    }

    return DTM.NULL;
  }

  
Given a node handle and an expanded type ID, get the index of the node's
attribute of that type, if any.
Params:
nodeHandle – int Handle of the node.
attType – int expanded type ID of the required attribute.
Returns:
Handle of attribute of the required type, or DTM.NULL to indicate
none exists./**
   * Given a node handle and an expanded type ID, get the index of the node's
   * attribute of that type, if any.
   *
   * @param nodeHandle int Handle of the node.
   * @param attType int expanded type ID of the required attribute.
   * @return Handle of attribute of the required type, or DTM.NULL to indicate
   * none exists.
   */
  protected int getTypedAttribute(int nodeHandle, int attType) {
    int type = getNodeType(nodeHandle);
    if (DTM.ELEMENT_NODE == type) {
      int identity = makeNodeIdentity(nodeHandle);

      while (DTM.NULL != (identity = getNextNodeIdentity(identity)))
      {
        type = _type(identity);

        if (type == DTM.ATTRIBUTE_NODE)
        {
          if (_exptype(identity) == attType) return makeNodeHandle(identity);
        }
        else if (DTM.NAMESPACE_NODE != type)
        {
          break;
        }
      }
    }

    return DTM.NULL;
  }

  
Given a node handle, advance to its next sibling.
If not yet resolved, waits for more nodes to be added to the document and
tries again.
Params:
nodeHandle – int Handle of the node.
Returns:
int Node-number of next sibling,
or DTM.NULL to indicate none exists./**
   * Given a node handle, advance to its next sibling.
   * If not yet resolved, waits for more nodes to be added to the document and
   * tries again.
   * @param nodeHandle int Handle of the node.
   * @return int Node-number of next sibling,
   * or DTM.NULL to indicate none exists.
   */
  public int getNextSibling(int nodeHandle)
  {
  	if (nodeHandle == DTM.NULL)
  	return DTM.NULL;
    return makeNodeHandle(_nextsib(makeNodeIdentity(nodeHandle)));
  }
  
  
Given a node handle, advance to its next sibling.
If not yet resolved, waits for more nodes to be added to the document and
tries again.
Params:
nodeHandle – int Handle of the node.
Returns:
int Node-number of next sibling,
or DTM.NULL to indicate none exists./**
   * Given a node handle, advance to its next sibling.
   * If not yet resolved, waits for more nodes to be added to the document and
   * tries again.
   * @param nodeHandle int Handle of the node.
   * @return int Node-number of next sibling,
   * or DTM.NULL to indicate none exists.
   */
  public int getTypedNextSibling(int nodeHandle, int nodeType)
  {
  	if (nodeHandle == DTM.NULL)
  	return DTM.NULL;
  	int node = makeNodeIdentity(nodeHandle);
  	int eType;
  	while ((node = _nextsib(node)) != DTM.NULL && 
  	((eType = _exptype(node)) != nodeType && 
  	m_expandedNameTable.getType(eType)!= nodeType)); 
  	//_type(node) != nodeType));
        
    return (node == DTM.NULL ? DTM.NULL : makeNodeHandle(node));
  }

  
Given a node handle, find its preceeding sibling.
WARNING: DTM is asymmetric; this operation is resolved by search, and is
relatively expensive.
Params:
nodeHandle – the id of the node.
Returns:
int Node-number of the previous sib,
or DTM.NULL to indicate none exists./**
   * Given a node handle, find its preceeding sibling.
   * WARNING: DTM is asymmetric; this operation is resolved by search, and is
   * relatively expensive.
   *
   * @param nodeHandle the id of the node.
   * @return int Node-number of the previous sib,
   * or DTM.NULL to indicate none exists.
   */
  public int getPreviousSibling(int nodeHandle)
  {
    if (nodeHandle == DTM.NULL)
      return DTM.NULL;
    
    if (m_prevsib != null)
      return makeNodeHandle(_prevsib(makeNodeIdentity(nodeHandle)));
    else
    {
      // If the previous sibling array is not built, we get at
      // the previous sibling using the parent, firstch and 
      // nextsib arrays. 
      int nodeID = makeNodeIdentity(nodeHandle);
      int parent = _parent(nodeID);
      int node = _firstch(parent);
      int result = DTM.NULL;
      while (node != nodeID)
      {
        result = node;
        node = _nextsib(node);
      }
      return makeNodeHandle(result);
    }
  }

  
Given a node handle, advance to the next attribute.
If an attr, we advance to
the next attr on the same node.  If not an attribute, we return NULL.
Params:
nodeHandle – int Handle of the node.
Returns:
int DTM node-number of the resolved attr,
or DTM.NULL to indicate none exists./**
   * Given a node handle, advance to the next attribute.
   * If an attr, we advance to
   * the next attr on the same node.  If not an attribute, we return NULL.
   *
   * @param nodeHandle int Handle of the node.
   * @return int DTM node-number of the resolved attr,
   * or DTM.NULL to indicate none exists.
   */
  public int getNextAttribute(int nodeHandle) {
    int nodeID = makeNodeIdentity(nodeHandle);

    if (_type(nodeID) == DTM.ATTRIBUTE_NODE) {
      return makeNodeHandle(getNextAttributeIdentity(nodeID));
    }

    return DTM.NULL;
  }

  
Given a node identity for an attribute, advance to the next attribute.
Params:
identity – int identity of the attribute node.  This
must be an attribute node.
Returns:
int DTM node-identity of the resolved attr,
or DTM.NULL to indicate none exists./**
   * Given a node identity for an attribute, advance to the next attribute.
   *
   * @param identity int identity of the attribute node.  This
   * <strong>must</strong> be an attribute node.
   *
   * @return int DTM node-identity of the resolved attr,
   * or DTM.NULL to indicate none exists.
   *
   */
  protected int getNextAttributeIdentity(int identity) {
    // Assume that attributes and namespace nodes immediately follow the element
    while (DTM.NULL != (identity = getNextNodeIdentity(identity))) {
      int type = _type(identity);

      if (type == DTM.ATTRIBUTE_NODE) {
        return identity;
      } else if (type != DTM.NAMESPACE_NODE) {
        break;
      }
    }

    return DTM.NULL;
  }

  
Lazily created namespace lists. /** Lazily created namespace lists. */
  private Vector m_namespaceLists = null;  // on demand


  
Build table of namespace declaration
locations during DTM construction. Table is a Vector of
SuballocatedIntVectors containing the namespace node HANDLES declared at
that ID, plus an SuballocatedIntVector of the element node INDEXES at which
these declarations appeared.
NOTE: Since this occurs during model build, nodes will be encountered
in doucment order and thus the table will be ordered by element,
permitting binary-search as a possible retrieval optimization.
%REVIEW% Directly managed arrays rather than vectors?
%REVIEW% Handles or IDs? Given usage, I think handles.
/** Build table of namespace declaration
   * locations during DTM construction. Table is a Vector of
   * SuballocatedIntVectors containing the namespace node HANDLES declared at
   * that ID, plus an SuballocatedIntVector of the element node INDEXES at which
   * these declarations appeared.
   *
   * NOTE: Since this occurs during model build, nodes will be encountered
   * in doucment order and thus the table will be ordered by element,
   * permitting binary-search as a possible retrieval optimization.
   *
   * %REVIEW% Directly managed arrays rather than vectors?
   * %REVIEW% Handles or IDs? Given usage, I think handles.
   * */
  protected void declareNamespaceInContext(int elementNodeIndex,int namespaceNodeIndex)
  {
    SuballocatedIntVector nsList=null;
    if(m_namespaceDeclSets==null)
      {

        // First
        m_namespaceDeclSetElements=new SuballocatedIntVector(32);
        m_namespaceDeclSetElements.addElement(elementNodeIndex);
        m_namespaceDeclSets=new Vector();
        nsList=new SuballocatedIntVector(32);
        m_namespaceDeclSets.addElement(nsList);
      }
    else
      {
        // Most recent. May be -1 (none) if DTM was pruned.
        // %OPT% Is there a lastElement() method? Should there be?
        int last=m_namespaceDeclSetElements.size()-1;
	        
        if(last>=0 && elementNodeIndex==m_namespaceDeclSetElements.elementAt(last))
          {
            nsList=(SuballocatedIntVector)m_namespaceDeclSets.elementAt(last);
          }
      }
    if(nsList==null)
      {
        m_namespaceDeclSetElements.addElement(elementNodeIndex);

        SuballocatedIntVector inherited =
                                findNamespaceContext(_parent(elementNodeIndex));

        if (inherited!=null) {
            // %OPT% Count-down might be faster, but debuggability may
            // be better this way, and if we ever decide we want to
            // keep this ordered by expanded-type...
            int isize=inherited.size();

            // Base the size of a new namespace list on the
            // size of the inherited list - but within reason!
            nsList=new SuballocatedIntVector(Math.max(Math.min(isize+16,2048),
                                                      32));

            for(int i=0;i<isize;++i)
              {
                nsList.addElement(inherited.elementAt(i));
              }
        } else {
            nsList=new SuballocatedIntVector(32);
        }

        m_namespaceDeclSets.addElement(nsList);
      }

    // Handle overwriting inherited.
    // %OPT% Keep sorted? (By expanded-name rather than by doc order...)
    // Downside: Would require insertElementAt if not found,
    // which has recopying costs. But these are generally short lists...
    int newEType=_exptype(namespaceNodeIndex);

    for(int i=nsList.size()-1;i>=0;--i)
      {
        if(newEType==getExpandedTypeID(nsList.elementAt(i)))
          {
            nsList.setElementAt(makeNodeHandle(namespaceNodeIndex),i);
            return;
          }
      }
    nsList.addElement(makeNodeHandle(namespaceNodeIndex));
  }

  
Retrieve list of namespace declaration locations
active at this node. List is an SuballocatedIntVector whose
entries are the namespace node HANDLES declared at that ID.
%REVIEW% Directly managed arrays rather than vectors?
%REVIEW% Handles or IDs? Given usage, I think handles.
/** Retrieve list of namespace declaration locations
     * active at this node. List is an SuballocatedIntVector whose
     * entries are the namespace node HANDLES declared at that ID.
     *
     * %REVIEW% Directly managed arrays rather than vectors?
     * %REVIEW% Handles or IDs? Given usage, I think handles.
     * */
  protected SuballocatedIntVector findNamespaceContext(int elementNodeIndex)
  {
    if (null!=m_namespaceDeclSetElements)
      {
        // %OPT% Is binary-search really saving us a lot versus linear?
        // (... It may be, in large docs with many NS decls.)
        int wouldBeAt=findInSortedSuballocatedIntVector(m_namespaceDeclSetElements,
                                            elementNodeIndex);
        if(wouldBeAt>=0) // Found it
          return (SuballocatedIntVector) m_namespaceDeclSets.elementAt(wouldBeAt);
        if(wouldBeAt == -1) // -1-wouldbeat == 0
          return null; // Not after anything; definitely not found

        // Not found, but we know where it should have been.
        // Search back until we find an ancestor or run out.
        wouldBeAt=-1-wouldBeAt;

        // Decrement wouldBeAt to find last possible ancestor
        int candidate=m_namespaceDeclSetElements.elementAt(-- wouldBeAt);
        int ancestor=_parent(elementNodeIndex);

        // Special case: if the candidate is before the given node, and
        // is in the earliest possible position in the document, it
        // must have the namespace declarations we're interested in.
        if (wouldBeAt == 0 && candidate < ancestor) {
          int rootHandle = getDocumentRoot(makeNodeHandle(elementNodeIndex));
          int rootID = makeNodeIdentity(rootHandle);
          int uppermostNSCandidateID;

          if (getNodeType(rootHandle) == DTM.DOCUMENT_NODE) {
            int ch = _firstch(rootID);
            uppermostNSCandidateID = (ch != DTM.NULL) ? ch : rootID;
          } else {
            uppermostNSCandidateID = rootID;
          }

          if (candidate == uppermostNSCandidateID) {
            return (SuballocatedIntVector)m_namespaceDeclSets.elementAt(wouldBeAt);
          }
        }

        while(wouldBeAt>=0 && ancestor>0)
          {
            if (candidate==ancestor) {
                // Found ancestor in list
                return (SuballocatedIntVector)m_namespaceDeclSets.elementAt(wouldBeAt);
            } else if (candidate<ancestor) {
                // Too deep in tree
                do {
                  ancestor=_parent(ancestor);
                } while (candidate < ancestor);
            } else if(wouldBeAt > 0){
              // Too late in list
              candidate=m_namespaceDeclSetElements.elementAt(--wouldBeAt);
            }
            else
            	break;
          }
      }

    return null; // No namespaces known at this node
  }

  
Subroutine: Locate the specified node within
m_namespaceDeclSetElements, or the last element which
preceeds it in document order
%REVIEW% Inlne this into findNamespaceContext? Create SortedSuballocatedIntVector type?
Returns:
If positive or zero, the index of the found item.
If negative, index of the point at which it would have appeared,
encoded as -1-index and hence reconvertable by subtracting
it from -1. (Encoding because I don't want to recompare the strings
but don't want to burn bytes on a datatype to hold a flagged value.)/**
     * Subroutine: Locate the specified node within
     * m_namespaceDeclSetElements, or the last element which
     * preceeds it in document order
     *
     * %REVIEW% Inlne this into findNamespaceContext? Create SortedSuballocatedIntVector type?
     *
     * @return If positive or zero, the index of the found item.
     * If negative, index of the point at which it would have appeared,
     * encoded as -1-index and hence reconvertable by subtracting
     * it from -1. (Encoding because I don't want to recompare the strings
     * but don't want to burn bytes on a datatype to hold a flagged value.)
     */
  protected int findInSortedSuballocatedIntVector(SuballocatedIntVector vector, int lookfor)
  {
    // Binary search
    int i = 0;
    if(vector != null) {
      int first = 0;
      int last  = vector.size() - 1;

      while (first <= last) {
        i = (first + last) / 2;
        int test = lookfor-vector.elementAt(i);
        if(test == 0) {
          return i; // Name found
        }
        else if (test < 0) {
          last = i - 1; // looked too late
        }
        else {
          first = i + 1; // looked ot early
        }
      }

      if (first > i) {
        i = first; // Clean up at loop end
      }
    }

    return -1 - i; // not-found has to be encoded.
  }


  
Given a node handle, get the index of the node's first child.
If not yet resolved, waits for more nodes to be added to the document and
tries again
Params:
nodeHandle – handle to node, which should probably be an element
                  node, but need not be.
inScope –    true if all namespaces in scope should be returned,
                  false if only the namespace declarations should be
                  returned.
Returns:
handle of first namespace, or DTM.NULL to indicate none exists./**
   * Given a node handle, get the index of the node's first child.
   * If not yet resolved, waits for more nodes to be added to the document and
   * tries again
   *
   * @param nodeHandle handle to node, which should probably be an element
   *                   node, but need not be.
   *
   * @param inScope    true if all namespaces in scope should be returned,
   *                   false if only the namespace declarations should be
   *                   returned.
   * @return handle of first namespace, or DTM.NULL to indicate none exists.
   */
  public int getFirstNamespaceNode(int nodeHandle, boolean inScope)
  {
        if(inScope)
        {
            int identity = makeNodeIdentity(nodeHandle);
            if (_type(identity) == DTM.ELEMENT_NODE)
            {
              SuballocatedIntVector nsContext=findNamespaceContext(identity);
              if(nsContext==null || nsContext.size()<1)
                return NULL;

              return nsContext.elementAt(0);
            }
            else
              return NULL;
          }
        else
          {
            // Assume that attributes and namespaces immediately
            // follow the element.
            //
            // %OPT% Would things be faster if all NS nodes were built
            // before all Attr nodes? Some costs at build time for 2nd
            // pass...
            int identity = makeNodeIdentity(nodeHandle);
            if (_type(identity) == DTM.ELEMENT_NODE)
            {
              while (DTM.NULL != (identity = getNextNodeIdentity(identity)))
              {
                int type = _type(identity);
                if (type == DTM.NAMESPACE_NODE)
                    return makeNodeHandle(identity);
                else if (DTM.ATTRIBUTE_NODE != type)
                    break;
              }
              return NULL;
            }
            else
              return NULL;
          }
  }

  
Given a namespace handle, advance to the next namespace.
Params:
baseHandle – handle to original node from where the first namespace
was relative to (needed to return nodes in document order).
nodeHandle – A namespace handle for which we will find the next node.
inScope – true if all namespaces that are in scope should be processed,
otherwise just process the nodes in the given element handle.
Returns:
handle of next namespace, or DTM.NULL to indicate none exists./**
   * Given a namespace handle, advance to the next namespace.
   *
   * @param baseHandle handle to original node from where the first namespace
   * was relative to (needed to return nodes in document order).
   * @param nodeHandle A namespace handle for which we will find the next node.
   * @param inScope true if all namespaces that are in scope should be processed,
   * otherwise just process the nodes in the given element handle.
   * @return handle of next namespace, or DTM.NULL to indicate none exists.
   */
  public int getNextNamespaceNode(int baseHandle, int nodeHandle,
                                  boolean inScope)
  {
        if(inScope)
          {
            //Since we've been given the base, try direct lookup
            //(could look from nodeHandle but this is at least one
            //comparison/get-parent faster)
            //SuballocatedIntVector nsContext=findNamespaceContext(nodeHandle & m_mask);

                SuballocatedIntVector nsContext=findNamespaceContext(makeNodeIdentity(baseHandle));

            if(nsContext==null)
              return NULL;
            int i=1 + nsContext.indexOf(nodeHandle);
            if(i<=0 || i==nsContext.size())
              return NULL;

            return nsContext.elementAt(i);
          }
        else
          {
            // Assume that attributes and namespace nodes immediately follow the element.
            int identity = makeNodeIdentity(nodeHandle);
            while (DTM.NULL != (identity = getNextNodeIdentity(identity)))
              {
                int type = _type(identity);
                if (type == DTM.NAMESPACE_NODE)
                  {
                    return makeNodeHandle(identity);
                  }
                else if (type != DTM.ATTRIBUTE_NODE)
                  {
                    break;
                  }
              }
          }
     return DTM.NULL;
  }

  
Given a node handle, find its parent node.
Params:
nodeHandle – the id of the node.
Returns:
int Node-number of parent,
or DTM.NULL to indicate none exists./**
   * Given a node handle, find its parent node.
   *
   * @param nodeHandle the id of the node.
   * @return int Node-number of parent,
   * or DTM.NULL to indicate none exists.
   */
  public int getParent(int nodeHandle)
  {

    int identity = makeNodeIdentity(nodeHandle);

    if (identity > 0)
      return makeNodeHandle(_parent(identity));
    else
      return DTM.NULL;
  }

  
Find the Document node handle for the document currently under construction.
PLEASE NOTE that most people should use getOwnerDocument(nodeHandle) instead;
this version of the operation is primarily intended for use during negotiation
with the DTM Manager.
 @return int Node handle of document, which should always be valid.
/**
   * Find the Document node handle for the document currently under construction.
   * PLEASE NOTE that most people should use getOwnerDocument(nodeHandle) instead;
   * this version of the operation is primarily intended for use during negotiation
   * with the DTM Manager.
   * 
   *  @return int Node handle of document, which should always be valid.
   */
  public int getDocument()
  {
    return m_dtmIdent.elementAt(0); // makeNodeHandle(0)
  }

  
Given a node handle, find the owning document node.  This has the exact
same semantics as the DOM Document method of the same name, in that if
the nodeHandle is a document node, it will return NULL.
%REVIEW% Since this is DOM-specific, it may belong at the DOM
binding layer. Included here as a convenience function and to
aid porting of DOM code to DTM.
Params:
nodeHandle – the id of the node.
Returns:
int Node handle of owning document, or -1 if the node was a Docment/**
   * Given a node handle, find the owning document node.  This has the exact
   * same semantics as the DOM Document method of the same name, in that if
   * the nodeHandle is a document node, it will return NULL.
   *
   * <p>%REVIEW% Since this is DOM-specific, it may belong at the DOM
   * binding layer. Included here as a convenience function and to
   * aid porting of DOM code to DTM.</p>
   *
   * @param nodeHandle the id of the node.
   * @return int Node handle of owning document, or -1 if the node was a Docment
   */
  public int getOwnerDocument(int nodeHandle)
  {

    if (DTM.DOCUMENT_NODE == getNodeType(nodeHandle))
  	    return DTM.NULL;

    return getDocumentRoot(nodeHandle);
  }

  
Given a node handle, find the owning document node.  Unlike the DOM,
this considers the owningDocument of a Document to be itself.
Params:
nodeHandle – the id of the node.
Returns:
int Node handle of owning document, or the nodeHandle if it is
            a Document./**
   * Given a node handle, find the owning document node.  Unlike the DOM,
   * this considers the owningDocument of a Document to be itself.
   *
   * @param nodeHandle the id of the node.
   * @return int Node handle of owning document, or the nodeHandle if it is
   *             a Document.
   */
  public int getDocumentRoot(int nodeHandle)
  {
    return getManager().getDTM(nodeHandle).getDocument();
  }

  
Get the string-value of a node as a String object
(see http://www.w3.org/TR/xpath#data-model
for the definition of a node's string-value).
Params:
nodeHandle – The node ID.
Returns:
A string object that represents the string-value of the given node./**
   * Get the string-value of a node as a String object
   * (see http://www.w3.org/TR/xpath#data-model
   * for the definition of a node's string-value).
   *
   * @param nodeHandle The node ID.
   *
   * @return A string object that represents the string-value of the given node.
   */
  public abstract XMLString getStringValue(int nodeHandle);

  
Get number of character array chunks in
the string-value of a node.
(see http://www.w3.org/TR/xpath#data-model
for the definition of a node's string-value).
Note that a single text node may have multiple text chunks.
Params:
nodeHandle – The node ID.
Returns:
number of character array chunks in
        the string-value of a node./**
   * Get number of character array chunks in
   * the string-value of a node.
   * (see http://www.w3.org/TR/xpath#data-model
   * for the definition of a node's string-value).
   * Note that a single text node may have multiple text chunks.
   *
   * @param nodeHandle The node ID.
   *
   * @return number of character array chunks in
   *         the string-value of a node.
   */
  public int getStringValueChunkCount(int nodeHandle)
  {

    // %TBD%
    error(XMLMessages.createXMLMessage(XMLErrorResources.ER_METHOD_NOT_SUPPORTED, null));//("getStringValueChunkCount not yet supported!");

    return 0;
  }

  
Get a character array chunk in the string-value of a node.
(see http://www.w3.org/TR/xpath#data-model
for the definition of a node's string-value).
Note that a single text node may have multiple text chunks.
Params:
nodeHandle – The node ID.
chunkIndex – Which chunk to get.
startAndLen – An array of 2 where the start position and length of
                   the chunk will be returned.
Returns:
The character array reference where the chunk occurs./**
   * Get a character array chunk in the string-value of a node.
   * (see http://www.w3.org/TR/xpath#data-model
   * for the definition of a node's string-value).
   * Note that a single text node may have multiple text chunks.
   *
   * @param nodeHandle The node ID.
   * @param chunkIndex Which chunk to get.
   * @param startAndLen An array of 2 where the start position and length of
   *                    the chunk will be returned.
   *
   * @return The character array reference where the chunk occurs.
   */
  public char[] getStringValueChunk(int nodeHandle, int chunkIndex,
                                    int[] startAndLen)
  {

    // %TBD%
    error(XMLMessages.createXMLMessage(XMLErrorResources.ER_METHOD_NOT_SUPPORTED, null));//"getStringValueChunk not yet supported!");

    return null;
  }

  
Given a node handle, return an ID that represents the node's expanded name.
Params:
nodeHandle – The handle to the node in question.
Returns:
the expanded-name id of the node./**
   * Given a node handle, return an ID that represents the node's expanded name.
   *
   * @param nodeHandle The handle to the node in question.
   *
   * @return the expanded-name id of the node.
   */
  public int getExpandedTypeID(int nodeHandle)
  {
    // %REVIEW% This _should_ only be null if someone asked the wrong DTM about the node...
    // which one would hope would never happen...
    int id=makeNodeIdentity(nodeHandle);
    if(id==NULL)
      return NULL;
    return _exptype(id);
  }

  
Given an expanded name, return an ID.  If the expanded-name does not
exist in the internal tables, the entry will be created, and the ID will
be returned.  Any additional nodes that are created that have this
expanded name will use this ID.
Params:
type – The simple type, i.e. one of ELEMENT, ATTRIBUTE, etc.
namespace – The namespace URI, which may be null, may be an empty
                 string (which will be the same as null), or may be a
                 namespace URI.
localName – The local name string, which must be a valid
                 NCName.
Returns:
the expanded-name id of the node./**
   * Given an expanded name, return an ID.  If the expanded-name does not
   * exist in the internal tables, the entry will be created, and the ID will
   * be returned.  Any additional nodes that are created that have this
   * expanded name will use this ID.
   *
   * @param type The simple type, i.e. one of ELEMENT, ATTRIBUTE, etc.
   *
   * @param namespace The namespace URI, which may be null, may be an empty
   *                  string (which will be the same as null), or may be a
   *                  namespace URI.
   * @param localName The local name string, which must be a valid
   *                  <a href="http://www.w3.org/TR/REC-xml-names/">NCName</a>.
   *
   * @return the expanded-name id of the node.
   */
  public int getExpandedTypeID(String namespace, String localName, int type)
  {

    ExpandedNameTable ent = m_expandedNameTable;

    return ent.getExpandedTypeID(namespace, localName, type);
  }

  
Given an expanded-name ID, return the local name part.
Params:
expandedNameID – an ID that represents an expanded-name.
Returns:
String Local name of this node./**
   * Given an expanded-name ID, return the local name part.
   *
   * @param expandedNameID an ID that represents an expanded-name.
   * @return String Local name of this node.
   */
  public String getLocalNameFromExpandedNameID(int expandedNameID)
  {
    return m_expandedNameTable.getLocalName(expandedNameID);
  }

  
Given an expanded-name ID, return the namespace URI part.
Params:
expandedNameID – an ID that represents an expanded-name.
Returns:
String URI value of this node's namespace, or null if no
namespace was resolved./**
   * Given an expanded-name ID, return the namespace URI part.
   *
   * @param expandedNameID an ID that represents an expanded-name.
   * @return String URI value of this node's namespace, or null if no
   * namespace was resolved.
   */
  public String getNamespaceFromExpandedNameID(int expandedNameID)
  {
    return m_expandedNameTable.getNamespace(expandedNameID);
  }

  
Returns the namespace type of a specific node
Params:
nodeHandle – the id of the node.
Returns:
the ID of the namespace./**
   * Returns the namespace type of a specific node
   * @param nodeHandle the id of the node.
   * @return the ID of the namespace.
   */
  public int getNamespaceType(final int nodeHandle)
  {

    int identity = makeNodeIdentity(nodeHandle);
    int expandedNameID = _exptype(identity);

    return m_expandedNameTable.getNamespaceID(expandedNameID);
  }

  
Given a node handle, return its DOM-style node name. This will
include names such as #text or #document.
Params:
nodeHandle – the id of the node.
Returns:
String Name of this node, which may be an empty string.
%REVIEW% Document when empty string is possible...
%REVIEW-COMMENT% It should never be empty, should it?/**
   * Given a node handle, return its DOM-style node name. This will
   * include names such as #text or #document.
   *
   * @param nodeHandle the id of the node.
   * @return String Name of this node, which may be an empty string.
   * %REVIEW% Document when empty string is possible...
   * %REVIEW-COMMENT% It should never be empty, should it?
   */
  public abstract String getNodeName(int nodeHandle);

  
Given a node handle, return the XPath node name.  This should be
the name as described by the XPath data model, NOT the DOM-style
name.
Params:
nodeHandle – the id of the node.
Returns:
String Name of this node, which may be an empty string./**
   * Given a node handle, return the XPath node name.  This should be
   * the name as described by the XPath data model, NOT the DOM-style
   * name.
   *
   * @param nodeHandle the id of the node.
   * @return String Name of this node, which may be an empty string.
   */
  public String getNodeNameX(int nodeHandle)
  {

    /** @todo: implement this org.apache.xml.dtm.DTMDefaultBase abstract method */
    error(XMLMessages.createXMLMessage(XMLErrorResources.ER_METHOD_NOT_SUPPORTED, null));//"Not yet supported!");

    return null;
  }

  
Given a node handle, return its XPath-style localname.
(As defined in Namespaces, this is the portion of the name after any
colon character).
Params:
nodeHandle – the id of the node.
Returns:
String Local name of this node./**
   * Given a node handle, return its XPath-style localname.
   * (As defined in Namespaces, this is the portion of the name after any
   * colon character).
   *
   * @param nodeHandle the id of the node.
   * @return String Local name of this node.
   */
  public abstract String getLocalName(int nodeHandle);

  
Given a namespace handle, return the prefix that the namespace decl is
mapping.
Given a node handle, return the prefix used to map to the namespace.
 %REVIEW% Are you sure you want "" for no prefix?  
 %REVIEW-COMMENT% I think so... not totally sure. -sb  
Params:
nodeHandle – the id of the node.
Returns:
String prefix of this node's name, or "" if no explicit
namespace prefix was given./**
   * Given a namespace handle, return the prefix that the namespace decl is
   * mapping.
   * Given a node handle, return the prefix used to map to the namespace.
   *
   * <p> %REVIEW% Are you sure you want "" for no prefix?  </p>
   * <p> %REVIEW-COMMENT% I think so... not totally sure. -sb  </p>
   *
   * @param nodeHandle the id of the node.
   * @return String prefix of this node's name, or "" if no explicit
   * namespace prefix was given.
   */
  public abstract String getPrefix(int nodeHandle);

  
Given a node handle, return its DOM-style namespace URI
(As defined in Namespaces, this is the declared URI which this node's
prefix -- or default in lieu thereof -- was mapped to.)
%REVIEW% Null or ""? -sb
Params:
nodeHandle – the id of the node.
Returns:
String URI value of this node's namespace, or null if no
namespace was resolved./**
   * Given a node handle, return its DOM-style namespace URI
   * (As defined in Namespaces, this is the declared URI which this node's
   * prefix -- or default in lieu thereof -- was mapped to.)
   *
   * <p>%REVIEW% Null or ""? -sb</p>
   *
   * @param nodeHandle the id of the node.
   * @return String URI value of this node's namespace, or null if no
   * namespace was resolved.
   */
  public abstract String getNamespaceURI(int nodeHandle);

  
Given a node handle, return its node value. This is mostly
as defined by the DOM, but may ignore some conveniences.

Params:
nodeHandle – The node id.
Returns:
String Value of this node, or null if not
meaningful for this node type./**
   * Given a node handle, return its node value. This is mostly
   * as defined by the DOM, but may ignore some conveniences.
   * <p>
   *
   * @param nodeHandle The node id.
   * @return String Value of this node, or null if not
   * meaningful for this node type.
   */
  public abstract String getNodeValue(int nodeHandle);

  
Given a node handle, return its DOM-style node type.

%REVIEW% Generally, returning short is false economy. Return int?
%REVIEW% Make assumption that node has already arrived.  Is OK?
Params:
nodeHandle – The node id.
Returns:
int Node type, as per the DOM's Node._NODE constants./**
   * Given a node handle, return its DOM-style node type.
   * <p>
   * %REVIEW% Generally, returning short is false economy. Return int?
   * %REVIEW% Make assumption that node has already arrived.  Is OK?
   *
   * @param nodeHandle The node id.
   * @return int Node type, as per the DOM's Node._NODE constants.
   */
  public short getNodeType(int nodeHandle)
  {
  	if (nodeHandle == DTM.NULL)
  	return DTM.NULL;
    return m_expandedNameTable.getType(_exptype(makeNodeIdentity(nodeHandle)));
  }

  
Get the depth level of this node in the tree (equals 1 for
a parentless node).
Params:
nodeHandle – The node id.
Returns:
the number of ancestors, plus one
@xsl.usage
internal/**
   * Get the depth level of this node in the tree (equals 1 for
   * a parentless node).
   *
   * @param nodeHandle The node id.
   * @return the number of ancestors, plus one
   * @xsl.usage internal
   */
  public short getLevel(int nodeHandle)
  {
    // Apparently, the axis walker stuff requires levels to count from 1.
    int identity = makeNodeIdentity(nodeHandle);
    return (short) (_level(identity) + 1);
  }
  
  
Get the identity of this node in the tree 
Params:
nodeHandle – The node handle.
Returns:
the node identity
@xsl.usage
internal/**
   * Get the identity of this node in the tree 
   *
   * @param nodeHandle The node handle.
   * @return the node identity
   * @xsl.usage internal
   */
  public int getNodeIdent(int nodeHandle)
  {
    /*if (nodeHandle != DTM.NULL)
      return nodeHandle & m_mask;
    else 
      return DTM.NULL;*/
      
      return makeNodeIdentity(nodeHandle); 
  }
  
  
Get the handle of this node in the tree 
Params:
nodeId – The node identity.
Returns:
the node handle
@xsl.usage
internal/**
   * Get the handle of this node in the tree 
   *
   * @param nodeId The node identity.
   * @return the node handle
   * @xsl.usage internal
   */
  public int getNodeHandle(int nodeId)
  {
    /*if (nodeId != DTM.NULL)
      return nodeId | m_dtmIdent;
    else 
      return DTM.NULL;*/
      
      return makeNodeHandle(nodeId);
  }

  // ============== Document query functions ==============

  
Tests whether DTM DOM implementation implements a specific feature and
that feature is supported by this node.
Params:
feature – The name of the feature to test.
version – This is the version number of the feature to test.
  If the version is not
  specified, supporting any version of the feature will cause the
  method to return true.
Returns:
Returns true if the specified feature is
  supported on this node, false otherwise./**
   * Tests whether DTM DOM implementation implements a specific feature and
   * that feature is supported by this node.
   *
   * @param feature The name of the feature to test.
   * @param version This is the version number of the feature to test.
   *   If the version is not
   *   specified, supporting any version of the feature will cause the
   *   method to return <code>true</code>.
   * @return Returns <code>true</code> if the specified feature is
   *   supported on this node, <code>false</code> otherwise.
   */
  public boolean isSupported(String feature, String version)
  {

    // %TBD%
    return false;
  }

  
Return the base URI of the document entity. If it is not known
(because the document was parsed from a socket connection or from
standard input, for example), the value of this property is unknown.
Returns:
the document base URI String object or null if unknown./**
   * Return the base URI of the document entity. If it is not known
   * (because the document was parsed from a socket connection or from
   * standard input, for example), the value of this property is unknown.
   *
   * @return the document base URI String object or null if unknown.
   */
  public String getDocumentBaseURI()
  {
    return m_documentBaseURI;
  }

  
Set the base URI of the document entity.
Params:
baseURI – the document base URI String object or null if unknown./**
   * Set the base URI of the document entity.
   *
   * @param baseURI the document base URI String object or null if unknown.
   */
  public void setDocumentBaseURI(String baseURI)
  {
    m_documentBaseURI = baseURI;
  }

  
Return the system identifier of the document entity. If
it is not known, the value of this property is unknown.
Params:
nodeHandle – The node id, which can be any valid node handle.
Returns:
the system identifier String object or null if unknown./**
   * Return the system identifier of the document entity. If
   * it is not known, the value of this property is unknown.
   *
   * @param nodeHandle The node id, which can be any valid node handle.
   * @return the system identifier String object or null if unknown.
   */
  public String getDocumentSystemIdentifier(int nodeHandle)
  {

    // %REVIEW%  OK? -sb
    return m_documentBaseURI;
  }

  
Return the name of the character encoding scheme
       in which the document entity is expressed.
Params:
nodeHandle – The node id, which can be any valid node handle.
Returns:
the document encoding String object.
@xsl.usage
internal/**
   * Return the name of the character encoding scheme
   *        in which the document entity is expressed.
   *
   * @param nodeHandle The node id, which can be any valid node handle.
   * @return the document encoding String object.
   * @xsl.usage internal
   */
  public String getDocumentEncoding(int nodeHandle)
  {

    // %REVIEW%  OK??  -sb
    return "UTF-8";
  }

  
Return an indication of the standalone status of the document,
       either "yes" or "no". This property is derived from the optional
       standalone document declaration in the XML declaration at the
       beginning of the document entity, and has no value if there is no
       standalone document declaration.
Params:
nodeHandle – The node id, which can be any valid node handle.
Returns:
the document standalone String object, either "yes", "no", or null./**
   * Return an indication of the standalone status of the document,
   *        either "yes" or "no". This property is derived from the optional
   *        standalone document declaration in the XML declaration at the
   *        beginning of the document entity, and has no value if there is no
   *        standalone document declaration.
   *
   * @param nodeHandle The node id, which can be any valid node handle.
   * @return the document standalone String object, either "yes", "no", or null.
   */
  public String getDocumentStandalone(int nodeHandle)
  {
    return null;
  }

  
Return a string representing the XML version of the document. This
property is derived from the XML declaration optionally present at the
beginning of the document entity, and has no value if there is no XML
declaration.
Params:
documentHandle – The document handle
Returns:
the document version String object./**
   * Return a string representing the XML version of the document. This
   * property is derived from the XML declaration optionally present at the
   * beginning of the document entity, and has no value if there is no XML
   * declaration.
   *
   * @param documentHandle The document handle
   *
   * @return the document version String object.
   */
  public String getDocumentVersion(int documentHandle)
  {
    return null;
  }

  
Return an indication of
whether the processor has read the complete DTD. Its value is a
boolean. If it is false, then certain properties (indicated in their
descriptions below) may be unknown. If it is true, those properties
are never unknown.
Returns:
true if all declarations were processed;
        false otherwise./**
   * Return an indication of
   * whether the processor has read the complete DTD. Its value is a
   * boolean. If it is false, then certain properties (indicated in their
   * descriptions below) may be unknown. If it is true, those properties
   * are never unknown.
   *
   * @return <code>true</code> if all declarations were processed;
   *         <code>false</code> otherwise.
   */
  public boolean getDocumentAllDeclarationsProcessed()
  {

    // %REVIEW% OK?
    return true;
  }

  
  A document type declaration information item has the following properties:
    1. [system identifier] The system identifier of the external subset, if
       it exists. Otherwise this property has no value.
Returns:
the system identifier String object, or null if there is none./**
   *   A document type declaration information item has the following properties:
   *
   *     1. [system identifier] The system identifier of the external subset, if
   *        it exists. Otherwise this property has no value.
   *
   * @return the system identifier String object, or null if there is none.
   */
  public abstract String getDocumentTypeDeclarationSystemIdentifier();

  
Return the public identifier of the external subset,
normalized as described in 4.2.2 External Entities [XML]. If there is
no external subset or if it has no public identifier, this property
has no value.
Returns:
the public identifier String object, or null if there is none./**
   * Return the public identifier of the external subset,
   * normalized as described in 4.2.2 External Entities [XML]. If there is
   * no external subset or if it has no public identifier, this property
   * has no value.
   *
   * @return the public identifier String object, or null if there is none.
   */
  public abstract String getDocumentTypeDeclarationPublicIdentifier();

  
Returns the Element whose ID is given by
elementId. If no such element exists, returns
DTM.NULL. Behavior is not defined if more than one element
has this ID. Attributes (including those
with the name "ID") are not of type ID unless so defined by DTD/Schema
information available to the DTM implementation.
Implementations that do not know whether attributes are of type ID or
not are expected to return DTM.NULL.
%REVIEW% Presumably IDs are still scoped to a single document,
and this operation searches only within a single document, right?
Wouldn't want collisions between DTMs in the same process.
Params:
elementId – The unique id value for an element.
Returns:
The handle of the matching element./**
   * Returns the <code>Element</code> whose <code>ID</code> is given by
   * <code>elementId</code>. If no such element exists, returns
   * <code>DTM.NULL</code>. Behavior is not defined if more than one element
   * has this <code>ID</code>. Attributes (including those
   * with the name "ID") are not of type ID unless so defined by DTD/Schema
   * information available to the DTM implementation.
   * Implementations that do not know whether attributes are of type ID or
   * not are expected to return <code>DTM.NULL</code>.
   *
   * <p>%REVIEW% Presumably IDs are still scoped to a single document,
   * and this operation searches only within a single document, right?
   * Wouldn't want collisions between DTMs in the same process.</p>
   *
   * @param elementId The unique <code>id</code> value for an element.
   * @return The handle of the matching element.
   */
  public abstract int getElementById(String elementId);

  
The getUnparsedEntityURI function returns the URI of the unparsed
entity with the specified name in the same document as the context
node (see [3.3 Unparsed Entities]). It returns the empty string if
there is no such entity.

XML processors may choose to use the System Identifier (if one
is provided) to resolve the entity, rather than the URI in the
Public Identifier. The details are dependent on the processor, and
we would have to support some form of plug-in resolver to handle
this properly. Currently, we simply return the System Identifier if
present, and hope that it a usable URI or that our caller can
map it to one.
TODO: Resolve Public Identifiers... or consider changing function name.

If we find a relative URI
reference, XML expects it to be resolved in terms of the base URI
of the document. The DOM doesn't do that for us, and it isn't
entirely clear whether that should be done here; currently that's
pushed up to a higher level of our application. (Note that DOM Level
1 didn't store the document's base URI.)
TODO: Consider resolving Relative URIs.

(The DOM's statement that "An XML processor may choose to
completely expand entities before the structure model is passed
to the DOM" refers only to parsed entities, not unparsed, and hence
doesn't affect this function.)
Params:
name – A string containing the Entity Name of the unparsed
entity.
Returns:
String containing the URI of the Unparsed Entity, or an
empty string if no such entity exists./**
   * The getUnparsedEntityURI function returns the URI of the unparsed
   * entity with the specified name in the same document as the context
   * node (see [3.3 Unparsed Entities]). It returns the empty string if
   * there is no such entity.
   * <p>
   * XML processors may choose to use the System Identifier (if one
   * is provided) to resolve the entity, rather than the URI in the
   * Public Identifier. The details are dependent on the processor, and
   * we would have to support some form of plug-in resolver to handle
   * this properly. Currently, we simply return the System Identifier if
   * present, and hope that it a usable URI or that our caller can
   * map it to one.
   * TODO: Resolve Public Identifiers... or consider changing function name.
   * <p>
   * If we find a relative URI
   * reference, XML expects it to be resolved in terms of the base URI
   * of the document. The DOM doesn't do that for us, and it isn't
   * entirely clear whether that should be done here; currently that's
   * pushed up to a higher level of our application. (Note that DOM Level
   * 1 didn't store the document's base URI.)
   * TODO: Consider resolving Relative URIs.
   * <p>
   * (The DOM's statement that "An XML processor may choose to
   * completely expand entities before the structure model is passed
   * to the DOM" refers only to parsed entities, not unparsed, and hence
   * doesn't affect this function.)
   *
   * @param name A string containing the Entity Name of the unparsed
   * entity.
   *
   * @return String containing the URI of the Unparsed Entity, or an
   * empty string if no such entity exists.
   */
  public abstract String getUnparsedEntityURI(String name);

  // ============== Boolean methods ================

  
Return true if the xsl:strip-space or xsl:preserve-space was processed
during construction of the DTM document.
Returns:
true if this DTM supports prestripping./**
   * Return true if the xsl:strip-space or xsl:preserve-space was processed
   * during construction of the DTM document.
   *
   * @return true if this DTM supports prestripping.
   */
  public boolean supportsPreStripping()
  {
    return true;
  }

  
Figure out whether nodeHandle2 should be considered as being later
in the document than nodeHandle1, in Document Order as defined
by the XPath model. This may not agree with the ordering defined
by other XML applications.

There are some cases where ordering isn't defined, and neither are
the results of this function -- though we'll generally return false.
Params:
nodeHandle1 – Node handle to perform position comparison on.
nodeHandle2 – Second Node handle to perform position comparison on .
Returns:
true if node1 comes before node2, otherwise return false.
You can think of this as
(node1.documentOrderPosition <= node2.documentOrderPosition)./**
   * Figure out whether nodeHandle2 should be considered as being later
   * in the document than nodeHandle1, in Document Order as defined
   * by the XPath model. This may not agree with the ordering defined
   * by other XML applications.
   * <p>
   * There are some cases where ordering isn't defined, and neither are
   * the results of this function -- though we'll generally return false.
   *
   * @param nodeHandle1 Node handle to perform position comparison on.
   * @param nodeHandle2 Second Node handle to perform position comparison on .
   *
   * @return true if node1 comes before node2, otherwise return false.
   * You can think of this as
   * <code>(node1.documentOrderPosition &lt;= node2.documentOrderPosition)</code>.
   */
  public boolean isNodeAfter(int nodeHandle1, int nodeHandle2)
  {
		// These return NULL if the node doesn't belong to this document.
    int index1 = makeNodeIdentity(nodeHandle1);
    int index2 = makeNodeIdentity(nodeHandle2);

    return index1!=NULL && index2!=NULL && index1 <= index2;
  }

  
    2. [element content whitespace] A boolean indicating whether the
       character is white space appearing within element content (see [XML],
       2.10 "White Space Handling"). Note that validating XML processors are
       required by XML 1.0 to provide this information. If there is no
       declaration for the containing element, this property has no value for
       white space characters. If no declaration has been read, but the [all
       declarations processed] property of the document information item is
       false (so there may be an unread declaration), then the value of this
       property is unknown for white space characters. It is always false for
       characters that are not white space.
Params:
nodeHandle – the node ID.
Returns:
true if the character data is whitespace;
        false otherwise./**
   *     2. [element content whitespace] A boolean indicating whether the
   *        character is white space appearing within element content (see [XML],
   *        2.10 "White Space Handling"). Note that validating XML processors are
   *        required by XML 1.0 to provide this information. If there is no
   *        declaration for the containing element, this property has no value for
   *        white space characters. If no declaration has been read, but the [all
   *        declarations processed] property of the document information item is
   *        false (so there may be an unread declaration), then the value of this
   *        property is unknown for white space characters. It is always false for
   *        characters that are not white space.
   *
   * @param nodeHandle the node ID.
   * @return <code>true</code> if the character data is whitespace;
   *         <code>false</code> otherwise.
   */
  public boolean isCharacterElementContentWhitespace(int nodeHandle)
  {

    // %TBD%
    return false;
  }

  
   10. [all declarations processed] This property is not strictly speaking
       part of the infoset of the document. Rather it is an indication of
       whether the processor has read the complete DTD. Its value is a
       boolean. If it is false, then certain properties (indicated in their
       descriptions below) may be unknown. If it is true, those properties
       are never unknown.
Params:
documentHandle – A node handle that must identify a document.
Returns:
true if all declarations were processed;
        false otherwise./**
   *    10. [all declarations processed] This property is not strictly speaking
   *        part of the infoset of the document. Rather it is an indication of
   *        whether the processor has read the complete DTD. Its value is a
   *        boolean. If it is false, then certain properties (indicated in their
   *        descriptions below) may be unknown. If it is true, those properties
   *        are never unknown.
   *
   * @param documentHandle A node handle that must identify a document.
   * @return <code>true</code> if all declarations were processed;
   *         <code>false</code> otherwise.
   */
  public boolean isDocumentAllDeclarationsProcessed(int documentHandle)
  {
    return true;
  }

  
    5. [specified] A flag indicating whether this attribute was actually
       specified in the start-tag of its element, or was defaulted from the
       DTD.
Params:
attributeHandle – The attribute handle in question.
Returns:
true if the attribute was specified;
        false if it was defaulted./**
   *     5. [specified] A flag indicating whether this attribute was actually
   *        specified in the start-tag of its element, or was defaulted from the
   *        DTD.
   *
   * @param attributeHandle The attribute handle in question.
   *
   * @return <code>true</code> if the attribute was specified;
   *         <code>false</code> if it was defaulted.
   */
  public abstract boolean isAttributeSpecified(int attributeHandle);

  // ========== Direct SAX Dispatch, for optimization purposes ========

  
Directly call the
characters method on the passed ContentHandler for the
string-value of the given node (see http://www.w3.org/TR/xpath#data-model
for the definition of a node's string-value). Multiple calls to the
ContentHandler's characters methods may well occur for a single call to
this method.
Params:
nodeHandle – The node ID.
ch – A non-null reference to a ContentHandler.
normalize – true if the content should be normalized according to
the rules for the XPath
normalize-space
function.
Throws:
SAXException – /**
   * Directly call the
   * characters method on the passed ContentHandler for the
   * string-value of the given node (see http://www.w3.org/TR/xpath#data-model
   * for the definition of a node's string-value). Multiple calls to the
   * ContentHandler's characters methods may well occur for a single call to
   * this method.
   *
   * @param nodeHandle The node ID.
   * @param ch A non-null reference to a ContentHandler.
   * @param normalize true if the content should be normalized according to
   * the rules for the XPath
   * <a href="http://www.w3.org/TR/xpath#function-normalize-space">normalize-space</a>
   * function.
   *
   * @throws org.xml.sax.SAXException
   */
  public abstract void dispatchCharactersEvents(
    int nodeHandle, org.xml.sax.ContentHandler ch, boolean normalize)
      throws org.xml.sax.SAXException;

  
Directly create SAX parser events from a subtree.
Params:
nodeHandle – The node ID.
ch – A non-null reference to a ContentHandler.
Throws:
SAXException – /**
   * Directly create SAX parser events from a subtree.
   *
   * @param nodeHandle The node ID.
   * @param ch A non-null reference to a ContentHandler.
   *
   * @throws org.xml.sax.SAXException
   */
  public abstract void dispatchToEvents(
    int nodeHandle, org.xml.sax.ContentHandler ch)
      throws org.xml.sax.SAXException;

  
Return an DOM node for the given node.
Params:
nodeHandle – The node ID.
Returns:
A node representation of the DTM node./**
   * Return an DOM node for the given node.
   *
   * @param nodeHandle The node ID.
   *
   * @return A node representation of the DTM node.
   */
  public org.w3c.dom.Node getNode(int nodeHandle)
  {
    return new DTMNodeProxy(this, nodeHandle);
  }

  // ==== Construction methods (may not be supported by some implementations!) =====

  
Append a child to the end of the document. Please note that the node
is always cloned if it is owned by another document.
%REVIEW% "End of the document" needs to be defined more clearly.
Does it become the last child of the Document? Of the root element?
Params:
newChild – Must be a valid new node handle.
clone – true if the child should be cloned into the document.
cloneDepth – if the clone argument is true, specifies that the
                  clone should include all it's children./**
   * Append a child to the end of the document. Please note that the node
   * is always cloned if it is owned by another document.
   *
   * <p>%REVIEW% "End of the document" needs to be defined more clearly.
   * Does it become the last child of the Document? Of the root element?</p>
   *
   * @param newChild Must be a valid new node handle.
   * @param clone true if the child should be cloned into the document.
   * @param cloneDepth if the clone argument is true, specifies that the
   *                   clone should include all it's children.
   */
  public void appendChild(int newChild, boolean clone, boolean cloneDepth)
  {
    error(XMLMessages.createXMLMessage(XMLErrorResources.ER_METHOD_NOT_SUPPORTED, null));//"appendChild not yet supported!");
  }

  
Append a text node child that will be constructed from a string,
to the end of the document.
%REVIEW% "End of the document" needs to be defined more clearly.
Does it become the last child of the Document? Of the root element?
Params:
str – Non-null reverence to a string./**
   * Append a text node child that will be constructed from a string,
   * to the end of the document.
   *
   * <p>%REVIEW% "End of the document" needs to be defined more clearly.
   * Does it become the last child of the Document? Of the root element?</p>
   *
   * @param str Non-null reverence to a string.
   */
  public void appendTextChild(String str)
  {
    error(XMLMessages.createXMLMessage(XMLErrorResources.ER_METHOD_NOT_SUPPORTED, null));//"appendTextChild not yet supported!");
  }

  
Simple error for asserts and the like.
Params:
msg – Error message to report./**
   * Simple error for asserts and the like.
   *
   * @param msg Error message to report.
   */
  protected void error(String msg)
  {
    throw new DTMException(msg);
  }

  
Find out whether or not to strip whispace nodes.
Returns:
whether or not to strip whispace nodes./**
   * Find out whether or not to strip whispace nodes.
   *
   *
   * @return whether or not to strip whispace nodes.
   */
  protected boolean getShouldStripWhitespace()
  {
    return m_shouldStripWS;
  }

  
Set whether to strip whitespaces and push in current value of
m_shouldStripWS in m_shouldStripWhitespaceStack.
Params:
shouldStrip – Flag indicating whether to strip whitespace nodes/**
   * Set whether to strip whitespaces and push in current value of
   * m_shouldStripWS in m_shouldStripWhitespaceStack.
   *
   * @param shouldStrip Flag indicating whether to strip whitespace nodes
   */
  protected void pushShouldStripWhitespace(boolean shouldStrip)
  {

    m_shouldStripWS = shouldStrip;

    if (null != m_shouldStripWhitespaceStack)
      m_shouldStripWhitespaceStack.push(shouldStrip);
  }

  
Set whether to strip whitespaces at this point by popping out
m_shouldStripWhitespaceStack.
/**
   * Set whether to strip whitespaces at this point by popping out
   * m_shouldStripWhitespaceStack.
   *
   */
  protected void popShouldStripWhitespace()
  {
    if (null != m_shouldStripWhitespaceStack)
      m_shouldStripWS = m_shouldStripWhitespaceStack.popAndTop();
  }

  
Set whether to strip whitespaces and set the top of the stack to
the current value of m_shouldStripWS.
Params:
shouldStrip – Flag indicating whether to strip whitespace nodes/**
   * Set whether to strip whitespaces and set the top of the stack to
   * the current value of m_shouldStripWS.
   *
   *
   * @param shouldStrip Flag indicating whether to strip whitespace nodes
   */
  protected void setShouldStripWhitespace(boolean shouldStrip)
  {

    m_shouldStripWS = shouldStrip;

    if (null != m_shouldStripWhitespaceStack)
      m_shouldStripWhitespaceStack.setTop(shouldStrip);
  }

  
A dummy routine to satisify the abstract interface. If the DTM
implememtation that extends the default base requires notification
of registration, they can override this method.
/**
   * A dummy routine to satisify the abstract interface. If the DTM
   * implememtation that extends the default base requires notification
   * of registration, they can override this method.
   */
   public void documentRegistration()
   {
   }

  
A dummy routine to satisify the abstract interface. If the DTM
implememtation that extends the default base requires notification
when the document is being released, they can override this method
/**
   * A dummy routine to satisify the abstract interface. If the DTM
   * implememtation that extends the default base requires notification
   * when the document is being released, they can override this method
   */
   public void documentRelease()
   {
   }

   
Migrate a DTM built with an old DTMManager to a new DTMManager.
After the migration, the new DTMManager will treat the DTM as
one that is built by itself.
This is used to support DTM sharing between multiple transformations.
Params:
mgr – the DTMManager/**
    * Migrate a DTM built with an old DTMManager to a new DTMManager.
    * After the migration, the new DTMManager will treat the DTM as
    * one that is built by itself.
    * This is used to support DTM sharing between multiple transformations.
    * @param mgr the DTMManager
    */
   public void migrateTo(DTMManager mgr)
   {
     m_mgr = mgr;
     if(mgr instanceof DTMManagerDefault)
       m_mgrDefault=(DTMManagerDefault)mgr;     
   }      

	 
Query which DTMManager this DTM is currently being handled by.
%REVEW% Should this become part of the base DTM API?
Returns:
a DTMManager, or null if this is a "stand-alone" DTM./** Query which DTMManager this DTM is currently being handled by.
	  * 
	  * %REVEW% Should this become part of the base DTM API?
	  * 
	  * @return a DTMManager, or null if this is a "stand-alone" DTM.
	  */
	 public DTMManager getManager()
	 {
		 return m_mgr;
	 }

	 
Query which DTMIDs this DTM is currently using within the DTMManager.
%REVEW% Should this become part of the base DTM API?
Returns:
an IntVector, or null if this is a "stand-alone" DTM./** Query which DTMIDs this DTM is currently using within the DTMManager.
	  * 
	  * %REVEW% Should this become part of the base DTM API?
	  * 
	  * @return an IntVector, or null if this is a "stand-alone" DTM.
	  */
	 public SuballocatedIntVector getDTMIDs()
	 {
		 if(m_mgr==null) return null;
		 return m_dtmIdent;
	 }
}