content: /*
   * 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.
   */
  
  package mf.org.apache.xerces.impl.dtd.models;
  
  import java.util.HashMap;
  
  import mf.org.apache.xerces.impl.dtd.XMLContentSpec;
  import mf.org.apache.xerces.xni.QName;
  
  
  /**
   * DFAContentModel is the derivative of ContentModel that does
   * all of the non-trivial element content validation. This class does
   * the conversion from the regular expression to the DFA that
   * it then uses in its validation algorithm.
   * <p/>
   * <b>Note:</b> Upstream work insures that this class will never see
   * a content model with PCDATA in it. Any model with PCDATA is 'mixed'
   * and is handled via the MixedContentModel class since mixed models
   * are very constrained in form and easily handled via a special case.
   * This also makes implementation of this class much easier.
   *
   * @version $Id: DFAContentModel.java 572057 2007-09-02 18:03:20Z mrglavas $
   * @xerces.internal
   */
  public class DFAContentModel
          implements ContentModelValidator {
  
      //
      // Constants
      //
      // special strings
  
      /**
       * Set to true to debug content model validation.
       */
      private static final boolean DEBUG_VALIDATE_CONTENT = false;
      /**
       * Epsilon string.
       */
      private static String fEpsilonString = "<<CMNODE_EPSILON>>";
      /**
       * End-of-content string.
       */
      private static String fEOCString = "<<CMNODE_EOC>>";
  
      // debugging
  
      /** initializing static members **/
      static {
          fEpsilonString = fEpsilonString.intern();
          fEOCString = fEOCString.intern();
      }
  
      //
      // Data
      //
  
      /* this is the EquivClassComparator object */
      //private EquivClassComparator comparator = null;
  
      /**
       * Temporary qualified name.
       */
      private final QName fQName = new QName();
      /**
       * This is the map of unique input symbol elements to indices into
       * each state's per-input symbol transition table entry. This is part
       * of the built DFA information that must be kept around to do the
       * actual validation.
       */
      private QName fElemMap[] = null;
      /**
       * This is a map of whether the element map contains information
       * related to ANY models.
       */
      private int fElemMapType[] = null;
      /**
       * The element map size.
       */
      private int fElemMapSize = 0;
      /**
       * Boolean to distinguish Schema Mixed Content
       */
      private boolean fMixed;
      /**
       * The NFA position of the special EOC (end of content) node. This
       * is saved away since it's used during the DFA build.
       */
      private int fEOCPos = 0;
      /**
       * This is an array of booleans, one per state (there are
       * fTransTableSize states in the DFA) that indicates whether that
       * state is a final state.
       */
      private boolean fFinalStateFlags[] = null;
      /**
       * The list of follow positions for each NFA position (i.e. for each
       * non-epsilon leaf node.) This is only used during the building of
       * the DFA, and is let go afterwards.
       */
      private CMStateSet fFollowList[] = null;
      /**
       * This is the head node of our intermediate representation. It is
       * only non-null during the building of the DFA (just so that it
       * does not have to be passed all around.) Once the DFA is built,
       * this is no longer required so its nulled out.
       */
      private CMNode fHeadNode = null;
      /**
       * The count of leaf nodes. This is an important number that set some
       * limits on the sizes of data structures in the DFA process.
       */
      private int fLeafCount = 0;
      /**
       * An array of non-epsilon leaf nodes, which is used during the DFA
       * build operation, then dropped.
       */
      private CMLeaf fLeafList[] = null;
  
      //private ContentLeafNameTypeVector fLeafNameTypeVector = null;
  
      /**
       * The string pool of our parser session. This is set during construction
       * and kept around.
       */
      //private StringPool fStringPool = null;
      /**
       * Array mapping ANY types to the leaf list.
       */
      private int fLeafListType[] = null;
      /**
       * This is the transition table that is the main by product of all
       * of the effort here. It is an array of arrays of ints. The first
       * dimension is the number of states we end up with in the DFA. The
       * second dimensions is the number of unique elements in the content
       * model (fElemMapSize). Each entry in the second dimension indicates
       * the new state given that input for the first dimension's start
       * state.
       * <p/>
       * The fElemMap array handles mapping from element indexes to
       * positions in the second dimension of the transition table.
       */
      private int fTransTable[][] = null;
      /**
       * The number of valid entries in the transition table, and in the other
       * related tables such as fFinalStateFlags.
       */
      private int fTransTableSize = 0;
  
      // temp variables
      /**
       * Flag that indicates that even though we have a "complicated"
       * content model, it is valid to have no content. In other words,
       * all parts of the content model are optional. For example:
       * <pre>
       *      &lt;!ELEMENT AllOptional (Optional*,NotRequired?)&gt;
       * </pre>
       */
      private boolean fEmptyContentIsValid = false;
  
      //
      // Constructors
      //
  
  
      //
      // Constructors
      //
  
      /**
       * Constructs a DFA content model.
       *
       * @param syntaxTree The syntax tree of the content model.
       * @param leafCount  The number of leaves.
       * @param mixed
       */
      public DFAContentModel(CMNode syntaxTree, int leafCount, boolean mixed) {
          // Store away our index and pools in members
          //fStringPool = stringPool;
          fLeafCount = leafCount;
  
  
          // this is for Schema Mixed Content
          fMixed = mixed;
  
          //
          //  Ok, so lets grind through the building of the DFA. This method
          //  handles the high level logic of the algorithm, but it uses a
          //  number of helper classes to do its thing.
          //
          //  In order to avoid having hundreds of references to the error and
          //  string handlers around, this guy and all of his helper classes
          //  just throw a simple exception and we then pass it along.
          //
          buildDFA(syntaxTree);
      }
  
      //
      // ContentModelValidator methods
      //
  
      /**
       * Check that the specified content is valid according to this
       * content model. This method can also be called to do 'what if'
       * testing of content models just to see if they would be valid.
       * <p/>
       * A value of -1 in the children array indicates a PCDATA node. All other
       * indexes will be positive and represent child elements. The count can be
       * zero, since some elements have the EMPTY content model and that must be
       * confirmed.
       *
       * @param children The children of this element.  Each integer is an index within
       *                 the <code>StringPool</code> of the child element name.  An index
       *                 of -1 is used to indicate an occurrence of non-whitespace character
       *                 data.
       * @param offset   Offset into the array where the children starts.
       * @param length   The number of entries in the <code>children</code> array.
       * @return The value -1 if fully valid, else the 0 based index of the child
       * that first failed. If the value returned is equal to the number
       * of children, then the specified children are valid but additional
       * content is required to reach a valid ending state.
       */
      @Override
      public int validate(QName[] children, int offset, int length) {
  
          if (DEBUG_VALIDATE_CONTENT)
              System.out.println("DFAContentModel#validateContent");
  
          //
          // A DFA content model must *always* have at least 1 child
          // so a failure is given if no children present.
          // 
          // Defect 782: This is an incorrect statement because a DFA
          // content model is also used for constructions such as:
          //
          //     (Optional*,NotRequired?)
          //
          // where a perfectly valid content would be NO CHILDREN.
          // Therefore, if there are no children, we must check to
          // see if the CMNODE_EOC marker is a valid start state! -Ac
          //
          if (length == 0) {
              if (DEBUG_VALIDATE_CONTENT) {
                  System.out.println("!!! no children");
                  System.out.println("elemMap=" + fElemMap);
                  for (int i = 0; i < fElemMap.length; i++) {
                      String uri = fElemMap[i].uri;
                      String localpart = fElemMap[i].localpart;
  
                      System.out.println("fElemMap[" + i + "]=" + uri + "," +
                              localpart + " (" +
                              uri + ", " +
                              localpart +
                              ')');
  
                  }
                  System.out.println("EOCIndex=" + fEOCString);
              }
  
              return fEmptyContentIsValid ? -1 : 0;
  
          } // if child count == 0
  
          //
          //  Lets loop through the children in the array and move our way
          //  through the states. Note that we use the fElemMap array to map
          //  an element index to a state index.
          //
          int curState = 0;
          for (int childIndex = 0; childIndex < length; childIndex++) {
              // Get the current element index out
              final QName curElem = children[offset + childIndex];
              // ignore mixed text
              if (fMixed && curElem.localpart == null) {
                  continue;
              }
  
              // Look up this child in our element map
              int elemIndex = 0;
              for (; elemIndex < fElemMapSize; elemIndex++) {
                  int type = fElemMapType[elemIndex] & 0x0f;
                  if (type == XMLContentSpec.CONTENTSPECNODE_LEAF) {
                      //System.out.println("fElemMap["+elemIndex+"]: "+fElemMap[elemIndex]);
                      if (fElemMap[elemIndex].rawname == curElem.rawname) {
                          break;
                      }
                  } else if (type == XMLContentSpec.CONTENTSPECNODE_ANY) {
                      String uri = fElemMap[elemIndex].uri;
                      if (uri == null || uri == curElem.uri) {
                          break;
                      }
                  } else if (type == XMLContentSpec.CONTENTSPECNODE_ANY_LOCAL) {
                      if (curElem.uri == null) {
                          break;
                      }
                  } else if (type == XMLContentSpec.CONTENTSPECNODE_ANY_OTHER) {
                      if (fElemMap[elemIndex].uri != curElem.uri) {
                          break;
                      }
                  }
              }
  
              // If we didn't find it, then obviously not valid
              if (elemIndex == fElemMapSize) {
                  if (DEBUG_VALIDATE_CONTENT) {
                      System.out.println("!!! didn't find it");
  
                      System.out.println("curElem : " + curElem);
                      for (int i = 0; i < fElemMapSize; i++) {
                          System.out.println("fElemMap[" + i + "] = " + fElemMap[i]);
                          System.out.println("fElemMapType[" + i + "] = " + fElemMapType[i]);
                      }
                  }
  
                  return childIndex;
              }
  
              //
              //  Look up the next state for this input symbol when in the
              //  current state.
              //
              curState = fTransTable[curState][elemIndex];
  
              // If its not a legal transition, then invalid
              if (curState == -1) {
                  if (DEBUG_VALIDATE_CONTENT)
                      System.out.println("!!! not a legal transition");
                  return childIndex;
              }
          }
  
          //
          //  We transitioned all the way through the input list. However, that
          //  does not mean that we ended in a final state. So check whether
          //  our ending state is a final state.
          //
          if (DEBUG_VALIDATE_CONTENT)
              System.out.println("curState=" + curState + ", childCount=" + length);
          if (!fFinalStateFlags[curState])
              return length;
  
          // success!
          return -1;
      } // validate
  
  
      //
      // Private methods
      //
  
      /**
       * Builds the internal DFA transition table from the given syntax tree.
       *
       * @param syntaxTree The syntax tree.
       * @throws CMException Thrown if DFA cannot be built.
       */
      private void buildDFA(CMNode syntaxTree) {
          //
          //  The first step we need to take is to rewrite the content model
          //  using our CMNode objects, and in the process get rid of any
          //  repetition short cuts, converting them into '*' style repetitions
          //  or getting rid of repetitions altogether.
          //
          //  The conversions done are:
          //
          //  x+ -> (x|x*)
          //  x? -> (x|epsilon)
          //
          //  This is a relatively complex scenario. What is happening is that
          //  we create a top level binary node of which the special EOC value
          //  is set as the right side node. The the left side is set to the
          //  rewritten syntax tree. The source is the original content model
          //  info from the decl pool. The rewrite is done by buildSyntaxTree()
          //  which recurses the decl pool's content of the element and builds
          //  a new tree in the process.
          //
          //  Note that, during this operation, we set each non-epsilon leaf
          //  node's DFA state position and count the number of such leafs, which
          //  is left in the fLeafCount member.
          //
          //  The nodeTmp object is passed in just as a temp node to use during
          //  the recursion. Otherwise, we'd have to create a new node on every
          //  level of recursion, which would be piggy in Java (as is everything
          //  for that matter.)
          //
  
  	/* MODIFIED (Jan, 2001) 
       *
  	 * Use following rules.
  	 *   nullable(x+) := nullable(x), first(x+) := first(x),  last(x+) := last(x)
  	 *   nullable(x?) := true, first(x?) := first(x),  last(x?) := last(x)
  	 *
  	 * The same computation of follow as x* is applied to x+
  	 *
  	 * The modification drastically reduces computation time of
  	 * "(a, (b, a+, (c, (b, a+)+, a+, (d,  (c, (b, a+)+, a+)+, (b, a+)+, a+)+)+)+)+"
  	 */
  
          fQName.setValues(null, fEOCString, fEOCString, null);
          CMLeaf nodeEOC = new CMLeaf(fQName);
          fHeadNode = new CMBinOp
                  (
                          XMLContentSpec.CONTENTSPECNODE_SEQ
                          , syntaxTree
                          , nodeEOC
                  );
  
          //
          //  And handle specially the EOC node, which also must be numbered
          //  and counted as a non-epsilon leaf node. It could not be handled
          //  in the above tree build because it was created before all that
          //  started. We save the EOC position since its used during the DFA
          //  building loop.
          //
          fEOCPos = fLeafCount;
          nodeEOC.setPosition(fLeafCount++);
  
          //
          //  Ok, so now we have to iterate the new tree and do a little more
          //  work now that we know the leaf count. One thing we need to do is
          //  to calculate the first and last position sets of each node. This
          //  is cached away in each of the nodes.
          //
          //  Along the way we also set the leaf count in each node as the
          //  maximum state count. They must know this in order to create their
          //  first/last pos sets.
          //
          //  We also need to build an array of references to the non-epsilon
          //  leaf nodes. Since we iterate it in the same way as before, this
          //  will put them in the array according to their position values.
          //
          fLeafList = new CMLeaf[fLeafCount];
          fLeafListType = new int[fLeafCount];
          postTreeBuildInit(fHeadNode, 0);
  
          //
          //  And, moving onward... We now need to build the follow position
          //  sets for all the nodes. So we allocate an array of state sets,
          //  one for each leaf node (i.e. each DFA position.)
          //
          fFollowList = new CMStateSet[fLeafCount];
          for (int index = 0; index < fLeafCount; index++)
              fFollowList[index] = new CMStateSet(fLeafCount);
          calcFollowList(fHeadNode);
          //
          //  And finally the big push... Now we build the DFA using all the
          //  states and the tree we've built up. First we set up the various
          //  data structures we are going to use while we do this.
          //
          //  First of all we need an array of unique element names in our
          //  content model. For each transition table entry, we need a set of
          //  contiguous indices to represent the transitions for a particular
          //  input element. So we need to a zero based range of indexes that
          //  map to element types. This element map provides that mapping.
          //
          fElemMap = new QName[fLeafCount];
          fElemMapType = new int[fLeafCount];
          fElemMapSize = 0;
          for (int outIndex = 0; outIndex < fLeafCount; outIndex++) {
              fElemMap[outIndex] = new QName();
  
              /****
               if ( (fLeafListType[outIndex] & 0x0f) != 0 ) {
               if (fLeafNameTypeVector == null) {
               fLeafNameTypeVector = new ContentLeafNameTypeVector();
               }
               }
               /****/
  
              // Get the current leaf's element index
              final QName element = fLeafList[outIndex].getElement();
  
              // See if the current leaf node's element index is in the list
              int inIndex = 0;
              for (; inIndex < fElemMapSize; inIndex++) {
                  if (fElemMap[inIndex].rawname == element.rawname) {
                      break;
                  }
              }
  
              // If it was not in the list, then add it, if not the EOC node
              if (inIndex == fElemMapSize) {
                  fElemMap[fElemMapSize].setValues(element);
                  fElemMapType[fElemMapSize] = fLeafListType[outIndex];
                  fElemMapSize++;
              }
          }
          // set up the fLeafNameTypeVector object if there is one.
          /*****
           if (fLeafNameTypeVector != null) {
           fLeafNameTypeVector.setValues(fElemMap, fElemMapType, fElemMapSize);
           }
  
           /***
           * Optimization(Jan, 2001); We sort fLeafList according to
           * elemIndex which is *uniquely* associated to each leaf.
           * We are *assuming* that each element appears in at least one leaf.
           **/
  
          int[] fLeafSorter = new int[fLeafCount + fElemMapSize];
          int fSortCount = 0;
  
          for (int elemIndex = 0; elemIndex < fElemMapSize; elemIndex++) {
              for (int leafIndex = 0; leafIndex < fLeafCount; leafIndex++) {
                  final QName leaf = fLeafList[leafIndex].getElement();
                  final QName element = fElemMap[elemIndex];
                  if (leaf.rawname == element.rawname) {
                      fLeafSorter[fSortCount++] = leafIndex;
                  }
              }
              fLeafSorter[fSortCount++] = -1;
          }
  
  	/* Optimization(Jan, 2001) */
  
          //
          //  Next lets create some arrays, some that that hold transient
          //  information during the DFA build and some that are permament.
          //  These are kind of sticky since we cannot know how big they will
          //  get, but we don't want to use any Java collections because of
          //  performance.
          //
          //  Basically they will probably be about fLeafCount*2 on average,
          //  but can be as large as 2^(fLeafCount*2), worst case. So we start
          //  with fLeafCount*4 as a middle ground. This will be very unlikely
          //  to ever have to expand, though it if does, the overhead will be
          //  somewhat ugly.
          //
          int curArraySize = fLeafCount * 4;
          CMStateSet[] statesToDo = new CMStateSet[curArraySize];
          fFinalStateFlags = new boolean[curArraySize];
          fTransTable = new int[curArraySize][];
  
          //
          //  Ok we start with the initial set as the first pos set of the
          //  head node (which is the seq node that holds the content model
          //  and the EOC node.)
          //
          CMStateSet setT = fHeadNode.firstPos();
  
          //
          //  Init our two state flags. Basically the unmarked state counter
          //  is always chasing the current state counter. When it catches up,
          //  that means we made a pass through that did not add any new states
          //  to the lists, at which time we are done. We could have used a
          //  expanding array of flags which we used to mark off states as we
          //  complete them, but this is easier though less readable maybe.
          //
          int unmarkedState = 0;
          int curState = 0;
  
          //
          //  Init the first transition table entry, and put the initial state
          //  into the states to do list, then bump the current state.
          //
          fTransTable[curState] = makeDefStateList();
          statesToDo[curState] = setT;
          curState++;
  
  	    /* Optimization(Jan, 2001); This is faster for
           * a large content model such as, "(t001+|t002+|.... |t500+)".
  	     */
  
          HashMap stateTable = new HashMap();
  
  	    /* Optimization(Jan, 2001) */
  
          //
          //  Ok, almost done with the algorithm... We now enter the
          //  loop where we go until the states done counter catches up with
          //  the states to do counter.
          //
          while (unmarkedState < curState) {
              //
              //  Get the first unmarked state out of the list of states to do.
              //  And get the associated transition table entry.
              //
              setT = statesToDo[unmarkedState];
              int[] transEntry = fTransTable[unmarkedState];
  
              // Mark this one final if it contains the EOC state
              fFinalStateFlags[unmarkedState] = setT.getBit(fEOCPos);
  
              // Bump up the unmarked state count, marking this state done
              unmarkedState++;
  
              // Loop through each possible input symbol in the element map
              CMStateSet newSet = null;
          /* Optimization(Jan, 2001) */
              int sorterIndex = 0;
          /* Optimization(Jan, 2001) */
              for (int elemIndex = 0; elemIndex < fElemMapSize; elemIndex++) {
                  //
                  //  Build up a set of states which is the union of all of
                  //  the follow sets of DFA positions that are in the current
                  //  state. If we gave away the new set last time through then
                  //  create a new one. Otherwise, zero out the existing one.
                  //
                  if (newSet == null)
                      newSet = new CMStateSet(fLeafCount);
                  else
                      newSet.zeroBits();
  
  	    /* Optimization(Jan, 2001) */
                  int leafIndex = fLeafSorter[sorterIndex++];
  
                  while (leafIndex != -1) {
                      // If this leaf index (DFA position) is in the current set...
                      if (setT.getBit(leafIndex)) {
                          //
                          //  If this leaf is the current input symbol, then we
                          //  want to add its follow list to the set of states to
                          //  transition to from the current state.
                          //
                          newSet.union(fFollowList[leafIndex]);
                      }
  
                      leafIndex = fLeafSorter[sorterIndex++];
                  }
          /* Optimization(Jan, 2001) */
  
                  //
                  //  If this new set is not empty, then see if its in the list
                  //  of states to do. If not, then add it.
                  //
                  if (!newSet.isEmpty()) {
                      //
                      //  Search the 'states to do' list to see if this new
                      //  state set is already in there.
                      //
  
  	    /* Optimization(Jan, 2001) */
                      Integer stateObj = (Integer) stateTable.get(newSet);
                      int stateIndex = (stateObj == null ? curState : stateObj.intValue());
          /* Optimization(Jan, 2001) */
  
                      // If we did not find it, then add it
                      if (stateIndex == curState) {
                          //
                          //  Put this new state into the states to do and init
                          //  a new entry at the same index in the transition
                          //  table.
                          //
                          statesToDo[curState] = newSet;
                          fTransTable[curState] = makeDefStateList();
  
  	    /* Optimization(Jan, 2001) */
                          stateTable.put(newSet, new Integer(curState));
  	    /* Optimization(Jan, 2001) */
  
                          // We now have a new state to do so bump the count
                          curState++;
  
                          //
                          //  Null out the new set to indicate we adopted it.
                          //  This will cause the creation of a new set on the
                          //  next time around the loop.
                          //
                          newSet = null;
                      }
  
                      //
                      //  Now set this state in the transition table's entry
                      //  for this element (using its index), with the DFA
                      //  state we will move to from the current state when we
                      //  see this input element.
                      //
                      transEntry[elemIndex] = stateIndex;
  
                      // Expand the arrays if we're full
                      if (curState == curArraySize) {
                          //
                          //  Yikes, we overflowed the initial array size, so
                          //  we've got to expand all of these arrays. So adjust
                          //  up the size by 50% and allocate new arrays.
                          //
                          final int newSize = (int) (curArraySize * 1.5);
                          CMStateSet[] newToDo = new CMStateSet[newSize];
                          boolean[] newFinalFlags = new boolean[newSize];
                          int[][] newTransTable = new int[newSize][];
  
                          // Copy over all of the existing content
                          System.arraycopy(statesToDo, 0, newToDo, 0, curArraySize);
                          System.arraycopy(fFinalStateFlags, 0, newFinalFlags, 0, curArraySize);
                          System.arraycopy(fTransTable, 0, newTransTable, 0, curArraySize);
  
                          // Store the new array size
                          curArraySize = newSize;
                          statesToDo = newToDo;
                          fFinalStateFlags = newFinalFlags;
                          fTransTable = newTransTable;
                      }
                  }
              }
          }
  
          // Check to see if we can set the fEmptyContentIsValid flag.
          fEmptyContentIsValid = ((CMBinOp) fHeadNode).getLeft().isNullable();
  
          //
          //  And now we can say bye bye to the temp representation since we've
          //  built the DFA.
          //
          if (DEBUG_VALIDATE_CONTENT)
              dumpTree(fHeadNode, 0);
          fHeadNode = null;
          fLeafList = null;
          fFollowList = null;
  
      }
  
      /**
       * Calculates the follow list of the current node.
       *
       * @param nodeCur The curent node.
       * @throws CMException Thrown if follow list cannot be calculated.
       */
      private void calcFollowList(CMNode nodeCur) {
          // Recurse as required
          if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_CHOICE) {
              // Recurse only
              calcFollowList(((CMBinOp) nodeCur).getLeft());
              calcFollowList(((CMBinOp) nodeCur).getRight());
          } else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_SEQ) {
              // Recurse first
              calcFollowList(((CMBinOp) nodeCur).getLeft());
              calcFollowList(((CMBinOp) nodeCur).getRight());
  
              //
              //  Now handle our level. We use our left child's last pos
              //  set and our right child's first pos set, so go ahead and
              //  get them ahead of time.
              //
              final CMStateSet last = ((CMBinOp) nodeCur).getLeft().lastPos();
              final CMStateSet first = ((CMBinOp) nodeCur).getRight().firstPos();
  
              //
              //  Now, for every position which is in our left child's last set
              //  add all of the states in our right child's first set to the
              //  follow set for that position.
              //
              for (int index = 0; index < fLeafCount; index++) {
                  if (last.getBit(index))
                      fFollowList[index].union(first);
              }
          }
          /***
           else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ZERO_OR_MORE)
           {
           // Recurse first
           calcFollowList(((CMUniOp)nodeCur).getChild());
  
           //
           //  Now handle our level. We use our own first and last position
           //  sets, so get them up front.
           //
           final CMStateSet first = nodeCur.firstPos();
           final CMStateSet last  = nodeCur.lastPos();
  
           //
           //  For every position which is in our last position set, add all
           //  of our first position states to the follow set for that
           //  position.
           //
           for (int index = 0; index < fLeafCount; index++)
           {
           if (last.getBit(index))
           fFollowList[index].union(first);
           }
           }
           else if ((nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ONE_OR_MORE)
           ||  (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ZERO_OR_ONE))
           {
           throw new RuntimeException("ImplementationMessages.VAL_NIICM");
           }
           /***/
          else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ZERO_OR_MORE
                  || nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ONE_OR_MORE) {
              // Recurse first
              calcFollowList(((CMUniOp) nodeCur).getChild());
  
              //
              //  Now handle our level. We use our own first and last position
              //  sets, so get them up front.
              //
              final CMStateSet first = nodeCur.firstPos();
              final CMStateSet last = nodeCur.lastPos();
  
              //
              //  For every position which is in our last position set, add all
              //  of our first position states to the follow set for that
              //  position.
              //
              for (int index = 0; index < fLeafCount; index++) {
                  if (last.getBit(index))
                      fFollowList[index].union(first);
              }
          } else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ZERO_OR_ONE) {
              // Recurse only
              calcFollowList(((CMUniOp) nodeCur).getChild());
          }
          /***/
      }
  
      /**
       * Dumps the tree of the current node to standard output.
       *
       * @param nodeCur The current node.
       * @param level   The maximum levels to output.
       * @throws CMException Thrown on error.
       */
      private void dumpTree(CMNode nodeCur, int level) {
          for (int index = 0; index < level; index++)
              System.out.print("   ");
  
          int type = nodeCur.type();
          if ((type == XMLContentSpec.CONTENTSPECNODE_CHOICE)
                  || (type == XMLContentSpec.CONTENTSPECNODE_SEQ)) {
              if (type == XMLContentSpec.CONTENTSPECNODE_CHOICE)
                  System.out.print("Choice Node ");
              else
                  System.out.print("Seq Node ");
  
              if (nodeCur.isNullable())
                  System.out.print("Nullable ");
  
              System.out.print("firstPos=");
              System.out.print(nodeCur.firstPos().toString());
              System.out.print(" lastPos=");
              System.out.println(nodeCur.lastPos().toString());
  
              dumpTree(((CMBinOp) nodeCur).getLeft(), level + 1);
              dumpTree(((CMBinOp) nodeCur).getRight(), level + 1);
          } else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ZERO_OR_MORE) {
              System.out.print("Rep Node ");
  
              if (nodeCur.isNullable())
                  System.out.print("Nullable ");
  
              System.out.print("firstPos=");
              System.out.print(nodeCur.firstPos().toString());
              System.out.print(" lastPos=");
              System.out.println(nodeCur.lastPos().toString());
  
              dumpTree(((CMUniOp) nodeCur).getChild(), level + 1);
          } else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_LEAF) {
              System.out.print
                      (
                              "Leaf: (pos="
                                      + ((CMLeaf) nodeCur).getPosition()
                                      + "), "
                                      + ((CMLeaf) nodeCur).getElement()
                                      + "(elemIndex="
                                      + ((CMLeaf) nodeCur).getElement()
                                      + ") "
                      );
  
              if (nodeCur.isNullable())
                  System.out.print(" Nullable ");
  
              System.out.print("firstPos=");
              System.out.print(nodeCur.firstPos().toString());
              System.out.print(" lastPos=");
              System.out.println(nodeCur.lastPos().toString());
          } else {
              throw new RuntimeException("ImplementationMessages.VAL_NIICM");
          }
      }
  
  
      /**
       * -1 is used to represent bad transitions in the transition table
       * entry for each state. So each entry is initialized to an all -1
       * array. This method creates a new entry and initializes it.
       */
      private int[] makeDefStateList() {
          int[] retArray = new int[fElemMapSize];
          for (int index = 0; index < fElemMapSize; index++)
              retArray[index] = -1;
          return retArray;
      }
  
      /**
       * Post tree build initialization.
       */
      private int postTreeBuildInit(CMNode nodeCur, int curIndex) {
          // Set the maximum states on this node
          nodeCur.setMaxStates(fLeafCount);
  
          // Recurse as required
          if ((nodeCur.type() & 0x0f) == XMLContentSpec.CONTENTSPECNODE_ANY ||
                  (nodeCur.type() & 0x0f) == XMLContentSpec.CONTENTSPECNODE_ANY_LOCAL ||
                  (nodeCur.type() & 0x0f) == XMLContentSpec.CONTENTSPECNODE_ANY_OTHER) {
              // REVISIT: Don't waste these structures.
              QName qname = new QName(null, null, null, ((CMAny) nodeCur).getURI());
              fLeafList[curIndex] = new CMLeaf(qname, ((CMAny) nodeCur).getPosition());
              fLeafListType[curIndex] = nodeCur.type();
              curIndex++;
          } else if ((nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_CHOICE)
                  || (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_SEQ)) {
              curIndex = postTreeBuildInit(((CMBinOp) nodeCur).getLeft(), curIndex);
              curIndex = postTreeBuildInit(((CMBinOp) nodeCur).getRight(), curIndex);
          } else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ZERO_OR_MORE
                  || nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ONE_OR_MORE
                  || nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_ZERO_OR_ONE) {
              curIndex = postTreeBuildInit(((CMUniOp) nodeCur).getChild(), curIndex);
          } else if (nodeCur.type() == XMLContentSpec.CONTENTSPECNODE_LEAF) {
              //
              //  Put this node in the leaf list at the current index if its
              //  a non-epsilon leaf.
              //
              final QName node = ((CMLeaf) nodeCur).getElement();
              if (node.localpart != fEpsilonString) {
                  fLeafList[curIndex] = (CMLeaf) nodeCur;
                  fLeafListType[curIndex] = XMLContentSpec.CONTENTSPECNODE_LEAF;
                  curIndex++;
              }
          } else {
              throw new RuntimeException("ImplementationMessages.VAL_NIICM: type=" + nodeCur.type());
          }
          return curIndex;
      }
  
  } // class DFAContentModel
  