FileDocCategorySizeDatePackage
XSDFACM.javaAPI DocJava SE 5 API38654Fri Aug 26 14:55:52 BST 2005com.sun.org.apache.xerces.internal.impl.xs.models

XSDFACM

public class XSDFACM extends Object implements XSCMValidator
DFAContentModel is the implementation of XSCMValidator 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.
author
Neil Graham, IBM
version
$Id: XSDFACM.java,v 1.10 2003/04/30 20:24:49 sandygao Exp $

Fields Summary
private static final boolean
DEBUG
private static final boolean
DEBUG_VALIDATE_CONTENT
Set to true to debug content model validation.
private Object[]
fElemMap
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. Note tat since either XSElementDecl or XSParticleDecl object can live here, we've got to use an Object.
private int[]
fElemMapType
This is a map of whether the element map contains information related to ANY models.
private int[]
fElemMapId
id of the unique input symbol
private int
fElemMapSize
The element map size.
private boolean[]
fFinalStateFlags
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 CMStateSet[]
fFollowList
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 CMNode
fHeadNode
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 int
fLeafCount
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 XSCMLeaf[]
fLeafList
An array of non-epsilon leaf nodes, which is used during the DFA build operation, then dropped.
private int[]
fLeafListType
Array mapping ANY types to the leaf list.
private int[]
fTransTable
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.

The fElemMap array handles mapping from element indexes to positions in the second dimension of the transition table.

private int
fTransTableSize
The number of valid entries in the transition table, and in the other related tables such as fFinalStateFlags.
private static long
time
Constructors Summary
public XSDFACM(CMNode syntaxTree, int leafCount)
Constructs a DFA content model.

param
symbolTable The symbol table.
param
syntaxTree The syntax tree of the content model.
param
leafCount The number of leaves.
exception
RuntimeException Thrown if DFA can't be built.


    // temp variables

    //
    // Constructors
    //

                                                    

        
   
        // Store away our index and pools in members
        fLeafCount = leafCount;

        //
        //  Create some string pool indexes that represent the names of some
        //  magical nodes in the syntax tree.
        //  (already done in static initialization...
        //

        //
        //  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.
        //

        if(DEBUG_VALIDATE_CONTENT) {
            XSDFACM.time -= System.currentTimeMillis();
        }

        buildDFA(syntaxTree);

        if(DEBUG_VALIDATE_CONTENT) {
            XSDFACM.time += System.currentTimeMillis();
            System.out.println("DFA build: " + XSDFACM.time + "ms");
        }
Methods Summary
private voidbuildDFA(com.sun.org.apache.xerces.internal.impl.dtd.models.CMNode syntaxTree)
Builds the internal DFA transition table from the given syntax tree.

param
syntaxTree The syntax tree.
exception
RuntimeException Thrown if DFA cannot be built.

        //
        //  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+)+)+)+)+"
         */

        //
        //  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.
        //
        int EOCPos = fLeafCount;
        XSCMLeaf nodeEOC = new XSCMLeaf(XSParticleDecl.PARTICLE_ELEMENT, null, -1, fLeafCount++);
        fHeadNode = new XSCMBinOp(
            XSModelGroupImpl.MODELGROUP_SEQUENCE,
            syntaxTree,
            nodeEOC
        );

        //
        //  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 XSCMLeaf[fLeafCount];
        fLeafListType = new int[fLeafCount];
        postTreeBuildInit(fHeadNode);

        //
        //  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 Object[fLeafCount];
        fElemMapType = new int[fLeafCount];
        fElemMapId = new int[fLeafCount];
        fElemMapSize = 0;
        for (int outIndex = 0; outIndex < fLeafCount; outIndex++) {
            // optimization from Henry Zongaro:
            //fElemMap[outIndex] = new Object ();
            fElemMap[outIndex] = null;

            int inIndex = 0;
            final int id = fLeafList[outIndex].getParticleId();
            for (; inIndex < fElemMapSize; inIndex++) {
                if (id == fElemMapId[inIndex])
                    break;
            }

            // If it was not in the list, then add it, if not the EOC node
            if (inIndex == fElemMapSize) {
                fElemMap[fElemMapSize] = fLeafList[outIndex].getLeaf();
                fElemMapType[fElemMapSize] = fLeafListType[outIndex];
                fElemMapId[fElemMapSize] = id;
                fElemMapSize++;
            }
        }

        // the last entry in the element map must be the EOC element.
        // remove it from the map.
        if (DEBUG) {
            if (fElemMapId[fElemMapSize-1] != -1)
                System.err.println("interal error in DFA: last element is not EOC.");
        }
        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++) {
            final int id = fElemMapId[elemIndex];
            for (int leafIndex = 0; leafIndex < fLeafCount; leafIndex++) {
                if (id == fLeafList[leafIndex].getParticleId())
                    fLeafSorter[fSortCount++] = leafIndex;
            }
            fLeafSorter[fSortCount++] = -1;
        }

        /* Optimization(Jan, 2001) */

        //
        //  Next lets create some arrays, some 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+)".
         */

        java.util.Hashtable stateTable = new java.util.Hashtable();

        /* 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(EOCPos);

            // 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
                        for (int expIndex = 0; expIndex < curArraySize; expIndex++) {
                            newToDo[expIndex] = statesToDo[expIndex];
                            newFinalFlags[expIndex] = fFinalStateFlags[expIndex];
                            newTransTable[expIndex] = fTransTable[expIndex];
                        }

                        // Store the new array size
                        curArraySize = newSize;
                        statesToDo = newToDo;
                        fFinalStateFlags = newFinalFlags;
                        fTransTable = newTransTable;
                    }
                }
            }
        }

        //
        //  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;
        fLeafListType = null;
        fElemMapId = null;
private voidcalcFollowList(com.sun.org.apache.xerces.internal.impl.dtd.models.CMNode nodeCur)
Calculates the follow list of the current node.

param
nodeCur The curent node.
exception
RuntimeException Thrown if follow list cannot be calculated.

        // Recurse as required
        if (nodeCur.type() == XSModelGroupImpl.MODELGROUP_CHOICE) {
            // Recurse only
            calcFollowList(((XSCMBinOp)nodeCur).getLeft());
            calcFollowList(((XSCMBinOp)nodeCur).getRight());
        }
         else if (nodeCur.type() == XSModelGroupImpl.MODELGROUP_SEQUENCE) {
            // Recurse first
            calcFollowList(((XSCMBinOp)nodeCur).getLeft());
            calcFollowList(((XSCMBinOp)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  = ((XSCMBinOp)nodeCur).getLeft().lastPos();
            final CMStateSet first = ((XSCMBinOp)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() == XSParticleDecl.PARTICLE_ZERO_OR_MORE
        || nodeCur.type() == XSParticleDecl.PARTICLE_ONE_OR_MORE) {
            // Recurse first
            calcFollowList(((XSCMUniOp)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() == XSParticleDecl.PARTICLE_ZERO_OR_ONE) {
            // Recurse only
            calcFollowList(((XSCMUniOp)nodeCur).getChild());
        }
public booleancheckUniqueParticleAttribution(com.sun.org.apache.xerces.internal.impl.xs.SubstitutionGroupHandler subGroupHandler)
check whether this content violates UPA constraint.

param
errors to hold the UPA errors
return
true if this content model contains other or list wildcard

        // Unique Particle Attribution
        // store the conflict results between any two elements in fElemMap
        // 0: not compared; -1: no conflict; 1: conflict
        // initialize the conflict table (all 0 initially)
        byte conflictTable[][] = new byte[fElemMapSize][fElemMapSize];

        // for each state, check whether it has overlap transitions
        for (int i = 0; i < fTransTable.length && fTransTable[i] != null; i++) {
            for (int j = 0; j < fElemMapSize; j++) {
                for (int k = j+1; k < fElemMapSize; k++) {
                    if (fTransTable[i][j] != -1 &&
                        fTransTable[i][k] != -1) {
                        if (conflictTable[j][k] == 0) {
                            conflictTable[j][k] = XSConstraints.overlapUPA
                                                   (fElemMap[j],fElemMap[k],
                                                   subGroupHandler) ?
                                                   (byte)1 : (byte)-1;
                        }
                    }
                }
            }
        }

        // report all errors
        for (int i = 0; i < fElemMapSize; i++) {
            for (int j = 0; j < fElemMapSize; j++) {
                if (conflictTable[i][j] == 1) {
                    //errors.newError("cos-nonambig", new Object[]{fElemMap[i].toString(),
                    //                                             fElemMap[j].toString()});
                    // REVISIT: do we want to report all errors? or just one?
                    throw new XMLSchemaException("cos-nonambig", new Object[]{fElemMap[i].toString(),
                                                                              fElemMap[j].toString()});
                }
            }
        }

        // if there is a other or list wildcard, we need to check this CM
        // again, if this grammar is cached.
        for (int i = 0; i < fElemMapSize; i++) {
            if (fElemMapType[i] == XSParticleDecl.PARTICLE_WILDCARD) {
                XSWildcardDecl wildcard = (XSWildcardDecl)fElemMap[i];
                if (wildcard.fType == XSWildcardDecl.NSCONSTRAINT_LIST ||
                    wildcard.fType == XSWildcardDecl.NSCONSTRAINT_NOT) {
                    return true;
                }
            }
        }

        return false;
private voiddumpTree(com.sun.org.apache.xerces.internal.impl.dtd.models.CMNode nodeCur, int level)
Dumps the tree of the current node to standard output.

param
nodeCur The current node.
param
level The maximum levels to output.
exception
RuntimeException Thrown on error.

        for (int index = 0; index < level; index++)
            System.out.print("   ");

        int type = nodeCur.type();

        switch(type ) {

        case XSModelGroupImpl.MODELGROUP_CHOICE:
        case XSModelGroupImpl.MODELGROUP_SEQUENCE: {
            if (type == XSModelGroupImpl.MODELGROUP_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(((XSCMBinOp)nodeCur).getLeft(), level+1);
            dumpTree(((XSCMBinOp)nodeCur).getRight(), level+1);
            break;
        }
        case XSParticleDecl.PARTICLE_ZERO_OR_MORE:
        case XSParticleDecl.PARTICLE_ONE_OR_MORE:
        case XSParticleDecl.PARTICLE_ZERO_OR_ONE: {
            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(((XSCMUniOp)nodeCur).getChild(), level+1);
            break;
        }
        case XSParticleDecl.PARTICLE_ELEMENT: {
            System.out.print
            (
                "Leaf: (pos="
                + ((XSCMLeaf)nodeCur).getPosition()
                + "), "
                + "(elemIndex="
                + ((XSCMLeaf)nodeCur).getLeaf()
                + ") "
            );

            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());
            break;
        }
        case XSParticleDecl.PARTICLE_WILDCARD:
              System.out.print("Any Node: ");

            System.out.print("firstPos=");
            System.out.print(nodeCur.firstPos().toString());
            System.out.print(" lastPos=");
            System.out.println(nodeCur.lastPos().toString());
            break;
        default: {
            throw new RuntimeException("ImplementationMessages.VAL_NIICM");
        }
        }
public booleanendContentModel(int[] state)

        return fFinalStateFlags[state[0]];
java.lang.ObjectfindMatchingDecl(com.sun.org.apache.xerces.internal.xni.QName curElem, com.sun.org.apache.xerces.internal.impl.xs.SubstitutionGroupHandler subGroupHandler)

        Object matchingDecl = null;

        for (int elemIndex = 0; elemIndex < fElemMapSize; elemIndex++) {
            int type = fElemMapType[elemIndex] ;
            if (type == XSParticleDecl.PARTICLE_ELEMENT) {
                matchingDecl = subGroupHandler.getMatchingElemDecl(curElem, (XSElementDecl)fElemMap[elemIndex]);
                if (matchingDecl != null) {
                    return matchingDecl;
                }
            }
            else if (type == XSParticleDecl.PARTICLE_WILDCARD) {
                if(((XSWildcardDecl)fElemMap[elemIndex]).allowNamespace(curElem.uri))
                    return fElemMap[elemIndex];
            }
        }

        return null;
public booleanisFinalState(int state)
check whether the given state is one of the final states

param
state the state to check
return
whether it's a final state


    //
    // XSCMValidator methods
    //

                                      
         
        return (state < 0)? false :
            fFinalStateFlags[state];
private int[]makeDefStateList()
-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.

        int[] retArray = new int[fElemMapSize];
        for (int index = 0; index < fElemMapSize; index++)
            retArray[index] = -1;
        return retArray;
public java.lang.ObjectoneTransition(com.sun.org.apache.xerces.internal.xni.QName curElem, int[] state, com.sun.org.apache.xerces.internal.impl.xs.SubstitutionGroupHandler subGroupHandler)
one transition only

param
curElem The current element's QName
param
stateStack stack to store the previous state
param
curPos the current position of the stack
return
null if transition is invalid; otherwise the Object corresponding to the XSElementDecl or XSWildcardDecl identified. Also, the state array will be modified to include the new state; this so that the validator can store it away.
exception
RuntimeException thrown on error

        int curState = state[0];

        if(curState == XSCMValidator.FIRST_ERROR || curState == XSCMValidator.SUBSEQUENT_ERROR) {
            // there was an error last time; so just go find correct Object in fElemmMap.
            // ... after resetting state[0].
            if(curState == XSCMValidator.FIRST_ERROR)
                state[0] = XSCMValidator.SUBSEQUENT_ERROR;

            return findMatchingDecl(curElem, subGroupHandler);
        }

        int nextState = 0;
        int elemIndex = 0;
        Object matchingDecl = null;

        for (; elemIndex < fElemMapSize; elemIndex++) {
            nextState = fTransTable[curState][elemIndex];
            if (nextState == -1)
                continue;
            int type = fElemMapType[elemIndex] ;
            if (type == XSParticleDecl.PARTICLE_ELEMENT) {
                matchingDecl = subGroupHandler.getMatchingElemDecl(curElem, (XSElementDecl)fElemMap[elemIndex]);
                if (matchingDecl != null) {
                    break;
                }
            }
            else if (type == XSParticleDecl.PARTICLE_WILDCARD) {
                if(((XSWildcardDecl)fElemMap[elemIndex]).allowNamespace(curElem.uri)) {
                    matchingDecl = fElemMap[elemIndex];
                    break;
                }
            }
        }

        // if we still can't find a match, set the state to first_error
        // and return null
        if (elemIndex == fElemMapSize) {
            state[1] = state[0];
            state[0] = XSCMValidator.FIRST_ERROR;
            return findMatchingDecl(curElem, subGroupHandler);
        }

        state[0] = nextState;
        return matchingDecl;
private voidpostTreeBuildInit(com.sun.org.apache.xerces.internal.impl.dtd.models.CMNode nodeCur)
Post tree build initialization.

        // Set the maximum states on this node
        nodeCur.setMaxStates(fLeafCount);

        XSCMLeaf leaf = null;
        int pos = 0;
        // Recurse as required
        if (nodeCur.type() == XSParticleDecl.PARTICLE_WILDCARD) {
            leaf = (XSCMLeaf)nodeCur;
            pos = leaf.getPosition();
            fLeafList[pos] = leaf;
            fLeafListType[pos] = XSParticleDecl.PARTICLE_WILDCARD;
        }
        else if ((nodeCur.type() == XSModelGroupImpl.MODELGROUP_CHOICE) ||
                 (nodeCur.type() == XSModelGroupImpl.MODELGROUP_SEQUENCE)) {
            postTreeBuildInit(((XSCMBinOp)nodeCur).getLeft());
            postTreeBuildInit(((XSCMBinOp)nodeCur).getRight());
        }
        else if (nodeCur.type() == XSParticleDecl.PARTICLE_ZERO_OR_MORE ||
                 nodeCur.type() == XSParticleDecl.PARTICLE_ONE_OR_MORE ||
                 nodeCur.type() == XSParticleDecl.PARTICLE_ZERO_OR_ONE) {
            postTreeBuildInit(((XSCMUniOp)nodeCur).getChild());
        }
        else if (nodeCur.type() == XSParticleDecl.PARTICLE_ELEMENT) {
            //  Put this node in the leaf list at the current index if its
            //  a non-epsilon leaf.
            leaf = (XSCMLeaf)nodeCur;
            pos = leaf.getPosition();
            fLeafList[pos] = leaf;
            fLeafListType[pos] = XSParticleDecl.PARTICLE_ELEMENT;
        }
        else {
            throw new RuntimeException("ImplementationMessages.VAL_NIICM");
        }
public int[]startContentModel()

        int[] val = new int[2];
        val[0] = 0;
        return val;
public java.util.VectorwhatCanGoHere(int[] state)
Check which elements are valid to appear at this point. This method also works if the state is in error, in which case it returns what should have been seen.

param
state the current state
return
a Vector whose entries are instances of either XSWildcardDecl or XSElementDecl.

        int curState = state[0];
        if (curState < 0)
            curState = state[1];

        Vector ret = new Vector();
        for (int elemIndex = 0; elemIndex < fElemMapSize; elemIndex++) {
            if (fTransTable[curState][elemIndex] != -1)
                ret.addElement(fElemMap[elemIndex]);
        }
        return ret;