001// NamespaceSupport.java - generic Namespace support for SAX.
002// http://www.saxproject.org
003// Written by David Megginson
004// This class is in the Public Domain.  NO WARRANTY!
005// $Id: NamespaceSupport.java,v 1.1 2004/12/23 22:38:42 mark Exp $
006
007package org.xml.sax.helpers;
008
009import java.util.EmptyStackException;
010import java.util.Enumeration;
011import java.util.Hashtable;
012import java.util.Vector;
013
014
015/**
016 * Encapsulate Namespace logic for use by applications using SAX,
017 * or internally by SAX drivers.
018 *
019 * <blockquote>
020 * <em>This module, both source code and documentation, is in the
021 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
022 * See <a href='http://www.saxproject.org'>http://www.saxproject.org</a>
023 * for further information.
024 * </blockquote>
025 *
026 * <p>This class encapsulates the logic of Namespace processing: it
027 * tracks the declarations currently in force for each context and
028 * automatically processes qualified XML names into their Namespace
029 * parts; it can also be used in reverse for generating XML qnames
030 * from Namespaces.</p>
031 *
032 * <p>Namespace support objects are reusable, but the reset method
033 * must be invoked between each session.</p>
034 *
035 * <p>Here is a simple session:</p>
036 *
037 * <pre>
038 * String parts[] = new String[3];
039 * NamespaceSupport support = new NamespaceSupport();
040 *
041 * support.pushContext();
042 * support.declarePrefix("", "http://www.w3.org/1999/xhtml");
043 * support.declarePrefix("dc", "http://www.purl.org/dc#");
044 *
045 * parts = support.processName("p", parts, false);
046 * System.out.println("Namespace URI: " + parts[0]);
047 * System.out.println("Local name: " + parts[1]);
048 * System.out.println("Raw name: " + parts[2]);
049 *
050 * parts = support.processName("dc:title", parts, false);
051 * System.out.println("Namespace URI: " + parts[0]);
052 * System.out.println("Local name: " + parts[1]);
053 * System.out.println("Raw name: " + parts[2]);
054 *
055 * support.popContext();
056 * </pre>
057 *
058 * <p>Note that this class is optimized for the use case where most
059 * elements do not contain Namespace declarations: if the same
060 * prefix/URI mapping is repeated for each context (for example), this
061 * class will be somewhat less efficient.</p>
062 *
063 * <p>Although SAX drivers (parsers) may choose to use this class to
064 * implement namespace handling, they are not required to do so.
065 * Applications must track namespace information themselves if they
066 * want to use namespace information.
067 *
068 * @since SAX 2.0
069 * @author David Megginson
070 * @version 2.0.1 (sax2r2)
071 */
072public class NamespaceSupport
073{
074
075
076    ////////////////////////////////////////////////////////////////////
077    // Constants.
078    ////////////////////////////////////////////////////////////////////
079
080
081    /**
082     * The XML Namespace URI as a constant.
083     * The value is <code>http://www.w3.org/XML/1998/namespace</code>
084     * as defined in the "Namespaces in XML" * recommendation.
085     *
086     * <p>This is the Namespace URI that is automatically mapped
087     * to the "xml" prefix.</p>
088     */
089    public final static String XMLNS =
090        "http://www.w3.org/XML/1998/namespace";
091
092
093    /**
094     * The namespace declaration URI as a constant.
095     * The value is <code>http://www.w3.org/xmlns/2000/</code>, as defined
096     * in a backwards-incompatible erratum to the "Namespaces in XML"
097     * recommendation.  Because that erratum postdated SAX2, SAX2 defaults
098     * to the original recommendation, and does not normally use this URI.
099     *
100     *
101     * <p>This is the Namespace URI that is optionally applied to
102     * <em>xmlns</em> and <em>xmlns:*</em> attributes, which are used to
103     * declare namespaces.  </p>
104     *
105     * @since SAX 2.1alpha
106     * @see #setNamespaceDeclUris
107     * @see #isNamespaceDeclUris
108     */
109    public final static String NSDECL =
110        "http://www.w3.org/xmlns/2000/";
111
112
113    /**
114     * An empty enumeration.
115     */
116    private final static Enumeration EMPTY_ENUMERATION =
117        new Vector().elements();
118
119
120    ////////////////////////////////////////////////////////////////////
121    // Constructor.
122    ////////////////////////////////////////////////////////////////////
123
124
125    /**
126     * Create a new Namespace support object.
127     */
128    public NamespaceSupport ()
129    {
130        reset();
131    }
132
133
134
135    ////////////////////////////////////////////////////////////////////
136    // Context management.
137    ////////////////////////////////////////////////////////////////////
138
139
140    /**
141     * Reset this Namespace support object for reuse.
142     *
143     * <p>It is necessary to invoke this method before reusing the
144     * Namespace support object for a new session.  If namespace
145     * declaration URIs are to be supported, that flag must also
146     * be set to a non-default value.
147     * </p>
148     *
149     * @see #setNamespaceDeclUris
150     */
151    public void reset ()
152    {
153        contexts = new Context[32];
154        namespaceDeclUris = false;
155        contextPos = 0;
156        contexts[contextPos] = currentContext = new Context();
157        currentContext.declarePrefix("xml", XMLNS);
158    }
159
160
161    /**
162     * Start a new Namespace context.
163     * The new context will automatically inherit
164     * the declarations of its parent context, but it will also keep
165     * track of which declarations were made within this context.
166     *
167     * <p>Event callback code should start a new context once per element.
168     * This means being ready to call this in either of two places.
169     * For elements that don't include namespace declarations, the
170     * <em>ContentHandler.startElement()</em> callback is the right place.
171     * For elements with such a declaration, it'd done in the first
172     * <em>ContentHandler.startPrefixMapping()</em> callback.
173     * A boolean flag can be used to
174     * track whether a context has been started yet.  When either of
175     * those methods is called, it checks the flag to see if a new context
176     * needs to be started.  If so, it starts the context and sets the
177     * flag.  After <em>ContentHandler.startElement()</em>
178     * does that, it always clears the flag.
179     *
180     * <p>Normally, SAX drivers would push a new context at the beginning
181     * of each XML element.  Then they perform a first pass over the
182     * attributes to process all namespace declarations, making
183     * <em>ContentHandler.startPrefixMapping()</em> callbacks.
184     * Then a second pass is made, to determine the namespace-qualified
185     * names for all attributes and for the element name.
186     * Finally all the information for the
187     * <em>ContentHandler.startElement()</em> callback is available,
188     * so it can then be made.
189     *
190     * <p>The Namespace support object always starts with a base context
191     * already in force: in this context, only the "xml" prefix is
192     * declared.</p>
193     *
194     * @see org.xml.sax.ContentHandler
195     * @see #popContext
196     */
197    public void pushContext ()
198    {
199        int max = contexts.length;
200
201        contexts [contextPos].declsOK = false;
202        contextPos++;
203
204                                // Extend the array if necessary
205        if (contextPos >= max) {
206            Context newContexts[] = new Context[max*2];
207            System.arraycopy(contexts, 0, newContexts, 0, max);
208            max *= 2;
209            contexts = newContexts;
210        }
211
212                                // Allocate the context if necessary.
213        currentContext = contexts[contextPos];
214        if (currentContext == null) {
215            contexts[contextPos] = currentContext = new Context();
216        }
217
218                                // Set the parent, if any.
219        if (contextPos > 0) {
220            currentContext.setParent(contexts[contextPos - 1]);
221        }
222    }
223
224
225    /**
226     * Revert to the previous Namespace context.
227     *
228     * <p>Normally, you should pop the context at the end of each
229     * XML element.  After popping the context, all Namespace prefix
230     * mappings that were previously in force are restored.</p>
231     *
232     * <p>You must not attempt to declare additional Namespace
233     * prefixes after popping a context, unless you push another
234     * context first.</p>
235     *
236     * @see #pushContext
237     */
238    public void popContext ()
239    {
240        contexts[contextPos].clear();
241        contextPos--;
242        if (contextPos < 0) {
243            throw new EmptyStackException();
244        }
245        currentContext = contexts[contextPos];
246    }
247
248
249
250    ////////////////////////////////////////////////////////////////////
251    // Operations within a context.
252    ////////////////////////////////////////////////////////////////////
253
254
255    /**
256     * Declare a Namespace prefix.  All prefixes must be declared
257     * before they are referenced.  For example, a SAX driver (parser)
258     * would scan an element's attributes
259     * in two passes:  first for namespace declarations,
260     * then a second pass using {@link #processName processName()} to
261     * interpret prefixes against (potentially redefined) prefixes.
262     *
263     * <p>This method declares a prefix in the current Namespace
264     * context; the prefix will remain in force until this context
265     * is popped, unless it is shadowed in a descendant context.</p>
266     *
267     * <p>To declare the default element Namespace, use the empty string as
268     * the prefix.</p>
269     *
270     * <p>Note that you must <em>not</em> declare a prefix after
271     * you've pushed and popped another Namespace context, or
272     * treated the declarations phase as complete by processing
273     * a prefixed name.</p>
274     *
275     * <p>Note that there is an asymmetry in this library: {@link
276     * #getPrefix getPrefix} will not return the "" prefix,
277     * even if you have declared a default element namespace.
278     * To check for a default namespace,
279     * you have to look it up explicitly using {@link #getURI getURI}.
280     * This asymmetry exists to make it easier to look up prefixes
281     * for attribute names, where the default prefix is not allowed.</p>
282     *
283     * @param prefix The prefix to declare, or the empty string to
284     *  indicate the default element namespace.  This may never have
285     *  the value "xml" or "xmlns".
286     * @param uri The Namespace URI to associate with the prefix.
287     * @return true if the prefix was legal, false otherwise
288     *
289     * @see #processName
290     * @see #getURI
291     * @see #getPrefix
292     */
293    public boolean declarePrefix (String prefix, String uri)
294    {
295        if (prefix.equals("xml") || prefix.equals("xmlns")) {
296            return false;
297        } else {
298            currentContext.declarePrefix(prefix, uri);
299            return true;
300        }
301    }
302
303
304    /**
305     * Process a raw XML qualified name, after all declarations in the
306     * current context have been handled by {@link #declarePrefix
307     * declarePrefix()}.
308     *
309     * <p>This method processes a raw XML qualified name in the
310     * current context by removing the prefix and looking it up among
311     * the prefixes currently declared.  The return value will be the
312     * array supplied by the caller, filled in as follows:</p>
313     *
314     * <dl>
315     * <dt>parts[0]</dt>
316     * <dd>The Namespace URI, or an empty string if none is
317     *  in use.</dd>
318     * <dt>parts[1]</dt>
319     * <dd>The local name (without prefix).</dd>
320     * <dt>parts[2]</dt>
321     * <dd>The original raw name.</dd>
322     * </dl>
323     *
324     * <p>All of the strings in the array will be internalized.  If
325     * the raw name has a prefix that has not been declared, then
326     * the return value will be null.</p>
327     *
328     * <p>Note that attribute names are processed differently than
329     * element names: an unprefixed element name will receive the
330     * default Namespace (if any), while an unprefixed attribute name
331     * will not.</p>
332     *
333     * @param qName The XML qualified name to be processed.
334     * @param parts An array supplied by the caller, capable of
335     *        holding at least three members.
336     * @param isAttribute A flag indicating whether this is an
337     *        attribute name (true) or an element name (false).
338     * @return The supplied array holding three internalized strings
339     *        representing the Namespace URI (or empty string), the
340     *        local name, and the XML qualified name; or null if there
341     *        is an undeclared prefix.
342     * @see #declarePrefix
343     * @see java.lang.String#intern */
344    public String [] processName (String qName, String parts[],
345                                  boolean isAttribute)
346    {
347        String myParts[] = currentContext.processName(qName, isAttribute);
348        if (myParts == null) {
349            return null;
350        } else {
351            parts[0] = myParts[0];
352            parts[1] = myParts[1];
353            parts[2] = myParts[2];
354            return parts;
355        }
356    }
357
358
359    /**
360     * Look up a prefix and get the currently-mapped Namespace URI.
361     *
362     * <p>This method looks up the prefix in the current context.
363     * Use the empty string ("") for the default Namespace.</p>
364     *
365     * @param prefix The prefix to look up.
366     * @return The associated Namespace URI, or null if the prefix
367     *         is undeclared in this context.
368     * @see #getPrefix
369     * @see #getPrefixes
370     */
371    public String getURI (String prefix)
372    {
373        return currentContext.getURI(prefix);
374    }
375
376
377    /**
378     * Return an enumeration of all prefixes whose declarations are
379     * active in the current context.
380     * This includes declarations from parent contexts that have
381     * not been overridden.
382     *
383     * <p><strong>Note:</strong> if there is a default prefix, it will not be
384     * returned in this enumeration; check for the default prefix
385     * using the {@link #getURI getURI} with an argument of "".</p>
386     *
387     * @return An enumeration of prefixes (never empty).
388     * @see #getDeclaredPrefixes
389     * @see #getURI
390     */
391    public Enumeration getPrefixes ()
392    {
393        return currentContext.getPrefixes();
394    }
395
396
397    /**
398     * Return one of the prefixes mapped to a Namespace URI.
399     *
400     * <p>If more than one prefix is currently mapped to the same
401     * URI, this method will make an arbitrary selection; if you
402     * want all of the prefixes, use the {@link #getPrefixes}
403     * method instead.</p>
404     *
405     * <p><strong>Note:</strong> this will never return the empty (default) prefix;
406     * to check for a default prefix, use the {@link #getURI getURI}
407     * method with an argument of "".</p>
408     *
409     * @param uri the namespace URI
410     * @return one of the prefixes currently mapped to the URI supplied,
411     *         or null if none is mapped or if the URI is assigned to
412     *         the default namespace
413     * @see #getPrefixes(java.lang.String)
414     * @see #getURI
415     */
416    public String getPrefix (String uri)
417    {
418        return currentContext.getPrefix(uri);
419    }
420
421
422    /**
423     * Return an enumeration of all prefixes for a given URI whose
424     * declarations are active in the current context.
425     * This includes declarations from parent contexts that have
426     * not been overridden.
427     *
428     * <p>This method returns prefixes mapped to a specific Namespace
429     * URI.  The xml: prefix will be included.  If you want only one
430     * prefix that's mapped to the Namespace URI, and you don't care
431     * which one you get, use the {@link #getPrefix getPrefix}
432     *  method instead.</p>
433     *
434     * <p><strong>Note:</strong> the empty (default) prefix is <em>never</em> included
435     * in this enumeration; to check for the presence of a default
436     * Namespace, use the {@link #getURI getURI} method with an
437     * argument of "".</p>
438     *
439     * @param uri The Namespace URI.
440     * @return An enumeration of prefixes (never empty).
441     * @see #getPrefix
442     * @see #getDeclaredPrefixes
443     * @see #getURI
444     */
445    public Enumeration getPrefixes (String uri)
446    {
447        Vector prefixes = new Vector();
448        Enumeration allPrefixes = getPrefixes();
449        while (allPrefixes.hasMoreElements()) {
450            String prefix = (String)allPrefixes.nextElement();
451            if (uri.equals(getURI(prefix))) {
452                prefixes.addElement(prefix);
453            }
454        }
455        return prefixes.elements();
456    }
457
458
459    /**
460     * Return an enumeration of all prefixes declared in this context.
461     *
462     * <p>The empty (default) prefix will be included in this
463     * enumeration; note that this behaviour differs from that of
464     * {@link #getPrefix} and {@link #getPrefixes}.</p>
465     *
466     * @return An enumeration of all prefixes declared in this
467     *         context.
468     * @see #getPrefixes
469     * @see #getURI
470     */
471    public Enumeration getDeclaredPrefixes ()
472    {
473        return currentContext.getDeclaredPrefixes();
474    }
475
476    /**
477     * Controls whether namespace declaration attributes are placed
478     * into the {@link #NSDECL NSDECL} namespace
479     * by {@link #processName processName()}.  This may only be
480     * changed before any contexts have been pushed.
481     *
482     * @since SAX 2.1alpha
483     *
484     * @exception IllegalStateException when attempting to set this
485     *  after any context has been pushed.
486     */
487    public void setNamespaceDeclUris (boolean value)
488    {
489        if (contextPos != 0)
490            throw new IllegalStateException ();
491        if (value == namespaceDeclUris)
492            return;
493        namespaceDeclUris = value;
494        if (value)
495            currentContext.declarePrefix ("xmlns", NSDECL);
496        else {
497            contexts[contextPos] = currentContext = new Context();
498            currentContext.declarePrefix("xml", XMLNS);
499        }
500    }
501
502    /**
503     * Returns true if namespace declaration attributes are placed into
504     * a namespace.  This behavior is not the default.
505     *
506     * @since SAX 2.1alpha
507     */
508    public boolean isNamespaceDeclUris ()
509        { return namespaceDeclUris; }
510
511
512
513    ////////////////////////////////////////////////////////////////////
514    // Internal state.
515    ////////////////////////////////////////////////////////////////////
516
517    private Context contexts[];
518    private Context currentContext;
519    private int contextPos;
520    private boolean namespaceDeclUris;
521
522
523    ////////////////////////////////////////////////////////////////////
524    // Internal classes.
525    ////////////////////////////////////////////////////////////////////
526
527    /**
528     * Internal class for a single Namespace context.
529     *
530     * <p>This module caches and reuses Namespace contexts,
531     * so the number allocated
532     * will be equal to the element depth of the document, not to the total
533     * number of elements (i.e. 5-10 rather than tens of thousands).
534     * Also, data structures used to represent contexts are shared when
535     * possible (child contexts without declarations) to further reduce
536     * the amount of memory that's consumed.
537     * </p>
538     */
539    final class Context {
540
541        /**
542         * Create the root-level Namespace context.
543         */
544        Context ()
545        {
546            copyTables();
547        }
548
549
550        /**
551         * (Re)set the parent of this Namespace context.
552         * The context must either have been freshly constructed,
553         * or must have been cleared.
554         *
555         * @param context The parent Namespace context object.
556         */
557        void setParent (Context parent)
558        {
559            this.parent = parent;
560            declarations = null;
561            prefixTable = parent.prefixTable;
562            uriTable = parent.uriTable;
563            elementNameTable = parent.elementNameTable;
564            attributeNameTable = parent.attributeNameTable;
565            defaultNS = parent.defaultNS;
566            declSeen = false;
567            declsOK = true;
568        }
569
570        /**
571         * Makes associated state become collectible,
572         * invalidating this context.
573         * {@link #setParent} must be called before
574         * this context may be used again.
575         */
576        void clear ()
577        {
578            parent = null;
579            prefixTable = null;
580            uriTable = null;
581            elementNameTable = null;
582            attributeNameTable = null;
583            defaultNS = null;
584        }
585
586
587        /**
588         * Declare a Namespace prefix for this context.
589         *
590         * @param prefix The prefix to declare.
591         * @param uri The associated Namespace URI.
592         * @see org.xml.sax.helpers.NamespaceSupport#declarePrefix
593         */
594        void declarePrefix (String prefix, String uri)
595        {
596                                // Lazy processing...
597            if (!declsOK)
598                throw new IllegalStateException (
599                    "can't declare any more prefixes in this context");
600            if (!declSeen) {
601                copyTables();
602            }
603            if (declarations == null) {
604                declarations = new Vector();
605            }
606
607            prefix = prefix.intern();
608            uri = uri.intern();
609            if ("".equals(prefix)) {
610                if ("".equals(uri)) {
611                    defaultNS = null;
612                } else {
613                    defaultNS = uri;
614                }
615            } else {
616                prefixTable.put(prefix, uri);
617                uriTable.put(uri, prefix); // may wipe out another prefix
618            }
619            declarations.addElement(prefix);
620        }
621
622
623        /**
624         * Process an XML qualified name in this context.
625         *
626         * @param qName The XML qualified name.
627         * @param isAttribute true if this is an attribute name.
628         * @return An array of three strings containing the
629         *         URI part (or empty string), the local part,
630         *         and the raw name, all internalized, or null
631         *         if there is an undeclared prefix.
632         * @see org.xml.sax.helpers.NamespaceSupport#processName
633         */
634        String [] processName (String qName, boolean isAttribute)
635        {
636            String name[];
637            Hashtable table;
638
639                                // detect errors in call sequence
640            declsOK = false;
641
642                                // Select the appropriate table.
643            if (isAttribute) {
644                table = attributeNameTable;
645            } else {
646                table = elementNameTable;
647            }
648
649                                // Start by looking in the cache, and
650                                // return immediately if the name
651                                // is already known in this content
652            name = (String[])table.get(qName);
653            if (name != null) {
654                return name;
655            }
656
657                                // We haven't seen this name in this
658                                // context before.  Maybe in the parent
659                                // context, but we can't assume prefix
660                                // bindings are the same.
661            name = new String[3];
662            name[2] = qName.intern();
663            int index = qName.indexOf(':');
664
665
666                                // No prefix.
667            if (index == -1) {
668                if (isAttribute) {
669                    if (qName == "xmlns" && namespaceDeclUris)
670                        name[0] = NSDECL;
671                    else
672                        name[0] = "";
673                } else if (defaultNS == null) {
674                    name[0] = "";
675                } else {
676                    name[0] = defaultNS;
677                }
678                name[1] = name[2];
679            }
680
681                                // Prefix
682            else {
683                String prefix = qName.substring(0, index);
684                String local = qName.substring(index+1);
685                String uri;
686                if ("".equals(prefix)) {
687                    uri = defaultNS;
688                } else {
689                    uri = (String)prefixTable.get(prefix);
690                }
691                if (uri == null
692                        || (!isAttribute && "xmlns".equals (prefix))) {
693                    return null;
694                }
695                name[0] = uri;
696                name[1] = local.intern();
697            }
698
699                                // Save in the cache for future use.
700                                // (Could be shared with parent context...)
701            table.put(name[2], name);
702            return name;
703        }
704
705
706        /**
707         * Look up the URI associated with a prefix in this context.
708         *
709         * @param prefix The prefix to look up.
710         * @return The associated Namespace URI, or null if none is
711         *         declared.
712         * @see org.xml.sax.helpers.NamespaceSupport#getURI
713         */
714        String getURI (String prefix)
715        {
716            if ("".equals(prefix)) {
717                return defaultNS;
718            } else if (prefixTable == null) {
719                return null;
720            } else {
721                return (String)prefixTable.get(prefix);
722            }
723        }
724
725
726        /**
727         * Look up one of the prefixes associated with a URI in this context.
728         *
729         * <p>Since many prefixes may be mapped to the same URI,
730         * the return value may be unreliable.</p>
731         *
732         * @param uri The URI to look up.
733         * @return The associated prefix, or null if none is declared.
734         * @see org.xml.sax.helpers.NamespaceSupport#getPrefix
735         */
736        String getPrefix (String uri)
737        {
738            if (uriTable == null) {
739                return null;
740            } else {
741                return (String)uriTable.get(uri);
742            }
743        }
744
745
746        /**
747         * Return an enumeration of prefixes declared in this context.
748         *
749         * @return An enumeration of prefixes (possibly empty).
750         * @see org.xml.sax.helpers.NamespaceSupport#getDeclaredPrefixes
751         */
752        Enumeration getDeclaredPrefixes ()
753        {
754            if (declarations == null) {
755                return EMPTY_ENUMERATION;
756            } else {
757                return declarations.elements();
758            }
759        }
760
761
762        /**
763         * Return an enumeration of all prefixes currently in force.
764         *
765         * <p>The default prefix, if in force, is <em>not</em>
766         * returned, and will have to be checked for separately.</p>
767         *
768         * @return An enumeration of prefixes (never empty).
769         * @see org.xml.sax.helpers.NamespaceSupport#getPrefixes
770         */
771        Enumeration getPrefixes ()
772        {
773            if (prefixTable == null) {
774                return EMPTY_ENUMERATION;
775            } else {
776                return prefixTable.keys();
777            }
778        }
779
780
781
782        ////////////////////////////////////////////////////////////////
783        // Internal methods.
784        ////////////////////////////////////////////////////////////////
785
786
787        /**
788         * Copy on write for the internal tables in this context.
789         *
790         * <p>This class is optimized for the normal case where most
791         * elements do not contain Namespace declarations.</p>
792         */
793        private void copyTables ()
794        {
795            if (prefixTable != null) {
796                prefixTable = (Hashtable)prefixTable.clone();
797            } else {
798                prefixTable = new Hashtable();
799            }
800            if (uriTable != null) {
801                uriTable = (Hashtable)uriTable.clone();
802            } else {
803                uriTable = new Hashtable();
804            }
805            elementNameTable = new Hashtable();
806            attributeNameTable = new Hashtable();
807            declSeen = true;
808        }
809
810
811
812        ////////////////////////////////////////////////////////////////
813        // Protected state.
814        ////////////////////////////////////////////////////////////////
815
816        Hashtable prefixTable;
817        Hashtable uriTable;
818        Hashtable elementNameTable;
819        Hashtable attributeNameTable;
820        String defaultNS = null;
821        boolean declsOK = true;
822
823
824
825        ////////////////////////////////////////////////////////////////
826        // Internal state.
827        ////////////////////////////////////////////////////////////////
828
829        private Vector declarations = null;
830        private boolean declSeen = false;
831        private Context parent = null;
832    }
833}
834
835// end of NamespaceSupport.java