// ParserAdapter.java - adapt a SAX1 Parser to a SAX2 XMLReader.
// Written by David Megginson, sax@megginson.com
// NO WARRANTY!  This class is in the public domain.

// $Id: ParserAdapter.java,v 1.1 2001/03/05 21:40:06 jstrachan Exp $

package org.xml.sax.helpers;

import java.io.IOException;
import java.util.Enumeration;

import org.xml.sax.Parser;      // deprecated
import org.xml.sax.InputSource;
import org.xml.sax.Locator;
import org.xml.sax.AttributeList; // deprecated
import org.xml.sax.EntityResolver;
import org.xml.sax.DTDHandler;
import org.xml.sax.DocumentHandler; // deprecated
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;

import org.xml.sax.XMLReader;
import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;


/**
 * Adapt a SAX1 Parser as a SAX2 XMLReader.
 *
 * <blockquote>
 * <em>This module, both source code and documentation, is in the
 * Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
 * </blockquote>
 *
 * <p>This class wraps a SAX1 {@link org.xml.sax.Parser Parser}
 * and makes it act as a SAX2 {@link org.xml.sax.XMLReader XMLReader},
 * with feature, property, and Namespace support.  Note
 * that it is not possible to report {@link org.xml.sax.ContentHandler#skippedEntity
 * skippedEntity} events, since SAX1 does not make that information available.</p>
 *
 * <p>This adapter does not test for duplicate Namespace-qualified
 * attribute names.</p>
 *
 * @since SAX 2.0
 * @author David Megginson, 
 *         <a href="mailto:sax@megginson.com">sax@megginson.com</a>
 * @version 2.0
 * @see org.xml.sax.helpers.XMLReaderAdapter
 * @see org.xml.sax.XMLReader
 * @see org.xml.sax.Parser
 */
public class ParserAdapter implements XMLReader, DocumentHandler
{


    ////////////////////////////////////////////////////////////////////
    // Constructors.
    ////////////////////////////////////////////////////////////////////


    /**
     * Construct a new parser adapter.
     *
     * <p>Use the "org.xml.sax.parser" property to locate the
     * embedded SAX1 driver.</p>
     *
     * @exception org.xml.sax.SAXException If the embedded driver
     *            cannot be instantiated or if the
     *            org.xml.sax.parser property is not specified.
     */
    public ParserAdapter ()
      throws SAXException
    {
        super();

        String driver = System.getProperty("org.xml.sax.parser");

        try {
            setup(ParserFactory.makeParser());
        } catch (ClassNotFoundException e1) {
            throw new
                SAXException("Cannot find SAX1 driver class " +
                             driver, e1);
        } catch (IllegalAccessException e2) {
            throw new
                SAXException("SAX1 driver class " +
                             driver +
                             " found but cannot be loaded", e2);
        } catch (InstantiationException e3) {
            throw new
                SAXException("SAX1 driver class " +
                             driver +
                             " loaded but cannot be instantiated", e3);
        } catch (ClassCastException e4) {
            throw new
                SAXException("SAX1 driver class " +
                             driver +
                             " does not implement org.xml.sax.Parser");
        } catch (NullPointerException e5) {
            throw new 
                SAXException("System property org.xml.sax.parser not specified");
        }
    }


    /**
     * Construct a new parser adapter.
     *
     * <p>Note that the embedded parser cannot be changed once the
     * adapter is created; to embed a different parser, allocate
     * a new ParserAdapter.</p>
     *
     * @param parser The SAX1 parser to embed.
     * @exception java.lang.NullPointerException If the parser parameter
     *            is null.
     */
    public ParserAdapter (Parser parser)
    {
        super();
        setup(parser);
    }


    /**
     * Internal setup method.
     *
     * @param parser The embedded parser.
     * @exception java.lang.NullPointerException If the parser parameter
     *            is null.
     */
    private void setup (Parser parser)
    {
        if (parser == null) {
            throw new
                NullPointerException("Parser argument must not be null");
        }
        this.parser = parser;
        atts = new AttributesImpl();
        nsSupport = new NamespaceSupport();
        attAdapter = new AttributeListAdapter();
    }



    ////////////////////////////////////////////////////////////////////
    // Implementation of org.xml.sax.XMLReader.
    ////////////////////////////////////////////////////////////////////


    //
    // Internal constants for the sake of convenience.
    //
    private final static String FEATURES = "http://xml.org/sax/features/";
    private final static String NAMESPACES = FEATURES + "namespaces";
    private final static String NAMESPACE_PREFIXES = FEATURES + "namespace-prefixes";
    private final static String VALIDATION = FEATURES + "validation";
    private final static String EXTERNAL_GENERAL =
        FEATURES + "external-general-entities";
    private final static String EXTERNAL_PARAMETER =
        FEATURES + "external-parameter-entities";


    /**
     * Set a feature for the parser.
     *
     * <p>The only features supported are namespaces and 
     * namespace-prefixes.</p>
     *
     * @param name The feature name, as a complete URI.
     * @param state The requested feature state.
     * @exception org.xml.sax.SAXNotRecognizedException If the feature
     *            name is not known.
     * @exception org.xml.sax.SAXNotSupportedException If the feature
     *            state is not supported.
     * @see org.xml.sax.XMLReader#setFeature
     */
    public void setFeature (String name, boolean state)
        throws SAXNotRecognizedException, SAXNotSupportedException
    {
        if (name.equals(NAMESPACES)) {
            checkNotParsing("feature", name);
            namespaces = state;
            if (!namespaces && !prefixes) {
                prefixes = true;
            }
        } else if (name.equals(NAMESPACE_PREFIXES)) {
            checkNotParsing("feature", name);
            prefixes = state;
            if (!prefixes && !namespaces) {
                namespaces = true;
            }
        } else if (name.equals(VALIDATION) ||
                   name.equals(EXTERNAL_GENERAL) ||
                   name.equals(EXTERNAL_PARAMETER)) {
            throw new SAXNotSupportedException("Feature: " + name);
        } else {
            throw new SAXNotRecognizedException("Feature: " + name);
        }
    }


    /**
     * Check a parser feature.
     *
     * <p>The only features supported are namespaces and 
     * namespace-prefixes.</p>
     *
     * @param name The feature name, as a complete URI.
     * @return The current feature state.
     * @exception org.xml.sax.SAXNotRecognizedException If the feature
     *            name is not known.
     * @exception org.xml.sax.SAXNotSupportedException If querying the
     *            feature state is not supported.
     * @see org.xml.sax.XMLReader#setFeature
     */
    public boolean getFeature (String name)
        throws SAXNotRecognizedException, SAXNotSupportedException
    {
        if (name.equals(NAMESPACES)) {
            return namespaces;
        } else if (name.equals(NAMESPACE_PREFIXES)) {
            return prefixes;
        } else if (name.equals(VALIDATION) ||
                   name.equals(EXTERNAL_GENERAL) ||
                   name.equals(EXTERNAL_PARAMETER)) {
            throw new SAXNotSupportedException("Feature: " + name);
        } else {
            throw new SAXNotRecognizedException("Feature: " + name);
        }
    }


    /**
     * Set a parser property.
     *
     * <p>No special properties are currently supported.</p>
     *
     * @param name The property name.
     * @param value The property value.
     * @exception org.xml.sax.SAXNotRecognizedException If the feature
     *            name is not known.
     * @exception org.xml.sax.SAXNotSupportedException If the feature
     *            state is not supported.
     * @see org.xml.sax.XMLReader#setProperty
     */
    public void setProperty (String name, Object value)
        throws SAXNotRecognizedException, SAXNotSupportedException
    {
        throw new SAXNotRecognizedException("Property: " + name);
    }


    /**
     * Get a parser property.
     *
     * <p>No special properties are currently supported.</p>
     *
     * @param name The property name.
     * @return The property value.
     * @exception org.xml.sax.SAXNotRecognizedException If the feature
     *            name is not known.
     * @exception org.xml.sax.SAXNotSupportedException If the feature
     *            state is not supported.
     * @see org.xml.sax.XMLReader#getProperty
     */
    public Object getProperty (String name)
        throws SAXNotRecognizedException, SAXNotSupportedException
    {
        throw new SAXNotRecognizedException("Property: " + name);
    }


    /**
     * Set the entity resolver.
     *
     * @param resolver The new entity resolver.
     * @exception java.lang.NullPointerException If the entity resolver
     *            parameter is null.
     * @see org.xml.sax.XMLReader#setEntityResolver
     */
    public void setEntityResolver (EntityResolver resolver)
    {
        if (resolver == null) {
            throw new NullPointerException("Null entity resolver");
        }
        entityResolver = resolver;
    }


    /**
     * Return the current entity resolver.
     *
     * @return The current entity resolver, or null if none was supplied.
     * @see org.xml.sax.XMLReader#getEntityResolver
     */
    public EntityResolver getEntityResolver ()
    {
        return entityResolver;
    }


    /**
     * Set the DTD handler.
     *
     * @param resolver The new DTD handler.
     * @exception java.lang.NullPointerException If the DTD handler
     *            parameter is null.
     * @see org.xml.sax.XMLReader#setEntityResolver
     */
    public void setDTDHandler (DTDHandler handler)
    {
        if (handler == null) {
            throw new NullPointerException("Null DTD handler");
        }
        dtdHandler = handler;
    }


    /**
     * Return the current DTD handler.
     *
     * @return The current DTD handler, or null if none was supplied.
     * @see org.xml.sax.XMLReader#getEntityResolver
     */
    public DTDHandler getDTDHandler ()
    {
        return dtdHandler;
    }


    /**
     * Set the content handler.
     *
     * @param resolver The new content handler.
     * @exception java.lang.NullPointerException If the content handler
     *            parameter is null.
     * @see org.xml.sax.XMLReader#setEntityResolver
     */
    public void setContentHandler (ContentHandler handler)
    {
        if (handler == null) {
            throw new NullPointerException("Null content handler");
        }
        contentHandler = handler;
    }


    /**
     * Return the current content handler.
     *
     * @return The current content handler, or null if none was supplied.
     * @see org.xml.sax.XMLReader#getEntityResolver
     */
    public ContentHandler getContentHandler ()
    {
        return contentHandler;
    }


    /**
     * Set the error handler.
     *
     * @param resolver The new error handler.
     * @exception java.lang.NullPointerException If the error handler
     *            parameter is null.
     * @see org.xml.sax.XMLReader#setEntityResolver
     */
    public void setErrorHandler (ErrorHandler handler)
    {
        if (handler == null) {
            throw new NullPointerException("Null error handler");
        }
        errorHandler = handler;
    }


    /**
     * Return the current error handler.
     *
     * @return The current error handler, or null if none was supplied.
     * @see org.xml.sax.XMLReader#getEntityResolver
     */
    public ErrorHandler getErrorHandler ()
    {
        return errorHandler;
    }


    /**
     * Parse an XML document.
     *
     * @param systemId The absolute URL of the document.
     * @exception java.io.IOException If there is a problem reading
     *            the raw content of the document.
     * @exception org.xml.sax.SAXException If there is a problem
     *            processing the document.
     * @see #parse(org.xml.sax.InputSource)
     * @see org.xml.sax.Parser#parse(java.lang.String)
     */
    public void parse (String systemId)
        throws IOException, SAXException
    {
        parse(new InputSource(systemId));
    }


    /**
     * Parse an XML document.
     *
     * @param input An input source for the document.
     * @exception java.io.IOException If there is a problem reading
     *            the raw content of the document.
     * @exception org.xml.sax.SAXException If there is a problem
     *            processing the document.
     * @see #parse(java.lang.String)
     * @see org.xml.sax.Parser#parse(org.xml.sax.InputSource)
     */
    public void parse (InputSource input)
        throws IOException, SAXException
    {
        if (parsing) {
            throw new SAXException("Parser is already in use");
        }
        setupParser();
        parsing = true;
        try {
            parser.parse(input);
        } finally {
            parsing = false;
        }
        parsing = false;
    }



    ////////////////////////////////////////////////////////////////////
    // Implementation of org.xml.sax.DocumentHandler.
    ////////////////////////////////////////////////////////////////////


    /**
     * Adapt a SAX1 document locator event.
     *
     * @param locator A document locator.
     * @see org.xml.sax.ContentHandler#setDocumentLocator
     */
    public void setDocumentLocator (Locator locator)
    {
        this.locator = locator;
        if (contentHandler != null) {
            contentHandler.setDocumentLocator(locator);
        }
    }


    /**
     * Adapt a SAX1 start document event.
     *
     * @exception org.xml.sax.SAXException The client may raise a
     *            processing exception.
     * @see org.xml.sax.DocumentHandler#startDocument
     */
    public void startDocument ()
        throws SAXException
    {
        if (contentHandler != null) {
            contentHandler.startDocument();
        }
    }


    /**
     * Adapt a SAX1 end document event.
     *
     * @exception org.xml.sax.SAXException The client may raise a
     *            processing exception.
     * @see org.xml.sax.DocumentHandler#endDocument
     */
    public void endDocument ()
        throws SAXException
    {
        if (contentHandler != null) {
            contentHandler.endDocument();
        }
    }


    /**
     * Adapt a SAX1 startElement event.
     *
     * <p>If necessary, perform Namespace processing.</p>
     *
     * @param qName The qualified (prefixed) name.
     * @param qAtts The XML 1.0 attribute list (with qnames).
     */
    public void startElement (String qName, AttributeList qAtts)
        throws SAXException
    {
                                // If we're not doing Namespace
                                // processing, dispatch this quickly.
        if (!namespaces) {
            if (contentHandler != null) {
                attAdapter.setAttributeList(qAtts);
                contentHandler.startElement("", "", qName.intern(),
                                            attAdapter);
            }
            return;
        }


                                // OK, we're doing Namespace processing.
        nsSupport.pushContext();
        boolean seenDecl = false;
        atts.clear();
        
                                // Take a first pass and copy all
                                // attributes into the SAX2 attribute
                                // list, noting any Namespace 
                                // declarations.
        int length = qAtts.getLength();
        for (int i = 0; i < length; i++) {
            String attQName = qAtts.getName(i);
            String type = qAtts.getType(i);
            String value = qAtts.getValue(i);

                                // Found a declaration...
            if (attQName.startsWith("xmlns")) {
                String prefix;
                int n = attQName.indexOf(':');
                if (n == -1) {
                    prefix = "";
                } else {
                    prefix = attQName.substring(n+1);
                }
                if (!nsSupport.declarePrefix(prefix, value)) {
                    reportError("Illegal Namespace prefix: " + prefix);
                }
                if (contentHandler != null) {
                    contentHandler.startPrefixMapping(prefix, value);
                }
                                // We may still have to add this to
                                // the list.
                if (prefixes) {
                    atts.addAttribute("", "", attQName.intern(),
                                      type, value);
                }
                seenDecl = true;

                                // This isn't a declaration.
            } else {
                String attName[] = processName(attQName, true);
                atts.addAttribute(attName[0], attName[1], attName[2],
                                  type, value);
            }
        }
        
                                // If there was a Namespace declaration,
                                // we have to make a second pass just
                                // to be safe -- this will happen very
                                // rarely, possibly only once for each
                                // document.
        if (seenDecl) {
            length = atts.getLength();
            for (int i = 0; i < length; i++) {
                String attQName = atts.getQName(i);
                if (!attQName.startsWith("xmlns")) {
                    String attName[] = processName(attQName, true);
                    atts.setURI(i, attName[0]);
                    atts.setLocalName(i, attName[1]);
                }
            }
        }

                                // OK, finally report the event.
        if (contentHandler != null) {
            String name[] = processName(qName, false);
            contentHandler.startElement(name[0], name[1], name[2], atts);
        }
    }


    /**
     * Adapt a SAX1 end element event.
     *
     * @param qName The qualified (prefixed) name.
     * @exception org.xml.sax.SAXException The client may raise a
     *            processing exception.
     * @see org.xml.sax.DocumentHandler#endElement
     */
    public void endElement (String qName)
        throws SAXException
    {
                                // If we're not doing Namespace
                                // processing, dispatch this quickly.
        if (!namespaces) {
            if (contentHandler != null) {
                contentHandler.endElement("", "", qName.intern());
            }
            return;
        }

                                // Split the name.
        String names[] = processName(qName, false);
        if (contentHandler != null) {
            contentHandler.endElement(names[0], names[1], names[2]);
            Enumeration prefixes = nsSupport.getDeclaredPrefixes();
            while (prefixes.hasMoreElements()) {
                String prefix = (String)prefixes.nextElement();
                contentHandler.endPrefixMapping(prefix);
            }
        }
        nsSupport.popContext();
    }


    /**
     * Adapt a SAX1 characters event.
     *
     * @param ch An array of characters.
     * @param start The starting position in the array.
     * @param length The number of characters to use.
     * @exception org.xml.sax.SAXException The client may raise a
     *            processing exception.
     * @see org.xml.sax.DocumentHandler#characters
     */
    public void characters (char ch[], int start, int length)
        throws SAXException
    {
        if (contentHandler != null) {
            contentHandler.characters(ch, start, length);
        }
    }


    /**
     * Adapt a SAX1 ignorable whitespace event.
     *
     * @param ch An array of characters.
     * @param start The starting position in the array.
     * @param length The number of characters to use.
     * @exception org.xml.sax.SAXException The client may raise a
     *            processing exception.
     * @see org.xml.sax.DocumentHandler#ignorableWhitespace
     */
    public void ignorableWhitespace (char ch[], int start, int length)
        throws SAXException
    {
        if (contentHandler != null) {
            contentHandler.ignorableWhitespace(ch, start, length);
        }
    }


    /**
     * Adapt a SAX1 processing instruction event.
     *
     * @param target The processing instruction target.
     * @param data The remainder of the processing instruction
     * @exception org.xml.sax.SAXException The client may raise a
     *            processing exception.
     * @see org.xml.sax.DocumentHandler#processingInstruction
     */
    public void processingInstruction (String target, String data)
        throws SAXException
    {
        if (contentHandler != null) {
            contentHandler.processingInstruction(target, data);
        }
    }



    ////////////////////////////////////////////////////////////////////
    // Internal utility methods.
    ////////////////////////////////////////////////////////////////////


    /**
     * Initialize the parser before each run.
     */
    private void setupParser ()
    {
        nsSupport.reset();

        if (entityResolver != null) {
            parser.setEntityResolver(entityResolver);
        }
        if (dtdHandler != null) {
            parser.setDTDHandler(dtdHandler);
        }
        if (errorHandler != null) {
            parser.setErrorHandler(errorHandler);
        }
        parser.setDocumentHandler(this);
        locator = null;
    }


    /**
     * Process a qualified (prefixed) name.
     *
     * <p>If the name has an undeclared prefix, use only the qname
     * and make an ErrorHandler.error callback in case the app is
     * interested.</p>
     *
     * @param qName The qualified (prefixed) name.
     * @param isAttribute true if this is an attribute name.
     * @return The name split into three parts.
     * @exception org.xml.sax.SAXException The client may throw
     *            an exception if there is an error callback.
     */
    private String [] processName (String qName, boolean isAttribute)
        throws SAXException
    {
        String parts[] = nsSupport.processName(qName, nameParts,
                                               isAttribute);
        if (parts == null) {
            parts = new String[3];
            parts[2] = qName.intern();
            reportError("Undeclared prefix: " + qName);
        }
        return parts;
    }


    /**
     * Report a non-fatal error.
     *
     * @param message The error message.
     * @exception org.xml.sax.SAXException The client may throw
     *            an exception.
     */
    void reportError (String message)
        throws SAXException
    {
        if (errorHandler == null) {
            return;
        }

        SAXParseException e;
        if (locator != null) {
            e = new SAXParseException(message, locator);
        } else {
            e = new SAXParseException(message, null, null, -1, -1);
        }
        errorHandler.error(e);
    }


    /**
     * Throw an exception if we are parsing.
     *
     * <p>Use this method to detect illegal feature or
     * property changes.</p>
     *
     * @param type The type of thing (feature or property).
     * @param name The feature or property name.
     * @exception org.xml.sax.SAXNotSupportedException If a
     *            document is currently being parsed.
     */
    private void checkNotParsing (String type, String name)
        throws SAXNotSupportedException
    {
        if (parsing) {
            throw new SAXNotSupportedException("Cannot change " +
                                               type + ' ' +
                                               name + " while parsing");
                                               
        }
    }



    ////////////////////////////////////////////////////////////////////
    // Internal state.
    ////////////////////////////////////////////////////////////////////

    private NamespaceSupport nsSupport;
    private AttributeListAdapter attAdapter;

    private boolean parsing = false;
    private String nameParts[] = new String[3];

    private Parser parser = null;

    private AttributesImpl atts = null;

                                // Features
    private boolean namespaces = true;
    private boolean prefixes = false;

                                // Properties

                                // Handlers
    Locator locator;

    EntityResolver entityResolver = null;
    DTDHandler dtdHandler = null;
    ContentHandler contentHandler = null;
    ErrorHandler errorHandler = null;



    ////////////////////////////////////////////////////////////////////
    // Inner class to wrap an AttributeList when not doing NS proc.
    ////////////////////////////////////////////////////////////////////


    /**
     * Adapt a SAX1 AttributeList as a SAX2 Attributes object.
     *
     * <p>This class is in the Public Domain, and comes with NO
     * WARRANTY of any kind.</p>
     *
     * <p>This wrapper class is used only when Namespace support
     * is disabled -- it provides pretty much a direct mapping
     * from SAX1 to SAX2, except that names and types are 
     * interned whenever requested.</p>
     */
    final class AttributeListAdapter implements Attributes
    {

        /**
         * Construct a new adapter.
         */
        AttributeListAdapter ()
        {
        }


        /**
         * Set the embedded AttributeList.
         *
         * <p>This method must be invoked before any of the others
         * can be used.</p>
         *
         * @param The SAX1 attribute list (with qnames).
         */
        void setAttributeList (AttributeList qAtts)
        {
            this.qAtts = qAtts;
        }


        /**
         * Return the length of the attribute list.
         *
         * @return The number of attributes in the list.
         * @see org.xml.sax.Attributes#getLength
         */
        public int getLength ()
        {
            return qAtts.getLength();
        }


        /**
         * Return the Namespace URI of the specified attribute.
         *
         * @param The attribute's index.
         * @return Always the empty string.
         * @see org.xml.sax.Attributes#getURI
         */
        public String getURI (int i)
        {
            return "";
        }


        /**
         * Return the local name of the specified attribute.
         *
         * @param The attribute's index.
         * @return Always the empty string.
         * @see org.xml.sax.Attributes#getLocalName
         */
        public String getLocalName (int i)
        {
            return "";
        }


        /**
         * Return the qualified (prefixed) name of the specified attribute.
         *
         * @param The attribute's index.
         * @return The attribute's qualified name, internalized.
         */
        public String getQName (int i)
        {
            return qAtts.getName(i).intern();
        }


        /**
         * Return the type of the specified attribute.
         *
         * @param The attribute's index.
         * @return The attribute's type as an internalized string.
         */
        public String getType (int i)
        {
            return qAtts.getType(i).intern();
        }


        /**
         * Return the value of the specified attribute.
         *
         * @param The attribute's index.
         * @return The attribute's value.
         */
        public String getValue (int i)
        {
            return qAtts.getValue(i);
        }


        /**
         * Look up an attribute index by Namespace name.
         *
         * @param uri The Namespace URI or the empty string.
         * @param localName The local name.
         * @return The attributes index, or -1 if none was found.
         * @see org.xml.sax.Attributes#getIndex(java.lang.String,java.lang.String)
         */
        public int getIndex (String uri, String localName)
        {
            return -1;
        }


        /**
         * Look up an attribute index by qualified (prefixed) name.
         *
         * @param qName The qualified name.
         * @return The attributes index, or -1 if none was found.
         * @see org.xml.sax.Attributes#getIndex(java.lang.String)
         */
        public int getIndex (String qName)
        {
            int max = atts.getLength();
            for (int i = 0; i < max; i++) {
                if (qAtts.getName(i).equals(qName)) {
                    return i;
                }
            }
            return -1;
        }


        /**
         * Look up the type of an attribute by Namespace name.
         *
         * @param uri The Namespace URI
         * @param localName The local name.
         * @return The attribute's type as an internalized string.
         */
        public String getType (String uri, String localName)
        {
            return null;
        }


        /**
         * Look up the type of an attribute by qualified (prefixed) name.
         *
         * @param qName The qualified name.
         * @return The attribute's type as an internalized string.
         */
        public String getType (String qName)
        {
            return qAtts.getType(qName).intern();
        }


        /**
         * Look up the value of an attribute by Namespace name.
         *
         * @param uri The Namespace URI
         * @param localName The local name.
         * @return The attribute's value.
         */
        public String getValue (String uri, String localName)
        {
            return null;
        }


        /**
         * Look up the value of an attribute by qualified (prefixed) name.
         *
         * @param qName The qualified name.
         * @return The attribute's value.
         */
        public String getValue (String qName)
        {
            return qAtts.getValue(qName);
        }

        private AttributeList qAtts;
    }
}

// end of ParserAdapter.java