/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.xerces.impl.xs;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.Hashtable;
import java.util.Locale;
import java.util.StringTokenizer;
import java.util.WeakHashMap;

import org.apache.xerces.dom.DOMErrorImpl;
import org.apache.xerces.dom.DOMMessageFormatter;
import org.apache.xerces.dom.DOMStringListImpl;
import org.apache.xerces.impl.Constants;
import org.apache.xerces.impl.XMLEntityManager;
import org.apache.xerces.impl.XMLErrorReporter;
import org.apache.xerces.impl.dv.InvalidDatatypeValueException;
import org.apache.xerces.impl.dv.SchemaDVFactory;
import org.apache.xerces.impl.dv.xs.SchemaDVFactoryImpl;
import org.apache.xerces.impl.xs.models.CMBuilder;
import org.apache.xerces.impl.xs.models.CMNodeFactory;
import org.apache.xerces.impl.xs.traversers.XSDHandler;
import org.apache.xerces.util.DOMEntityResolverWrapper;
import org.apache.xerces.util.DOMErrorHandlerWrapper;
import org.apache.xerces.util.DefaultErrorHandler;
import org.apache.xerces.util.MessageFormatter;
import org.apache.xerces.util.ParserConfigurationSettings;
import org.apache.xerces.util.SymbolTable;
import org.apache.xerces.util.XMLSymbols;
import org.apache.xerces.util.URI.MalformedURIException;
import org.apache.xerces.xni.QName;
import org.apache.xerces.xni.XNIException;
import org.apache.xerces.xni.grammars.Grammar;
import org.apache.xerces.xni.grammars.XMLGrammarDescription;
import org.apache.xerces.xni.grammars.XMLGrammarLoader;
import org.apache.xerces.xni.grammars.XMLGrammarPool;
import org.apache.xerces.xni.grammars.XSGrammar;
import org.apache.xerces.xni.parser.XMLComponent;
import org.apache.xerces.xni.parser.XMLComponentManager;
import org.apache.xerces.xni.parser.XMLConfigurationException;
import org.apache.xerces.xni.parser.XMLEntityResolver;
import org.apache.xerces.xni.parser.XMLErrorHandler;
import org.apache.xerces.xni.parser.XMLInputSource;
import org.apache.xerces.xs.LSInputList;
import org.apache.xerces.xs.StringList;
import org.apache.xerces.xs.XSLoader;
import org.apache.xerces.xs.XSModel;
import org.w3c.dom.DOMConfiguration;
import org.w3c.dom.DOMError;
import org.w3c.dom.DOMErrorHandler;
import org.w3c.dom.DOMException;
import org.w3c.dom.DOMStringList;
import org.w3c.dom.ls.LSInput;
import org.w3c.dom.ls.LSResourceResolver;
import org.xml.sax.InputSource;

This class implements xni.grammars.XMLGrammarLoader.
It also serves as implementation of xs.XSLoader interface and DOMConfiguration interface.
This class is designed to interact either with a proxy for a user application 
which wants to preparse schemas, or with our own Schema validator.  
It is hoped that none of these "external" classes will therefore need to communicate directly
with XSDHandler in future.
This class only knows how to make XSDHandler do its thing.
The caller must ensure that all its properties (schemaLocation, JAXPSchemaSource
etc.) have been properly set.
Author:
Neil Graham, IBM
@xerces.internal
Version:
$Id: XMLSchemaLoader.java 982466 2010-08-05 04:41:01Z mrglavas $/**
 * This class implements xni.grammars.XMLGrammarLoader.
 * It also serves as implementation of xs.XSLoader interface and DOMConfiguration interface.
 * 
 * This class is designed to interact either with a proxy for a user application 
 * which wants to preparse schemas, or with our own Schema validator.  
 * It is hoped that none of these "external" classes will therefore need to communicate directly
 * with XSDHandler in future.
 * <p>This class only knows how to make XSDHandler do its thing.
 * The caller must ensure that all its properties (schemaLocation, JAXPSchemaSource
 * etc.) have been properly set.
 *
 * @xerces.internal 
 *
 * @author Neil Graham, IBM
 * @version $Id: XMLSchemaLoader.java 982466 2010-08-05 04:41:01Z mrglavas $
 */
public class XMLSchemaLoader implements XMLGrammarLoader, XMLComponent, XSElementDeclHelper,
// XML Component API 
XSLoader, DOMConfiguration {
    
    // Feature identifiers:
    
    
Feature identifier: schema full checking/** Feature identifier: schema full checking*/
    protected static final String SCHEMA_FULL_CHECKING =
        Constants.XERCES_FEATURE_PREFIX + Constants.SCHEMA_FULL_CHECKING;
    
    
Feature identifier: continue after fatal error. /** Feature identifier: continue after fatal error. */
    protected static final String CONTINUE_AFTER_FATAL_ERROR =
        Constants.XERCES_FEATURE_PREFIX + Constants.CONTINUE_AFTER_FATAL_ERROR_FEATURE;
    
    
Feature identifier: allow java encodings to be recognized when parsing schema docs. /** Feature identifier: allow java encodings to be recognized when parsing schema docs. */
    protected static final String ALLOW_JAVA_ENCODINGS =
        Constants.XERCES_FEATURE_PREFIX + Constants.ALLOW_JAVA_ENCODINGS_FEATURE;
    
    
Feature identifier: standard uri conformant feature. /** Feature identifier: standard uri conformant feature. */
    protected static final String STANDARD_URI_CONFORMANT_FEATURE =
        Constants.XERCES_FEATURE_PREFIX + Constants.STANDARD_URI_CONFORMANT_FEATURE;
    
    
Feature identifier: validate annotations. /** Feature identifier: validate annotations. */
    protected static final String VALIDATE_ANNOTATIONS =
        Constants.XERCES_FEATURE_PREFIX + Constants.VALIDATE_ANNOTATIONS_FEATURE;
        
    
Feature: disallow doctype/** Feature: disallow doctype*/
    protected static final String DISALLOW_DOCTYPE = 
        Constants.XERCES_FEATURE_PREFIX + Constants.DISALLOW_DOCTYPE_DECL_FEATURE;
    
    
Feature: generate synthetic annotations /** Feature: generate synthetic annotations */
    protected static final String GENERATE_SYNTHETIC_ANNOTATIONS = 
        Constants.XERCES_FEATURE_PREFIX + Constants.GENERATE_SYNTHETIC_ANNOTATIONS_FEATURE;
    
    
Feature identifier: honour all schemaLocations /** Feature identifier: honour all schemaLocations */
    protected static final String HONOUR_ALL_SCHEMALOCATIONS = 
        Constants.XERCES_FEATURE_PREFIX + Constants.HONOUR_ALL_SCHEMALOCATIONS_FEATURE;
    
    protected static final String AUGMENT_PSVI = 
        Constants.XERCES_FEATURE_PREFIX + Constants.SCHEMA_AUGMENT_PSVI;
    
    protected static final String PARSER_SETTINGS = 
        Constants.XERCES_FEATURE_PREFIX + Constants.PARSER_SETTINGS;
    
    
Feature identifier: namespace growth /** Feature identifier: namespace growth */
    protected static final String NAMESPACE_GROWTH = 
        Constants.XERCES_FEATURE_PREFIX + Constants.NAMESPACE_GROWTH_FEATURE;
    
    
Feature identifier: tolerate duplicates /** Feature identifier: tolerate duplicates */
    protected static final String TOLERATE_DUPLICATES = 
        Constants.XERCES_FEATURE_PREFIX + Constants.TOLERATE_DUPLICATES_FEATURE;
    
    
Property identifier: Schema DV Factory /** Property identifier: Schema DV Factory */
    protected static final String SCHEMA_DV_FACTORY = 
        Constants.XERCES_PROPERTY_PREFIX + Constants.SCHEMA_DV_FACTORY_PROPERTY;
    
    // recognized features:
    private static final String[] RECOGNIZED_FEATURES = {
        SCHEMA_FULL_CHECKING,
        AUGMENT_PSVI,
        CONTINUE_AFTER_FATAL_ERROR,
        ALLOW_JAVA_ENCODINGS,
        STANDARD_URI_CONFORMANT_FEATURE, 
        DISALLOW_DOCTYPE,
        GENERATE_SYNTHETIC_ANNOTATIONS,
        VALIDATE_ANNOTATIONS,
        HONOUR_ALL_SCHEMALOCATIONS,
        NAMESPACE_GROWTH,
        TOLERATE_DUPLICATES
    };
    
    // property identifiers
    
    
Property identifier: symbol table. /** Property identifier: symbol table. */
    public static final String SYMBOL_TABLE =
        Constants.XERCES_PROPERTY_PREFIX + Constants.SYMBOL_TABLE_PROPERTY;
    
    
Property identifier: error reporter. /** Property identifier: error reporter. */
    public static final String ERROR_REPORTER =
        Constants.XERCES_PROPERTY_PREFIX + Constants.ERROR_REPORTER_PROPERTY;
    
    
Property identifier: error handler. /** Property identifier: error handler. */
    protected static final String ERROR_HANDLER =
        Constants.XERCES_PROPERTY_PREFIX + Constants.ERROR_HANDLER_PROPERTY;
    
    
Property identifier: entity resolver. /** Property identifier: entity resolver. */
    public static final String ENTITY_RESOLVER =
        Constants.XERCES_PROPERTY_PREFIX + Constants.ENTITY_RESOLVER_PROPERTY;
    
    
Property identifier: grammar pool. /** Property identifier: grammar pool. */
    public static final String XMLGRAMMAR_POOL =
        Constants.XERCES_PROPERTY_PREFIX + Constants.XMLGRAMMAR_POOL_PROPERTY;
    
    
Property identifier: schema location. /** Property identifier: schema location. */
    protected static final String SCHEMA_LOCATION =
        Constants.XERCES_PROPERTY_PREFIX + Constants.SCHEMA_LOCATION;
    
    
Property identifier: no namespace schema location. /** Property identifier: no namespace schema location. */
    protected static final String SCHEMA_NONS_LOCATION =
        Constants.XERCES_PROPERTY_PREFIX + Constants.SCHEMA_NONS_LOCATION;
    
    
Property identifier: JAXP schema source. /** Property identifier: JAXP schema source. */
    protected static final String JAXP_SCHEMA_SOURCE =
        Constants.JAXP_PROPERTY_PREFIX + Constants.SCHEMA_SOURCE;
    
    protected static final String SECURITY_MANAGER =
        Constants.XERCES_PROPERTY_PREFIX + Constants.SECURITY_MANAGER_PROPERTY;
    
    
Property identifier: locale. /** Property identifier: locale. */
    protected static final String LOCALE =
        Constants.XERCES_PROPERTY_PREFIX + Constants.LOCALE_PROPERTY;
    
    protected static final String ENTITY_MANAGER =
        Constants.XERCES_PROPERTY_PREFIX + Constants.ENTITY_MANAGER_PROPERTY;   
    
    // recognized properties
    private static final String [] RECOGNIZED_PROPERTIES = {
        ENTITY_MANAGER,
        SYMBOL_TABLE,
        ERROR_REPORTER,
        ERROR_HANDLER,
        ENTITY_RESOLVER,
        XMLGRAMMAR_POOL,
        SCHEMA_LOCATION,
        SCHEMA_NONS_LOCATION,
        JAXP_SCHEMA_SOURCE,
        SECURITY_MANAGER,
        LOCALE,
        SCHEMA_DV_FACTORY
    };
    
    // Data
    
    // features and properties
    private final ParserConfigurationSettings fLoaderConfig = new ParserConfigurationSettings();
    private XMLErrorReporter fErrorReporter = new XMLErrorReporter ();
    private XMLEntityManager fEntityManager = null;
    private XMLEntityResolver fUserEntityResolver = null;
    private XMLGrammarPool fGrammarPool = null;
    private String fExternalSchemas = null;
    private String fExternalNoNSSchema = null;
    // JAXP property: schema source 
    private Object fJAXPSource = null;
    // is Schema Full Checking enabled
    private boolean fIsCheckedFully = false;
    // boolean that tells whether we've tested the JAXP property.
    private boolean fJAXPProcessed = false;
    // if features/properties has not been changed, the value of this attribute is "false"
    private boolean fSettingsChanged = true;
    
    // xml schema parsing
    private XSDHandler fSchemaHandler;
    private XSGrammarBucket fGrammarBucket;
    private XSDeclarationPool fDeclPool = null;
    private SubstitutionGroupHandler fSubGroupHandler;
    private CMBuilder fCMBuilder;
    private XSDDescription fXSDDescription = new XSDDescription();
    private SchemaDVFactory fDefaultSchemaDVFactory;
    
    private WeakHashMap fJAXPCache;
    private Locale fLocale = Locale.getDefault();
    
    // XSLoader attributes
    private DOMStringList fRecognizedParameters = null;
    
    
DOM L3 error handler /** DOM L3 error handler */
    private DOMErrorHandlerWrapper fErrorHandler = null;
    
    
DOM L3 resource resolver /** DOM L3 resource resolver */
    private DOMEntityResolverWrapper fResourceResolver = null;
    
    // default constructor.  Create objects we absolutely need:
    public XMLSchemaLoader() {
        this( new SymbolTable(), null, new XMLEntityManager(), null, null, null);
    }
    
    public XMLSchemaLoader(SymbolTable symbolTable) {
        this( symbolTable, null, new XMLEntityManager(), null, null, null);
    }
    
    
This constractor is used by the XMLSchemaValidator. Additional properties, i.e. XMLEntityManager, 
will be passed during reset(XMLComponentManager).
Params:
errorReporter – 
grammarBucket – 
sHandler – 
builder – /**
     * This constractor is used by the XMLSchemaValidator. Additional properties, i.e. XMLEntityManager, 
     * will be passed during reset(XMLComponentManager).
     * @param errorReporter
     * @param grammarBucket
     * @param sHandler
     * @param builder
     */
    XMLSchemaLoader(XMLErrorReporter errorReporter,
            XSGrammarBucket grammarBucket,
            SubstitutionGroupHandler sHandler, CMBuilder builder) {
        this(null, errorReporter, null, grammarBucket, sHandler, builder);
    }
    
    XMLSchemaLoader(SymbolTable symbolTable,
            XMLErrorReporter errorReporter,
            XMLEntityManager entityResolver,
            XSGrammarBucket grammarBucket,
            SubstitutionGroupHandler sHandler,
            CMBuilder builder) {
        
        // store properties and features in configuration
        fLoaderConfig.addRecognizedFeatures(RECOGNIZED_FEATURES);
        fLoaderConfig.addRecognizedProperties(RECOGNIZED_PROPERTIES); 
        if (symbolTable != null){ 
            fLoaderConfig.setProperty(SYMBOL_TABLE, symbolTable);       
        }
        
        if(errorReporter == null) {
            errorReporter = new XMLErrorReporter ();
            errorReporter.setLocale(fLocale);
            errorReporter.setProperty(ERROR_HANDLER, new DefaultErrorHandler());
            
        }
        fErrorReporter = errorReporter;
        // make sure error reporter knows about schemas...
        if(fErrorReporter.getMessageFormatter(XSMessageFormatter.SCHEMA_DOMAIN) == null) {
            fErrorReporter.putMessageFormatter(XSMessageFormatter.SCHEMA_DOMAIN, new XSMessageFormatter());
        }
        fLoaderConfig.setProperty(ERROR_REPORTER, fErrorReporter);
        fEntityManager = entityResolver;   
        // entity manager is null if XMLSchemaValidator creates the loader  
        if (fEntityManager != null){   
            fLoaderConfig.setProperty(ENTITY_MANAGER, fEntityManager);
        }
        
        // by default augment PSVI (i.e. don't use declaration pool)
        fLoaderConfig.setFeature(AUGMENT_PSVI, true);
        
        if(grammarBucket == null ) {
            grammarBucket = new XSGrammarBucket();
        }
        fGrammarBucket = grammarBucket;
        if (sHandler == null) {
            sHandler = new SubstitutionGroupHandler(this);
        }
        fSubGroupHandler = sHandler;
        
        //get an instance of the CMNodeFactory */
        CMNodeFactory nodeFactory = new CMNodeFactory() ;
        
        if(builder == null) {
            builder = new CMBuilder(nodeFactory);
        }
        fCMBuilder = builder;
        fSchemaHandler = new XSDHandler(fGrammarBucket);
        fJAXPCache = new WeakHashMap();
        
        fSettingsChanged = true;
    }
    
    
Returns a list of feature identifiers that are recognized by
this XMLGrammarLoader.  This method may return null if no features
are recognized.
/**
     * Returns a list of feature identifiers that are recognized by
     * this XMLGrammarLoader.  This method may return null if no features
     * are recognized.
     */
    public String[] getRecognizedFeatures() {
        return (String[])(RECOGNIZED_FEATURES.clone());
    } // getRecognizedFeatures():  String[]
    
    
Returns the state of a feature.
Params:
featureId – The feature identifier.
Throws:
XMLConfigurationException – Thrown on configuration error./**
     * Returns the state of a feature.
     *
     * @param featureId The feature identifier.
     *
     * @throws XMLConfigurationException Thrown on configuration error.
     */
    public boolean getFeature(String featureId)
    throws XMLConfigurationException {                
        return fLoaderConfig.getFeature(featureId);        
    } // getFeature (String):  boolean
    
    
Sets the state of a feature.
Params:
featureId – The feature identifier.
state –     The state of the feature.
Throws:
XMLConfigurationException – Thrown when a feature is not
                 recognized or cannot be set./**
     * Sets the state of a feature.
     *
     * @param featureId The feature identifier.
     * @param state     The state of the feature.
     *
     * @throws XMLConfigurationException Thrown when a feature is not
     *                  recognized or cannot be set.
     */
    public void setFeature(String featureId,
            boolean state) throws XMLConfigurationException {
        fSettingsChanged = true; 
        if(featureId.equals(CONTINUE_AFTER_FATAL_ERROR)) {
            fErrorReporter.setFeature(CONTINUE_AFTER_FATAL_ERROR, state);
        } 
        else if(featureId.equals(GENERATE_SYNTHETIC_ANNOTATIONS)) {
            fSchemaHandler.setGenerateSyntheticAnnotations(state);
        }
        fLoaderConfig.setFeature(featureId, state);
    } // setFeature(String, boolean)
    
    
Returns a list of property identifiers that are recognized by
this XMLGrammarLoader.  This method may return null if no properties
are recognized.
/**
     * Returns a list of property identifiers that are recognized by
     * this XMLGrammarLoader.  This method may return null if no properties
     * are recognized.
     */
    public String[] getRecognizedProperties() {
        return (String[])(RECOGNIZED_PROPERTIES.clone());
    } // getRecognizedProperties():  String[]
    
    
Returns the state of a property.
Params:
propertyId – The property identifier.
Throws:
XMLConfigurationException – Thrown on configuration error./**
     * Returns the state of a property.
     *
     * @param propertyId The property identifier.
     *
     * @throws XMLConfigurationException Thrown on configuration error.
     */
    public Object getProperty(String propertyId)
    throws XMLConfigurationException {
        return fLoaderConfig.getProperty(propertyId);
    } // getProperty(String):  Object
    
    
Sets the state of a property.
Params:
propertyId – The property identifier.
state –     The state of the property.
Throws:
XMLConfigurationException – Thrown when a property is not
                 recognized or cannot be set./**
     * Sets the state of a property.
     *
     * @param propertyId The property identifier.
     * @param state     The state of the property.
     *
     * @throws XMLConfigurationException Thrown when a property is not
     *                  recognized or cannot be set.
     */
    public void setProperty(String propertyId,
            Object state) throws XMLConfigurationException {                   
        fSettingsChanged = true;
        fLoaderConfig.setProperty(propertyId, state);    
        if (propertyId.equals(JAXP_SCHEMA_SOURCE)) {
            fJAXPSource = state;
            fJAXPProcessed = false;
        }  
        else if (propertyId.equals(XMLGRAMMAR_POOL)) {
            fGrammarPool = (XMLGrammarPool)state;
        } 
        else if (propertyId.equals(SCHEMA_LOCATION)) {
            fExternalSchemas = (String)state;
        }
        else if (propertyId.equals(SCHEMA_NONS_LOCATION)) {
            fExternalNoNSSchema = (String) state;
        }
        else if (propertyId.equals(LOCALE)) {
            setLocale((Locale) state);
        }
        else if (propertyId.equals(ENTITY_RESOLVER)) {
            fEntityManager.setProperty(ENTITY_RESOLVER, state);
        }
        else if (propertyId.equals(ERROR_REPORTER)) {
            fErrorReporter = (XMLErrorReporter)state;
            if (fErrorReporter.getMessageFormatter(XSMessageFormatter.SCHEMA_DOMAIN) == null) {
                fErrorReporter.putMessageFormatter(XSMessageFormatter.SCHEMA_DOMAIN, new XSMessageFormatter());
            }
        }
    } // setProperty(String, Object)
    
    
Set the locale to use for messages.
Params:
locale – The locale object to use for localization of messages.
Throws:
XNIException – Thrown if the parser does not support the
                        specified locale./**
     * Set the locale to use for messages.
     *
     * @param locale The locale object to use for localization of messages.
     *
     * @exception XNIException Thrown if the parser does not support the
     *                         specified locale.
     */
    public void setLocale(Locale locale) {
        fLocale = locale;
        fErrorReporter.setLocale(locale);
    } // setLocale(Locale)
    
    
Return the Locale the XMLGrammarLoader is using. /** Return the Locale the XMLGrammarLoader is using. */
    public Locale getLocale() {
        return fLocale;
    } // getLocale():  Locale
    
    
Sets the error handler.
Params:
errorHandler – The error handler./**
     * Sets the error handler.
     *
     * @param errorHandler The error handler.
     */
    public void setErrorHandler(XMLErrorHandler errorHandler) {
        fErrorReporter.setProperty(ERROR_HANDLER, errorHandler);
    } // setErrorHandler(XMLErrorHandler)
    
    
Returns the registered error handler.  /** Returns the registered error handler.  */
    public XMLErrorHandler getErrorHandler() {
        return fErrorReporter.getErrorHandler();
    } // getErrorHandler():  XMLErrorHandler
    
    
Sets the entity resolver.
Params:
entityResolver – The new entity resolver./**
     * Sets the entity resolver.
     *
     * @param entityResolver The new entity resolver.
     */
    public void setEntityResolver(XMLEntityResolver entityResolver) {
        fUserEntityResolver = entityResolver;
        fLoaderConfig.setProperty(ENTITY_RESOLVER, entityResolver);
        fEntityManager.setProperty(ENTITY_RESOLVER, entityResolver);
    } // setEntityResolver(XMLEntityResolver)
    
    
Returns the registered entity resolver.  /** Returns the registered entity resolver.  */
    public XMLEntityResolver getEntityResolver() {
        return fUserEntityResolver;
    } // getEntityResolver():  XMLEntityResolver
    
    
Returns a Grammar object by parsing the contents of the
entities pointed to by sources.
Params:
source – the locations of the entity which forms 
                     the staring point of the grammars to be constructed
Throws:
IOException –  when a problem is encounted reading the entity
XNIException – when a condition arises (such as a FatalError) that requires parsing
                         of the entity be terminated/**
     * Returns a Grammar object by parsing the contents of the
     * entities pointed to by sources.
     * 
     * @param source the locations of the entity which forms 
     *                      the staring point of the grammars to be constructed
     * @throws IOException  when a problem is encounted reading the entity
     * @throws XNIException when a condition arises (such as a FatalError) that requires parsing
     *                          of the entity be terminated
     */
    public void loadGrammar(XMLInputSource source[]) 
    throws IOException, XNIException {
        int numSource = source.length;
        for (int i = 0; i < numSource; ++i) {
            loadGrammar(source[i]);
        }   
    }
    
    
Returns a Grammar object by parsing the contents of the
entity pointed to by source.
Params:
source –        the location of the entity which forms
                         the starting point of the grammar to be constructed.
Throws:
IOException –      When a problem is encountered reading the entity
         XNIException    When a condition arises (such as a FatalError) that requires parsing
                             of the entity be terminated./**
     * Returns a Grammar object by parsing the contents of the
     * entity pointed to by source.
     *
     * @param source        the location of the entity which forms
     *                          the starting point of the grammar to be constructed.
     * @throws IOException      When a problem is encountered reading the entity
     *          XNIException    When a condition arises (such as a FatalError) that requires parsing
     *                              of the entity be terminated.
     */
    public Grammar loadGrammar(XMLInputSource source)
    throws IOException, XNIException {
        
        // REVISIT: this method should have a namespace parameter specified by 
        // user. In this case we can easily detect if a schema asked to be loaded
        // is already in the local cache.
        
        reset(fLoaderConfig);
        fSettingsChanged = false;
        XSDDescription desc = new XSDDescription();
        desc.fContextType = XSDDescription.CONTEXT_PREPARSE;
        desc.setBaseSystemId(source.getBaseSystemId());
        desc.setLiteralSystemId( source.getSystemId());
        // none of the other fields make sense for preparsing
        Hashtable locationPairs = new Hashtable();
        // Process external schema location properties.
        // We don't call tokenizeSchemaLocationStr here, because we also want
        // to check whether the values are valid URI.
        processExternalHints(fExternalSchemas, fExternalNoNSSchema,
                locationPairs, fErrorReporter);
        SchemaGrammar grammar = loadSchema(desc, source, locationPairs);
        
        if(grammar != null && fGrammarPool != null) {
            fGrammarPool.cacheGrammars(XMLGrammarDescription.XML_SCHEMA, fGrammarBucket.getGrammars());
            // NOTE: we only need to verify full checking in case the schema was not provided via JAXP
            // since full checking already verified for all JAXP schemas
            if(fIsCheckedFully && fJAXPCache.get(grammar) != grammar) {
                XSConstraints.fullSchemaChecking(fGrammarBucket, fSubGroupHandler, fCMBuilder, fErrorReporter);
            }
        }
        return grammar;
    } // loadGrammar(XMLInputSource):  Grammar
    
    
This method is called either from XMLGrammarLoader.loadGrammar or from XMLSchemaValidator.
Note: in either case, the EntityManager (or EntityResolvers) are not going to be invoked
to resolve the location of the schema in XSDDescription 
Params:
desc – 
source – 
locationPairs – 
Throws:
IOException – 
XNIException – 
Returns:
An XML Schema grammar/**
     * This method is called either from XMLGrammarLoader.loadGrammar or from XMLSchemaValidator.
     * Note: in either case, the EntityManager (or EntityResolvers) are not going to be invoked
     * to resolve the location of the schema in XSDDescription 
     * @param desc
     * @param source
     * @param locationPairs
     * @return An XML Schema grammar
     * @throws IOException
     * @throws XNIException
     */
    SchemaGrammar loadSchema(XSDDescription desc,
            XMLInputSource source,
            Hashtable locationPairs) throws IOException, XNIException {
        
        // this should only be done once per invocation of this object;
        // unless application alters JAXPSource in the mean time.
        if(!fJAXPProcessed) {
            processJAXPSchemaSource(locationPairs);
        }
        SchemaGrammar grammar = fSchemaHandler.parseSchema(source, desc, locationPairs);
        
        return grammar;
    } // loadSchema(XSDDescription, XMLInputSource):  SchemaGrammar
    
    
This method tries to resolve location of the given schema.
The loader stores the namespace/location pairs in a hashtable (use "" as the
namespace of absent namespace). When resolving an entity, loader first tries
to find in the hashtable whether there is a value for that namespace,
if so, pass that location value to the user-defined entity resolver.
Params:
desc – 
locationPairs – 
entityResolver – 
Throws:
IOException – 
Returns:
the XMLInputSource/** 
     * This method tries to resolve location of the given schema.
     * The loader stores the namespace/location pairs in a hashtable (use "" as the
     * namespace of absent namespace). When resolving an entity, loader first tries
     * to find in the hashtable whether there is a value for that namespace,
     * if so, pass that location value to the user-defined entity resolver.
     *
     * @param desc
     * @param locationPairs
     * @param entityResolver
     * @return the XMLInputSource
     * @throws IOException
     */
    public static XMLInputSource resolveDocument(XSDDescription desc, Hashtable locationPairs,
            XMLEntityResolver entityResolver) throws IOException {
        String loc = null;
        // we consider the schema location properties for import
        if (desc.getContextType() == XSDDescription.CONTEXT_IMPORT ||
                desc.fromInstance()) {
            // use empty string as the key for absent namespace
            String namespace = desc.getTargetNamespace();
            String ns = namespace == null ? XMLSymbols.EMPTY_STRING : namespace;
            // get the location hint for that namespace
            LocationArray tempLA = (LocationArray)locationPairs.get(ns);
            if(tempLA != null)
                loc = tempLA.getFirstLocation();
        }
        
        // if it's not import, or if the target namespace is not set
        // in the schema location properties, use location hint
        if (loc == null) {
            String[] hints = desc.getLocationHints();
            if (hints != null && hints.length > 0)
                loc = hints[0];
        }
        
        String expandedLoc = XMLEntityManager.expandSystemId(loc, desc.getBaseSystemId(), false);
        desc.setLiteralSystemId(loc);
        desc.setExpandedSystemId(expandedLoc);
        return entityResolver.resolveEntity(desc);
    }
    
    // add external schema locations to the location pairs
    public static void processExternalHints(String sl, String nsl,
            Hashtable locations,
            XMLErrorReporter er) {
        if (sl != null) {
            try {
                // get the attribute decl for xsi:schemaLocation
                // because external schema location property has the same syntax
                // as xsi:schemaLocation
                XSAttributeDecl attrDecl = SchemaGrammar.SG_XSI.getGlobalAttributeDecl(SchemaSymbols.XSI_SCHEMALOCATION);
                // validation the string value to get the list of URI's
                attrDecl.fType.validate(sl, null, null);
                if (!tokenizeSchemaLocationStr(sl, locations, null)) {
                    // report warning (odd number of items)
                    er.reportError(XSMessageFormatter.SCHEMA_DOMAIN,
                            "SchemaLocation",
                            new Object[]{sl},
                            XMLErrorReporter.SEVERITY_WARNING);
                }
            }
            catch (InvalidDatatypeValueException ex) {
                // report warning (not list of URI's)
                er.reportError(XSMessageFormatter.SCHEMA_DOMAIN,
                        ex.getKey(), ex.getArgs(),
                        XMLErrorReporter.SEVERITY_WARNING);
            }
        }
        
        if (nsl != null) {
            try {
                // similarly for no ns schema location property
                XSAttributeDecl attrDecl = SchemaGrammar.SG_XSI.getGlobalAttributeDecl(SchemaSymbols.XSI_NONAMESPACESCHEMALOCATION);
                attrDecl.fType.validate(nsl, null, null);
                LocationArray la = ((LocationArray)locations.get(XMLSymbols.EMPTY_STRING));
                if(la == null) {
                    la = new LocationArray();
                    locations.put(XMLSymbols.EMPTY_STRING, la);
                }
                la.addLocation(nsl);
            }
            catch (InvalidDatatypeValueException ex) {
                // report warning (not a URI)
                er.reportError(XSMessageFormatter.SCHEMA_DOMAIN,
                        ex.getKey(), ex.getArgs(),
                        XMLErrorReporter.SEVERITY_WARNING);
            }
        }
    }
    // this method takes a SchemaLocation string.
    // If an error is encountered, false is returned;
    // otherwise, true is returned.  In either case, locations
    // is augmented to include as many tokens as possible.
    // @param schemaStr     The schemaLocation string to tokenize
    // @param locations     Hashtable mapping namespaces to LocationArray objects holding lists of locaitons
    // @return true if no problems; false if string could not be tokenized
    public static boolean tokenizeSchemaLocationStr(String schemaStr, Hashtable locations, String base) {
        if (schemaStr!= null) {
            StringTokenizer t = new StringTokenizer(schemaStr, " \n\t\r");
            String namespace, location;
            while (t.hasMoreTokens()) {
                namespace = t.nextToken ();
                if (!t.hasMoreTokens()) {
                    return false; // error!
                }
                location = t.nextToken();
                LocationArray la = ((LocationArray)locations.get(namespace));
                if(la == null) {
                    la = new LocationArray();
                    locations.put(namespace, la);
                }
                if (base != null) {
                    try {
                        location = XMLEntityManager.expandSystemId(location, base, false);
                    } catch (MalformedURIException e) {
                    }
                }
                la.addLocation(location);
            }
        }
        return true;
    } // tokenizeSchemaLocation(String, Hashtable):  boolean
    
    
Translate the various JAXP SchemaSource property types to XNI
XMLInputSource.  Valid types are: String, org.xml.sax.InputSource,
InputStream, File, or Object[] of any of previous types.
REVISIT:  the JAXP 1.2 spec is less than clear as to whether this property
should be available to imported schemas.  I have assumed
that it should.  - NG
Note: all JAXP schema files will be checked for full-schema validity if the feature was set up
/**
     * Translate the various JAXP SchemaSource property types to XNI
     * XMLInputSource.  Valid types are: String, org.xml.sax.InputSource,
     * InputStream, File, or Object[] of any of previous types.
     * REVISIT:  the JAXP 1.2 spec is less than clear as to whether this property
     * should be available to imported schemas.  I have assumed
     * that it should.  - NG
     * Note: all JAXP schema files will be checked for full-schema validity if the feature was set up
     * 
     */
    private void processJAXPSchemaSource(Hashtable locationPairs) throws IOException {
        fJAXPProcessed = true;
        if (fJAXPSource == null) {
            return;
        }
        
        Class componentType = fJAXPSource.getClass().getComponentType();
        XMLInputSource xis = null;
        String sid = null;
        if (componentType == null) {
            // Not an array
            if (fJAXPSource instanceof InputStream ||
                    fJAXPSource instanceof InputSource) {
                SchemaGrammar g = (SchemaGrammar)fJAXPCache.get(fJAXPSource);
                if (g != null) {
                    fGrammarBucket.putGrammar(g);
                    return;
                }
            }
            fXSDDescription.reset();
            xis = xsdToXMLInputSource(fJAXPSource);
            sid = xis.getSystemId();
            fXSDDescription.fContextType = XSDDescription.CONTEXT_PREPARSE;
            if (sid != null) {
                fXSDDescription.setBaseSystemId(xis.getBaseSystemId());
                fXSDDescription.setLiteralSystemId(sid);
                fXSDDescription.setExpandedSystemId(sid);
                fXSDDescription.fLocationHints = new String[]{sid};
            }
            SchemaGrammar g = loadSchema(fXSDDescription, xis, locationPairs);
            // it is possible that we won't be able to resolve JAXP schema-source location
            if (g != null) {
                if (fJAXPSource instanceof InputStream ||
                        fJAXPSource instanceof InputSource) {
                    fJAXPCache.put(fJAXPSource, g);
                    if (fIsCheckedFully) {
                        XSConstraints.fullSchemaChecking(fGrammarBucket, fSubGroupHandler, fCMBuilder, fErrorReporter);
                    }
                }
                fGrammarBucket.putGrammar(g);
            }
            return;
        } 
        else if ( (componentType != Object.class) &&
                (componentType != String.class) &&
                (componentType != File.class) &&
                (componentType != InputStream.class) &&
                (componentType != InputSource.class) &&
                !File.class.isAssignableFrom(componentType) &&
                !InputStream.class.isAssignableFrom(componentType) &&
                !InputSource.class.isAssignableFrom(componentType) &&
                !componentType.isInterface()
        ) {
            // Not an Object[], String[], File[], InputStream[], InputSource[]
            MessageFormatter mf = fErrorReporter.getMessageFormatter(XSMessageFormatter.SCHEMA_DOMAIN);
            throw new XMLConfigurationException(
                    XMLConfigurationException.NOT_SUPPORTED, 
                    mf.formatMessage(fErrorReporter.getLocale(), "jaxp12-schema-source-type.2",
                    new Object [] {componentType.getName()}));
        }
        
        // JAXP spec. allow []s of type String, File, InputStream,
        // InputSource also, apart from [] of type Object.
        Object[] objArr = (Object[]) fJAXPSource;
        // make local vector for storing target namespaces of schemasources specified in object arrays.
        ArrayList jaxpSchemaSourceNamespaces = new ArrayList();
        for (int i = 0; i < objArr.length; i++) {
            if (objArr[i] instanceof InputStream ||
                    objArr[i] instanceof InputSource) {
                SchemaGrammar g = (SchemaGrammar)fJAXPCache.get(objArr[i]);
                if (g != null) {
                    fGrammarBucket.putGrammar(g);
                    continue;
                }
            }
            fXSDDescription.reset();
            xis = xsdToXMLInputSource(objArr[i]);
            sid = xis.getSystemId();
            fXSDDescription.fContextType = XSDDescription.CONTEXT_PREPARSE;
            if (sid != null) {
                fXSDDescription.setBaseSystemId(xis.getBaseSystemId());
                fXSDDescription.setLiteralSystemId(sid);
                fXSDDescription.setExpandedSystemId(sid);
                fXSDDescription.fLocationHints = new String[]{sid};
            }
            String targetNamespace = null ;
            // load schema
            SchemaGrammar grammar = fSchemaHandler.parseSchema(xis,fXSDDescription, locationPairs);
            
            if (fIsCheckedFully) {
                XSConstraints.fullSchemaChecking(fGrammarBucket, fSubGroupHandler, fCMBuilder, fErrorReporter);
            }                                   
            if (grammar != null) {
                targetNamespace = grammar.getTargetNamespace();
                if (jaxpSchemaSourceNamespaces.contains(targetNamespace)) {
                    // when an array of objects is passed it is illegal to have two schemas that share same namespace.
                    MessageFormatter mf = fErrorReporter.getMessageFormatter(XSMessageFormatter.SCHEMA_DOMAIN);
                    throw new java.lang.IllegalArgumentException(mf.formatMessage(fErrorReporter.getLocale(), 
                            "jaxp12-schema-source-ns", null));
                }
                else {
                    jaxpSchemaSourceNamespaces.add(targetNamespace) ;
                }
                if (objArr[i] instanceof InputStream ||
                        objArr[i] instanceof InputSource) {
                    fJAXPCache.put(objArr[i], grammar);
                }
                fGrammarBucket.putGrammar(grammar);
            }
            else {
                //REVISIT: What should be the acutal behavior if grammar can't be loaded as specified in schema source?
            }
        }
    }//processJAXPSchemaSource
    
    private XMLInputSource xsdToXMLInputSource(Object val) {
        if (val instanceof String) {
            // String value is treated as a URI that is passed through the
            // EntityResolver
            String loc = (String) val;          
            fXSDDescription.reset();
            fXSDDescription.setValues(null, loc, null, null);
            XMLInputSource xis = null;
            try {
                xis = fEntityManager.resolveEntity(fXSDDescription);
            } 
            catch (IOException ex) {
                fErrorReporter.reportError(XSMessageFormatter.SCHEMA_DOMAIN,
                        "schema_reference.4",
                        new Object[] { loc }, XMLErrorReporter.SEVERITY_ERROR);
            }
            if (xis == null) {
                // REVISIT: can this happen?
                // Treat value as a URI and pass in as systemId
                return new XMLInputSource(null, loc, null);
            }
            return xis;
        } 
        else if (val instanceof InputSource) {
            return saxToXMLInputSource((InputSource) val);
        } 
        else if (val instanceof InputStream) {
            return new XMLInputSource(null, null, null,
                    (InputStream) val, null);
        } 
        else if (val instanceof File) {
            File file = (File) val;
            String escapedURI = FilePathToURI.filepath2URI(file.getAbsolutePath());
            InputStream is = null;
            try {
                is = new BufferedInputStream(new FileInputStream(file));
            } 
            catch (FileNotFoundException ex) {
                fErrorReporter.reportError(XSMessageFormatter.SCHEMA_DOMAIN,
                        "schema_reference.4", new Object[] { file.toString() },
                        XMLErrorReporter.SEVERITY_ERROR);
            }
            return new XMLInputSource(null, escapedURI, null, is, null);
        }
        MessageFormatter mf = fErrorReporter.getMessageFormatter(XSMessageFormatter.SCHEMA_DOMAIN);
        throw new XMLConfigurationException(
                XMLConfigurationException.NOT_SUPPORTED, 
                mf.formatMessage(fErrorReporter.getLocale(), "jaxp12-schema-source-type.1",
                new Object [] {val != null ? val.getClass().getName() : "null"}));
    }
    
    
    //Convert a SAX InputSource to an equivalent XNI XMLInputSource
    
    private static XMLInputSource saxToXMLInputSource(InputSource sis) {
        String publicId = sis.getPublicId();
        String systemId = sis.getSystemId();
        
        Reader charStream = sis.getCharacterStream();
        if (charStream != null) {
            return new XMLInputSource(publicId, systemId, null, charStream,
                    null);
        }
        
        InputStream byteStream = sis.getByteStream();
        if (byteStream != null) {
            return new XMLInputSource(publicId, systemId, null, byteStream,
                    sis.getEncoding());
        }
        
        return new XMLInputSource(publicId, systemId, null);
    }
    
    static class LocationArray{
        
        int length ;
        String [] locations = new String[2];
        
        public void resize(int oldLength , int newLength){
            String [] temp = new String[newLength] ;
            System.arraycopy(locations, 0, temp, 0, Math.min(oldLength, newLength));
            locations = temp ;
            length = Math.min(oldLength, newLength);
        }
        
        public void addLocation(String location){
            if(length >= locations.length ){
                resize(length, Math.max(1, length*2));
            }
            locations[length++] = location;
        }//setLocation()
        
        public String [] getLocationArray(){
            if(length < locations.length ){
                resize(locations.length, length);
            }
            return locations;
        }//getLocationArray()
        
        public String getFirstLocation(){
            return length > 0 ? locations[0] : null;
        }
        
        public int getLength(){
            return length ;
        }
        
    } //locationArray
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xni.parser.XMLComponent#getFeatureDefault(java.lang.String)
     */
    public Boolean getFeatureDefault(String featureId) {
        if (featureId.equals(AUGMENT_PSVI)){
            return Boolean.TRUE;
        }
        return null;
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xni.parser.XMLComponent#getPropertyDefault(java.lang.String)
     */
    public Object getPropertyDefault(String propertyId) {
        // TODO Auto-generated method stub
        return null;
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xni.parser.XMLComponent#reset(org.apache.xerces.xni.parser.XMLComponentManager)
     */
    public void reset(XMLComponentManager componentManager) throws XMLConfigurationException {
        
        fGrammarBucket.reset();
        
        fSubGroupHandler.reset();		
        
        if (!fSettingsChanged || !parserSettingsUpdated(componentManager)) {
            // need to reprocess JAXP schema sources
            fJAXPProcessed = false;
            // reinitialize grammar bucket
            initGrammarBucket();
            if (fDeclPool != null) {
                fDeclPool.reset();
            }
            return;           
        } 
        
        // get registered entity manager to be able to resolve JAXP schema-source property:
        // Note: in case XMLSchemaValidator has created the loader, 
        // the entity manager property is null
        fEntityManager = (XMLEntityManager)componentManager.getProperty(ENTITY_MANAGER);      
        
        // get the error reporter
        fErrorReporter = (XMLErrorReporter)componentManager.getProperty(ERROR_REPORTER);
        
        // Determine schema dv factory to use
        SchemaDVFactory dvFactory = null;
        try {
            dvFactory = (SchemaDVFactory)componentManager.getProperty(SCHEMA_DV_FACTORY);
        } catch (XMLConfigurationException e) {
        }
        if (dvFactory == null) {
            if (fDefaultSchemaDVFactory == null) {
                fDefaultSchemaDVFactory = SchemaDVFactory.getInstance();
            }
            dvFactory = fDefaultSchemaDVFactory;
        }
        fSchemaHandler.setDVFactory(dvFactory);

        // get schema location properties
        try {
            fExternalSchemas = (String) componentManager.getProperty(SCHEMA_LOCATION);
            fExternalNoNSSchema =
                (String) componentManager.getProperty(SCHEMA_NONS_LOCATION);
        } catch (XMLConfigurationException e) {
            fExternalSchemas = null;
            fExternalNoNSSchema = null;
        }
        // get JAXP sources if available
        try {
            fJAXPSource = componentManager.getProperty(JAXP_SCHEMA_SOURCE);
            fJAXPProcessed = false;
            
        } catch (XMLConfigurationException e) {
            fJAXPSource = null;
            fJAXPProcessed = false;
        }
        
        // clear grammars, and put the one for schema namespace there
        try {
            fGrammarPool = (XMLGrammarPool) componentManager.getProperty(XMLGRAMMAR_POOL);
        } catch (XMLConfigurationException e) {
            fGrammarPool = null;
        }
        initGrammarBucket();

        boolean psvi = true;
        try {
            psvi = componentManager.getFeature(AUGMENT_PSVI);
        } catch (XMLConfigurationException e) {
            psvi = false;
        }
        
        // Only use the decl pool when there is no chance that the schema
        // components will be exposed or cached.
        // TODO: when someone calls loadGrammar(XMLInputSource), the schema is
        // always exposed even without the use of a grammar pool.
        // Disabling the "decl pool" feature for now until we understand when
        // it can be safely used.
        if (!psvi && fGrammarPool == null && false) {
            if (fDeclPool != null) {
                fDeclPool.reset();
            }
            else {
                fDeclPool = new XSDeclarationPool();
            }
            fCMBuilder.setDeclPool(fDeclPool);
            fSchemaHandler.setDeclPool(fDeclPool);
            if (dvFactory instanceof SchemaDVFactoryImpl) {
                fDeclPool.setDVFactory((SchemaDVFactoryImpl)dvFactory);
                ((SchemaDVFactoryImpl)dvFactory).setDeclPool(fDeclPool);
            }
        } else {
            fCMBuilder.setDeclPool(null);
            fSchemaHandler.setDeclPool(null);
            if (dvFactory instanceof SchemaDVFactoryImpl) {
                ((SchemaDVFactoryImpl)dvFactory).setDeclPool(null);
            }
        }
        
        // get continue-after-fatal-error feature
        try {
            boolean fatalError = componentManager.getFeature(CONTINUE_AFTER_FATAL_ERROR);
            fErrorReporter.setFeature(CONTINUE_AFTER_FATAL_ERROR, fatalError);
        } catch (XMLConfigurationException e) {
        }
        // set full validation to false        
        try {
            fIsCheckedFully = componentManager.getFeature(SCHEMA_FULL_CHECKING);
        }
        catch (XMLConfigurationException e){
            fIsCheckedFully = false;
        }
        // get generate-synthetic-annotations feature
        try {
            fSchemaHandler.setGenerateSyntheticAnnotations(componentManager.getFeature(GENERATE_SYNTHETIC_ANNOTATIONS));
        }
        catch (XMLConfigurationException e) {
            fSchemaHandler.setGenerateSyntheticAnnotations(false);
        }
        fSchemaHandler.reset(componentManager);		 
    }
    
    private boolean parserSettingsUpdated(XMLComponentManager componentManager) {
        // If the component manager is the loader config don't bother querying it since it doesn't 
        // recognize the PARSER_SETTINGS feature. Prevents an XMLConfigurationException from being 
        // thrown.
        if (componentManager != fLoaderConfig) {
            try {
                return componentManager.getFeature(PARSER_SETTINGS);     
            }
            catch (XMLConfigurationException e) {}
        }
        return true;
    }
    
    private void initGrammarBucket(){
        if(fGrammarPool != null) {
            Grammar [] initialGrammars = fGrammarPool.retrieveInitialGrammarSet(XMLGrammarDescription.XML_SCHEMA);
            final int length = (initialGrammars != null) ? initialGrammars.length : 0;
            for (int i = 0; i < length; ++i) {
                // put this grammar into the bucket, along with grammars
                // imported by it (directly or indirectly)
                if (!fGrammarBucket.putGrammar((SchemaGrammar)(initialGrammars[i]), true)) {
                    // REVISIT: a conflict between new grammar(s) and grammars
                    // in the bucket. What to do? A warning? An exception?
                    fErrorReporter.reportError(XSMessageFormatter.SCHEMA_DOMAIN,
                            "GrammarConflict", null,
                            XMLErrorReporter.SEVERITY_WARNING);
                }
            }
        }
    }
    
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xs.XSLoader#getConfig()
     */
    public DOMConfiguration getConfig() {
        return this;
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xs.XSLoader#load(org.w3c.dom.ls.LSInput)
     */
    public XSModel load(LSInput is) {
        try {
            Grammar g = loadGrammar(dom2xmlInputSource(is));
            return ((XSGrammar) g).toXSModel();
        } catch (Exception e) {
            reportDOMFatalError(e);
            return null;
        }
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xs.XSLoader#loadInputList(org.apache.xerces.xs.LSInputList)
     */
    public XSModel loadInputList(LSInputList is) {
        int length = is.getLength();
        SchemaGrammar[] gs = new SchemaGrammar[length];
        for (int i = 0; i < length; i++) {
            try {
                gs[i] = (SchemaGrammar) loadGrammar(dom2xmlInputSource(is.item(i)));
            } catch (Exception e) {
                reportDOMFatalError(e);
                return null;
            }
        }
        return new XSModelImpl(gs);
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xs.XSLoader#loadURI(java.lang.String)
     */
    public XSModel loadURI(String uri) {
        try {
            Grammar g = loadGrammar(new XMLInputSource(null, uri, null));
            return ((XSGrammar)g).toXSModel();
        }
        catch (Exception e){
            reportDOMFatalError(e);
            return null;
        }
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.xs.XSLoader#loadURIList(org.apache.xerces.xs.StringList)
     */
    public XSModel loadURIList(StringList uriList) {
        int length = uriList.getLength();
        SchemaGrammar[] gs = new SchemaGrammar[length];
        for (int i = 0; i < length; i++) {
            try {
                gs[i] =
                    (SchemaGrammar) loadGrammar(new XMLInputSource(null, uriList.item(i), null));
            } catch (Exception e) {
                reportDOMFatalError(e);
                return null;
            }
        }
        return new XSModelImpl(gs);
    }
    
    void reportDOMFatalError(Exception e) {
                if (fErrorHandler != null) {
                    DOMErrorImpl error = new DOMErrorImpl();
                    error.fException = e;
                    error.fMessage = e.getMessage();
                    error.fSeverity = DOMError.SEVERITY_FATAL_ERROR;
                    fErrorHandler.getErrorHandler().handleError(error);
                }
            }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.dom3.DOMConfiguration#canSetParameter(java.lang.String, java.lang.Object)
     */
    public boolean canSetParameter(String name, Object value) {
        if(value instanceof Boolean){
            if (name.equals(Constants.DOM_VALIDATE) ||
                name.equals(SCHEMA_FULL_CHECKING) ||
                name.equals(VALIDATE_ANNOTATIONS) ||
                name.equals(CONTINUE_AFTER_FATAL_ERROR) ||
                name.equals(ALLOW_JAVA_ENCODINGS) ||
                name.equals(STANDARD_URI_CONFORMANT_FEATURE) ||
                name.equals(GENERATE_SYNTHETIC_ANNOTATIONS) ||
                name.equals(HONOUR_ALL_SCHEMALOCATIONS) ||
                name.equals(NAMESPACE_GROWTH) ||
                name.equals(TOLERATE_DUPLICATES)) {
                return true;
                
            }
            return false;			
        }
        if (name.equals(Constants.DOM_ERROR_HANDLER) ||
            name.equals(Constants.DOM_RESOURCE_RESOLVER) ||
            name.equals(SYMBOL_TABLE) ||
            name.equals(ERROR_REPORTER) ||
            name.equals(ERROR_HANDLER) ||
            name.equals(ENTITY_RESOLVER) ||
            name.equals(XMLGRAMMAR_POOL) ||
            name.equals(SCHEMA_LOCATION) ||
            name.equals(SCHEMA_NONS_LOCATION) ||
            name.equals(JAXP_SCHEMA_SOURCE) ||
            name.equals(SCHEMA_DV_FACTORY)) {
            return true;
        }
        return false;
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.dom3.DOMConfiguration#getParameter(java.lang.String)
     */
    public Object getParameter(String name) throws DOMException {
        
        if (name.equals(Constants.DOM_ERROR_HANDLER)){
            return (fErrorHandler != null) ? fErrorHandler.getErrorHandler() : null;
        }
        else if (name.equals(Constants.DOM_RESOURCE_RESOLVER)) {
            return (fResourceResolver != null) ? fResourceResolver.getEntityResolver() : null;
        }
        
        try {
            boolean feature = getFeature(name);
            return (feature) ? Boolean.TRUE : Boolean.FALSE;
        } catch (Exception e) {
            Object property;
            try {
                property = getProperty(name);
                return property;
            } catch (Exception ex) {
                String msg =
                    DOMMessageFormatter.formatMessage(
                            DOMMessageFormatter.DOM_DOMAIN,
                            "FEATURE_NOT_SUPPORTED",
                            new Object[] { name });
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
            }
        }
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.dom3.DOMConfiguration#getParameterNames()
     */
    public DOMStringList getParameterNames() {
        if (fRecognizedParameters == null){
            ArrayList v = new ArrayList();
            v.add(Constants.DOM_VALIDATE);
            v.add(Constants.DOM_ERROR_HANDLER);
            v.add(Constants.DOM_RESOURCE_RESOLVER);
            v.add(SYMBOL_TABLE);
            v.add(ERROR_REPORTER);
            v.add(ERROR_HANDLER);
            v.add(ENTITY_RESOLVER);
            v.add(XMLGRAMMAR_POOL);
            v.add(SCHEMA_LOCATION);
            v.add(SCHEMA_NONS_LOCATION);
            v.add(JAXP_SCHEMA_SOURCE);
            v.add(SCHEMA_FULL_CHECKING);
            v.add(CONTINUE_AFTER_FATAL_ERROR);
            v.add(ALLOW_JAVA_ENCODINGS);
            v.add(STANDARD_URI_CONFORMANT_FEATURE);
            v.add(VALIDATE_ANNOTATIONS);
            v.add(GENERATE_SYNTHETIC_ANNOTATIONS);
            v.add(HONOUR_ALL_SCHEMALOCATIONS);
            v.add(NAMESPACE_GROWTH);
            v.add(TOLERATE_DUPLICATES);
            fRecognizedParameters = new DOMStringListImpl(v);      	
        }
        return fRecognizedParameters;
    }
    
    /* (non-Javadoc)
     * @see org.apache.xerces.dom3.DOMConfiguration#setParameter(java.lang.String, java.lang.Object)
     */
    public void setParameter(String name, Object value) throws DOMException {
        if (value instanceof Boolean) {
            boolean state = ((Boolean) value).booleanValue();
            if (name.equals("validate") && state) {
                return;
            }
            try {
                setFeature(name, state);
            } catch (Exception e) {
                String msg =
                    DOMMessageFormatter.formatMessage(
                            DOMMessageFormatter.DOM_DOMAIN,
                            "FEATURE_NOT_SUPPORTED",
                            new Object[] { name });
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
            }
            return;
        }
        if (name.equals(Constants.DOM_ERROR_HANDLER)) {
            if (value instanceof DOMErrorHandler) {
                try {
                    fErrorHandler = new DOMErrorHandlerWrapper((DOMErrorHandler) value);
                    setErrorHandler(fErrorHandler);
                } catch (XMLConfigurationException e) {
                }
            } else {
                // REVISIT: type mismatch
                String msg =
                    DOMMessageFormatter.formatMessage(
                            DOMMessageFormatter.DOM_DOMAIN,
                            "FEATURE_NOT_SUPPORTED",
                            new Object[] { name });
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
            }
            return;
            
        }
        if (name.equals(Constants.DOM_RESOURCE_RESOLVER)) {
            if (value instanceof LSResourceResolver) {
                try {
                    fResourceResolver = new DOMEntityResolverWrapper((LSResourceResolver) value);
                    setEntityResolver(fResourceResolver);
                } 
                catch (XMLConfigurationException e) {}
            } else {
                // REVISIT: type mismatch
                String msg =
                    DOMMessageFormatter.formatMessage(
                            DOMMessageFormatter.DOM_DOMAIN,
                            "FEATURE_NOT_SUPPORTED",
                            new Object[] { name });
                throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
            }
            return;
        }
        
        try {
            setProperty(name, value);
        } catch (Exception ex) {
            
            String msg =
                DOMMessageFormatter.formatMessage(
                        DOMMessageFormatter.DOM_DOMAIN,
                        "FEATURE_NOT_SUPPORTED",
                        new Object[] { name });
            throw new DOMException(DOMException.NOT_SUPPORTED_ERR, msg);
            
        }
        
    }
    
	XMLInputSource dom2xmlInputSource(LSInput is) {
        // need to wrap the LSInput with an XMLInputSource
        XMLInputSource xis = null;
        
        /**
         * An LSParser looks at inputs specified in LSInput in
         * the following order: characterStream, byteStream,
         * stringData, systemId, publicId. For consistency
         * have the same behaviour for XSLoader.
         */
        
        // check whether there is a Reader
        // according to DOM, we need to treat such reader as "UTF-16".
        if (is.getCharacterStream() != null) {
            xis = new XMLInputSource(is.getPublicId(), is.getSystemId(),
                    is.getBaseURI(), is.getCharacterStream(),
            "UTF-16");
        }
        // check whether there is an InputStream
        else if (is.getByteStream() != null) {
            xis = new XMLInputSource(is.getPublicId(), is.getSystemId(),
                    is.getBaseURI(), is.getByteStream(),
                    is.getEncoding());
        }
        // if there is a string data, use a StringReader
        // according to DOM, we need to treat such data as "UTF-16".
        else if (is.getStringData() != null && is.getStringData().length() != 0) {
            xis = new XMLInputSource(is.getPublicId(), is.getSystemId(),
                    is.getBaseURI(), new StringReader(is.getStringData()),
            "UTF-16");
        }
        // otherwise, just use the public/system/base Ids
        else {
            xis = new XMLInputSource(is.getPublicId(), is.getSystemId(),
                    is.getBaseURI());
        }
        
        return xis;
    }
	
    // Implements XSElementDeclHelper interface
    public XSElementDecl getGlobalElementDecl(QName element) {
        SchemaGrammar sGrammar = fGrammarBucket.getGrammar(element.uri);
        if (sGrammar != null) {
            return sGrammar.getGlobalElementDecl(element.localpart);
        }
        return null;
    }
    
} // XMLGrammarLoader