--- a/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/XMLSchemaLoader.java	Thu Jul 30 20:29:33 2015 +0100
+++ b/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/XMLSchemaLoader.java	Fri Oct 23 16:41:06 2015 -0400
@@ -65,6 +65,8 @@
 import com.sun.org.apache.xerces.internal.xs.StringList;
 import com.sun.org.apache.xerces.internal.xs.XSLoader;
 import com.sun.org.apache.xerces.internal.xs.XSModel;
+import java.util.HashMap;
+import java.util.Map;
 import org.w3c.dom.DOMConfiguration;
 import org.w3c.dom.DOMError;
 import org.w3c.dom.DOMErrorHandler;
@@ -236,7 +238,7 @@
     private CMBuilder fCMBuilder;
     private XSDDescription fXSDDescription = new XSDDescription();
     
-    private Hashtable fJAXPCache;
+    private Map fJAXPCache;
     private Locale fLocale = Locale.getDefault();
     
     // XSLoader attributes
@@ -323,8 +325,10 @@
         }
         fCMBuilder = builder;
         fSchemaHandler = new XSDHandler(fGrammarBucket);
-        fDeclPool = new XSDeclarationPool();
-        fJAXPCache = new Hashtable();
+        if (fDeclPool != null) {
+            fDeclPool.reset();
+        }
+        fJAXPCache = new HashMap();
         
         fSettingsChanged = true;
     }
@@ -522,7 +526,7 @@
         desc.setBaseSystemId(source.getBaseSystemId());
         desc.setLiteralSystemId( source.getSystemId());
         // none of the other fields make sense for preparsing
-        Hashtable locationPairs = new Hashtable();
+        Map locationPairs = new HashMap();
         // Process external schema location properties.
         // We don't call tokenizeSchemaLocationStr here, because we also want
         // to check whether the values are valid URI.
@@ -554,7 +558,7 @@
      */
     SchemaGrammar loadSchema(XSDDescription desc,
             XMLInputSource source,
-            Hashtable locationPairs) throws IOException, XNIException {
+            Map locationPairs) throws IOException, XNIException {
         
         // this should only be done once per invocation of this object;
         // unless application alters JAXPSource in the mean time.
@@ -578,7 +582,7 @@
      * @return
      * @throws IOException
      */
-    public static XMLInputSource resolveDocument(XSDDescription desc, Hashtable locationPairs,
+    public static XMLInputSource resolveDocument(XSDDescription desc, Map locationPairs,
             XMLEntityResolver entityResolver) throws IOException {
         String loc = null;
         // we consider the schema location properties for import
@@ -609,7 +613,7 @@
     
     // add external schema locations to the location pairs
     public static void processExternalHints(String sl, String nsl,
-            Hashtable locations,
+            Map locations,
             XMLErrorReporter er) {
         if (sl != null) {
             try {
@@ -660,9 +664,9 @@
     // 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
+    // @param locations     HashMap 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) {
+    public static boolean tokenizeSchemaLocationStr(String schemaStr, Map locations) {
         if (schemaStr!= null) {
             StringTokenizer t = new StringTokenizer(schemaStr, " \n\t\r");
             String namespace, location;
@@ -681,7 +685,7 @@
             }
         }
         return true;
-    } // tokenizeSchemaLocation(String, Hashtable):  boolean
+    } // tokenizeSchemaLocation(String, HashMap):  boolean
     
     /**
      * Translate the various JAXP SchemaSource property types to XNI
@@ -693,7 +697,7 @@
      * 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 {
+    private void processJAXPSchemaSource(Map locationPairs) throws IOException {
         fJAXPProcessed = true;
         if (fJAXPSource == null) {
             return;
@@ -966,7 +970,12 @@
         }
         
         if (!psvi) {
-            fDeclPool.reset();
+            if (fDeclPool != null) {
+                fDeclPool.reset();
+            }
+            else {
+                fDeclPool = new XSDeclarationPool();
+            }
             fCMBuilder.setDeclPool(fDeclPool);
             fSchemaHandler.setDeclPool(fDeclPool);
         } else {

--- a/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/XMLSchemaValidator.java	Thu Jul 30 20:29:33 2015 +0100
+++ b/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/XMLSchemaValidator.java	Fri Oct 23 16:41:06 2015 -0400
@@ -78,8 +78,6 @@
 import com.sun.org.apache.xerces.internal.xs.XSConstants;
 import com.sun.org.apache.xerces.internal.xs.XSObjectList;
 import com.sun.org.apache.xerces.internal.xs.XSTypeDefinition;
-import org.xml.sax.SAXNotRecognizedException;
-import org.xml.sax.SAXNotSupportedException;
 import com.sun.org.apache.xerces.internal.parsers.XMLParser;
 
 /**

--- a/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/XSGrammarBucket.java	Thu Jul 30 20:29:33 2015 +0100
+++ b/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/XSGrammarBucket.java	Fri Oct 23 16:41:06 2015 -0400
@@ -20,8 +20,9 @@
 
 package com.sun.org.apache.xerces.internal.impl.xs;
 
-import java.util.Hashtable;
 import java.util.Enumeration;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.Vector;
 
 /**
@@ -38,7 +39,7 @@
     /**
      * Hashtable that maps between Namespace and a Grammar
      */
-    Hashtable fGrammarRegistry = new Hashtable();
+    Map<String, SchemaGrammar> fGrammarRegistry = new HashMap();
     SchemaGrammar fNoNSGrammar = null;
 
     /**
@@ -145,10 +146,11 @@
         int count = fGrammarRegistry.size() + (fNoNSGrammar==null ? 0 : 1);
         SchemaGrammar[] grammars = new SchemaGrammar[count];
         // get grammars with target namespace
-        Enumeration schemas = fGrammarRegistry.elements();
         int i = 0;
-        while (schemas.hasMoreElements())
-            grammars[i++] = (SchemaGrammar)schemas.nextElement();
+        for(Map.Entry<String, SchemaGrammar> entry : fGrammarRegistry.entrySet()){
+            grammars[i++] = entry.getValue();
+        }
+
         // add the grammar without target namespace, if any
         if (fNoNSGrammar != null)
             grammars[count-1] = fNoNSGrammar;

--- a/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/traversers/XSAttributeChecker.java	Thu Jul 30 20:29:33 2015 +0100
+++ b/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/traversers/XSAttributeChecker.java	Fri Oct 23 16:41:06 2015 -0400
@@ -20,11 +20,6 @@
 
 package com.sun.org.apache.xerces.internal.impl.xs.traversers;
 
-import java.util.Enumeration;
-import java.util.Hashtable;
-import java.util.StringTokenizer;
-import java.util.Vector;
-
 import com.sun.org.apache.xerces.internal.impl.dv.InvalidDatatypeValueException;
 import com.sun.org.apache.xerces.internal.impl.dv.XSSimpleType;
 import com.sun.org.apache.xerces.internal.impl.xs.SchemaGrammar;
@@ -41,6 +36,12 @@
 import com.sun.org.apache.xerces.internal.utils.XMLSecurityManager;
 import com.sun.org.apache.xerces.internal.xni.QName;
 import com.sun.org.apache.xerces.internal.xs.XSConstants;
+import java.util.Enumeration;
+import java.util.Hashtable;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.StringTokenizer;
+import java.util.Vector;
 import org.w3c.dom.Attr;
 import org.w3c.dom.Element;
 
@@ -144,9 +145,9 @@
 
     // used to store the map from element name to attribute list
     // for 14 global elements
-    private static final Hashtable fEleAttrsMapG = new Hashtable(29);
+    private static final Map fEleAttrsMapG = new HashMap(29);
     // for 39 local elememnts
-    private static final Hashtable fEleAttrsMapL = new Hashtable(79);
+    private static final Map fEleAttrsMapL = new HashMap(79);
 
     // used to initialize fEleAttrsMap
     // step 1: all possible data types
@@ -967,7 +968,7 @@
     protected SymbolTable fSymbolTable = null;
 
     // used to store the mapping from processed element to attributes
-    protected Hashtable fNonSchemaAttrs = new Hashtable();
+    protected Map<String, Vector<String>> fNonSchemaAttrs = new HashMap();
 
     // temprory vector, used to hold the namespace list
     protected Vector fNamespaceList = new Vector();
@@ -1033,7 +1034,7 @@
             reportSchemaError("s4s-elt-schema-ns", new Object[] {elName}, element);
         }
 
-        Hashtable eleAttrsMap = fEleAttrsMapG;
+        Map eleAttrsMap = fEleAttrsMapG;
         String lookupName = elName;
 
         // REVISIT: only local element and attribute are different from others.
@@ -1633,11 +1634,10 @@
     // REVISIT: pass the proper element node to reportSchemaError
     public void checkNonSchemaAttributes(XSGrammarBucket grammarBucket) {
         // for all attributes
-        Enumeration keys = fNonSchemaAttrs.keys();
         XSAttributeDecl attrDecl;
-        while (keys.hasMoreElements()) {
+        for (Map.Entry<String, Vector<String>> entry : fNonSchemaAttrs.entrySet()) {
             // get name, uri, localpart
-            String attrRName = (String)keys.nextElement();
+            String attrRName = entry.getKey();
             String attrURI = attrRName.substring(0,attrRName.indexOf(','));
             String attrLocal = attrRName.substring(attrRName.indexOf(',')+1);
             // find associated grammar
@@ -1653,7 +1653,7 @@
                 continue;
 
             // get all values appeared with this attribute name
-            Vector values = (Vector)fNonSchemaAttrs.get(attrRName);
+            Vector values = entry.getValue();
             String elName, attrVal;
             String attrName = (String)values.elementAt(0);
             // for each of the values
@@ -1881,9 +1881,9 @@
 }
 
 class LargeContainer extends Container {
-    Hashtable items;
+    Map items;
     LargeContainer(int size) {
-        items = new Hashtable(size*2+1);
+        items = new HashMap(size*2+1);
         values = new OneAttr[size];
     }
     void put(String key, OneAttr value) {

--- a/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/traversers/XSDHandler.java	Thu Jul 30 20:29:33 2015 +0100
+++ b/drop_included/jaxp_src/src/com/sun/org/apache/xerces/internal/impl/xs/traversers/XSDHandler.java	Fri Oct 23 16:41:06 2015 -0400
@@ -200,8 +200,6 @@
     
     //
     //protected data that can be accessable by any traverser
-    // stores <notation> decl
-    protected Hashtable fNotationRegistry = new Hashtable();
     
     protected XSDeclarationPool fDeclPool = null;
    
@@ -220,48 +218,41 @@
     // By asking the node for its ownerDocument and looking in
     // XSDocumentInfoRegistry we can easily get the corresponding
     // XSDocumentInfo object.
-    private Hashtable fUnparsedAttributeRegistry = new Hashtable();
-    private Hashtable fUnparsedAttributeGroupRegistry = new Hashtable();
-    private Hashtable fUnparsedElementRegistry = new Hashtable();
-    private Hashtable fUnparsedGroupRegistry = new Hashtable();
-    private Hashtable fUnparsedIdentityConstraintRegistry = new Hashtable();
-    private Hashtable fUnparsedNotationRegistry = new Hashtable();
-    private Hashtable fUnparsedTypeRegistry = new Hashtable();
-    // Compensation for the above hashtables to locate XSDocumentInfo, 
+    private boolean registryEmpty = true;
+    private Map<String, Element> fUnparsedAttributeRegistry = new HashMap();
+    private Map<String, Element> fUnparsedAttributeGroupRegistry =  new HashMap();
+    private Map<String, Element> fUnparsedElementRegistry =  new HashMap();
+    private Map<String, Element> fUnparsedGroupRegistry =  new HashMap();
+    private Map<String, Element> fUnparsedIdentityConstraintRegistry =  new HashMap();
+    private Map<String, Element> fUnparsedNotationRegistry =  new HashMap();
+    private Map<String, Element> fUnparsedTypeRegistry =  new HashMap();
+    // Compensation for the above map to locate XSDocumentInfo, 
     // Since we may take Schema Element directly, so can not get the
-    // corresponding XSDocumentInfo object just using above hashtables.
-    private Hashtable fUnparsedAttributeRegistrySub = new Hashtable();
-    private Hashtable fUnparsedAttributeGroupRegistrySub = new Hashtable();
-    private Hashtable fUnparsedElementRegistrySub = new Hashtable();
-    private Hashtable fUnparsedGroupRegistrySub = new Hashtable();
-    private Hashtable fUnparsedIdentityConstraintRegistrySub = new Hashtable();
-    private Hashtable fUnparsedNotationRegistrySub = new Hashtable();
-    private Hashtable fUnparsedTypeRegistrySub = new Hashtable();
+    // corresponding XSDocumentInfo object just using above maps.
+    private Map<String, XSDocumentInfo> fUnparsedAttributeRegistrySub =  new HashMap();
+    private Map<String, XSDocumentInfo> fUnparsedAttributeGroupRegistrySub =  new HashMap();
+    private Map<String, XSDocumentInfo> fUnparsedElementRegistrySub =  new HashMap();
+    private Map<String, XSDocumentInfo> fUnparsedGroupRegistrySub =  new HashMap();
+    private Map<String, XSDocumentInfo> fUnparsedIdentityConstraintRegistrySub =  new HashMap();
+    private Map<String, XSDocumentInfo> fUnparsedNotationRegistrySub =  new HashMap();
+    private Map<String, XSDocumentInfo> fUnparsedTypeRegistrySub =  new HashMap();
     
-    // this is keyed with a documentNode (or the schemaRoot nodes
-    // contained in the XSDocumentInfo objects) and its value is the
-    // XSDocumentInfo object corresponding to that document.
-    // Basically, the function of this registry is to be a link
-    // between the nodes we fetch from calls to the fUnparsed*
-    // arrays and the XSDocumentInfos they live in.
-    private Hashtable fXSDocumentInfoRegistry = new Hashtable();
-    
-    // this hashtable is keyed on by XSDocumentInfo objects.  Its values
+    // this map is keyed on by XSDocumentInfo objects.  Its values
     // are Vectors containing the XSDocumentInfo objects <include>d,
     // <import>ed or <redefine>d by the key XSDocumentInfo.
-    private Hashtable fDependencyMap = new Hashtable();
+    private Map<XSDocumentInfo, Vector> fDependencyMap = new HashMap();
     
-    // this hashtable is keyed on by a target namespace.  Its values
+    // this map is keyed on by a target namespace.  Its values
     // are Vectors containing namespaces imported by schema documents
     // with the key target namespace.
     // if an imprted schema has absent namespace, the value "null" is stored.
-    private Hashtable fImportMap = new Hashtable();
+    private Map<String, Vector> fImportMap = new HashMap();
     // all namespaces that imports other namespaces
     // if the importing schema has absent namespace, empty string is stored.
     // (because the key of a hashtable can't be null.)
     private Vector fAllTNSs = new Vector();
     // stores instance document mappings between namespaces and schema hints
-    private Hashtable fLocationPairs = null;
+    private Map fLocationPairs = null;
     
     //this hashtable is keyded on by DOM node objects. 
     //The table stores the hidden nodes
@@ -291,33 +282,33 @@
     // schema document.  This combination is used so that the user's
     // EntityResolver can provide a consistent way of identifying a
     // schema document that is included in multiple other schemas.
-    private Hashtable fTraversed = new Hashtable();
+    private Map fTraversed = new HashMap();
     
-    // this hashtable contains a mapping from Schema Element to its systemId
+    // this map contains a mapping from Schema Element to its systemId
     // this is useful to resolve a uri relative to the referring document
-    private Hashtable fDoc2SystemId = new Hashtable();
+    private Map fDoc2SystemId = new HashMap();
     
     // the primary XSDocumentInfo we were called to parse
     private XSDocumentInfo fRoot = null;
     
-    // This hashtable's job is to act as a link between the Schema Element and its
+    // This map's job is to act as a link between the Schema Element and its
     // XSDocumentInfo object.
-    private Hashtable fDoc2XSDocumentMap = new Hashtable();
+    private Map fDoc2XSDocumentMap = new HashMap();
     
     // map between <redefine> elements and the XSDocumentInfo
     // objects that correspond to the documents being redefined.
-    private Hashtable fRedefine2XSDMap = new Hashtable();
+    private Map fRedefine2XSDMap = null;
     
     // map between <redefine> elements and the namespace support
-    private Hashtable fRedefine2NSSupport = new Hashtable();
+    private Map fRedefine2NSSupport = null;
     
     // these objects store a mapping between the names of redefining
     // groups/attributeGroups and the groups/AttributeGroups which
     // they redefine by restriction (implicitly).  It is up to the
     // Group and AttributeGroup traversers to check these restrictions for
     // validity.
-    private Hashtable fRedefinedRestrictedAttributeGroupRegistry = new Hashtable();
-    private Hashtable fRedefinedRestrictedGroupRegistry = new Hashtable();
+    private Map fRedefinedRestrictedAttributeGroupRegistry = new HashMap();
+    private Map fRedefinedRestrictedGroupRegistry = new HashMap();
     
     // a variable storing whether the last schema document
     // processed (by getSchema) was a duplicate.
@@ -428,7 +419,7 @@
      * @throws IOException
      */
     public SchemaGrammar parseSchema(XMLInputSource is, XSDDescription desc,
-            Hashtable locationPairs)
+            Map locationPairs)
     throws IOException {
         fLocationPairs = locationPairs;
         fSchemaParser.resetNodePool();   
@@ -929,6 +920,7 @@
                 schemaHint = (String)includeAttrs[XSAttributeChecker.ATTIDX_SCHEMALOCATION];
                 // store the namespace decls of the redefine element
                 if (localName.equals(SchemaSymbols.ELT_REDEFINE)) {
+                    if (fRedefine2NSSupport == null) fRedefine2NSSupport = new HashMap();
                     fRedefine2NSSupport.put(child, new SchemaNamespaceSupport(currSchemaInfo.fNamespaceSupport));
                 }
                 
@@ -1018,6 +1010,7 @@
                     newSchemaInfo != null) {
                 // must record which schema we're redefining so that we can
                 // rename the right things later!
+                if (fRedefine2XSDMap == null) fRedefine2XSDMap = new HashMap();
                 fRedefine2XSDMap.put(child, newSchemaInfo);
             }
             if (newSchemaRoot != null) {
@@ -1052,7 +1045,7 @@
     // that implicit redefinitions of groups and attributeGroups can be handled).
     protected void buildGlobalNameRegistries() {
         
-
+        registryEmpty = false;
         // Starting with fRoot, we examine each child of the schema
         // element.  Skipping all imports and includes, we record the names
         // of all other global components (and children of <redefine>).  We
@@ -1228,7 +1221,7 @@
                 // includes and imports will not show up here!
                 if (DOMUtil.getLocalName(globalComp).equals(SchemaSymbols.ELT_REDEFINE)) {
                     // use the namespace decls for the redefine, instead of for the parent <schema>
-                    currSchemaDoc.backupNSSupport((SchemaNamespaceSupport)fRedefine2NSSupport.get(globalComp));
+                    currSchemaDoc.backupNSSupport((fRedefine2NSSupport!=null)?(SchemaNamespaceSupport)fRedefine2NSSupport.get(globalComp):null);
                     for (Element redefinedComp = DOMUtil.getFirstVisibleChildElement(globalComp, fHiddenNodes);
                     redefinedComp != null;
                     redefinedComp = DOMUtil.getNextVisibleSiblingElement(redefinedComp, fHiddenNodes)) {
@@ -1448,32 +1441,32 @@
             declToTraverse.uri+","+declToTraverse.localpart;
         switch (declType) {
         case ATTRIBUTE_TYPE :
-            decl = (Element)fUnparsedAttributeRegistry.get(declKey);
-            declDoc = (XSDocumentInfo)fUnparsedAttributeRegistrySub.get(declKey);
+            decl = getElementFromMap(fUnparsedAttributeRegistry, declKey);
+            declDoc = getDocInfoFromMap(fUnparsedAttributeRegistrySub, declKey);
             break;
         case ATTRIBUTEGROUP_TYPE :
-            decl = (Element)fUnparsedAttributeGroupRegistry.get(declKey);
-            declDoc = (XSDocumentInfo)fUnparsedAttributeGroupRegistrySub.get(declKey);
+            decl = getElementFromMap(fUnparsedAttributeGroupRegistry, declKey);
+            declDoc = getDocInfoFromMap(fUnparsedAttributeGroupRegistrySub, declKey);
             break;
         case ELEMENT_TYPE :
-            decl = (Element)fUnparsedElementRegistry.get(declKey);
-            declDoc = (XSDocumentInfo)fUnparsedElementRegistrySub.get(declKey);
+            decl = getElementFromMap(fUnparsedElementRegistry, declKey);
+            declDoc = getDocInfoFromMap(fUnparsedElementRegistrySub, declKey);
             break;
         case GROUP_TYPE :
-            decl = (Element)fUnparsedGroupRegistry.get(declKey);
-            declDoc = (XSDocumentInfo)fUnparsedGroupRegistrySub.get(declKey);
+            decl = getElementFromMap(fUnparsedGroupRegistry, declKey);
+            declDoc = getDocInfoFromMap(fUnparsedGroupRegistrySub, declKey);
             break;
         case IDENTITYCONSTRAINT_TYPE :
-            decl = (Element)fUnparsedIdentityConstraintRegistry.get(declKey);
-            declDoc = (XSDocumentInfo)fUnparsedIdentityConstraintRegistrySub.get(declKey);
+            decl = getElementFromMap(fUnparsedIdentityConstraintRegistry, declKey);
+            declDoc = getDocInfoFromMap(fUnparsedIdentityConstraintRegistrySub, declKey);
             break;
         case NOTATION_TYPE :
-            decl = (Element)fUnparsedNotationRegistry.get(declKey);
-            declDoc = (XSDocumentInfo)fUnparsedNotationRegistrySub.get(declKey);
+            decl = getElementFromMap(fUnparsedNotationRegistry, declKey);
+            declDoc = getDocInfoFromMap(fUnparsedNotationRegistrySub, declKey);
             break;
         case TYPEDECL_TYPE :
-            decl = (Element)fUnparsedTypeRegistry.get(declKey);
-            declDoc = (XSDocumentInfo)fUnparsedTypeRegistrySub.get(declKey);
+            decl = getElementFromMap(fUnparsedTypeRegistry, declKey);
+            declDoc = getDocInfoFromMap(fUnparsedTypeRegistrySub, declKey);
             break;
         default:
             reportSchemaError("Internal-Error", new Object [] {"XSDHandler asked to locate component of type " + declType + "; it does not recognize this type!"}, elmNode);
@@ -1514,7 +1507,7 @@
         // if the parent is <redefine> use the namespace delcs for it.
         Element parent = DOMUtil.getParent(decl);
         if (DOMUtil.getLocalName(parent).equals(SchemaSymbols.ELT_REDEFINE))
-            nsSupport = (SchemaNamespaceSupport)fRedefine2NSSupport.get(parent);
+            nsSupport = (fRedefine2NSSupport!=null)?(SchemaNamespaceSupport)fRedefine2NSSupport.get(parent):null;
         // back up the current SchemaNamespaceSupport, because we need to provide
         // a fresh one to the traverseGlobal methods.
         schemaWithDecl.backupNSSupport(nsSupport);
@@ -1621,11 +1614,11 @@
     
     // an accessor method.  Just makes sure callers
     // who want the Identity constraint registry vaguely know what they're about.
-    protected Hashtable getIDRegistry() {
+    protected Map getIDRegistry() {
         return fUnparsedIdentityConstraintRegistry;
     }
     // an accessor method.  
-    protected Hashtable getIDRegistry_sub() {
+    protected Map getIDRegistry_sub() {
         return fUnparsedIdentityConstraintRegistrySub;
     }
     
@@ -1886,6 +1879,7 @@
     // before traversing a schema's parse tree, need to reset all traversers and
     // clear all registries
     void prepareForTraverse() {
+        if (!registryEmpty) {
         fUnparsedAttributeRegistry.clear();
         fUnparsedAttributeGroupRegistry.clear();
         fUnparsedElementRegistry.clear();
@@ -1901,12 +1895,12 @@
         fUnparsedIdentityConstraintRegistrySub.clear();
         fUnparsedNotationRegistrySub.clear();
         fUnparsedTypeRegistrySub.clear();
+        }
         
-        fXSDocumentInfoRegistry.clear();
         fDependencyMap.clear();
         fDoc2XSDocumentMap.clear();
-        fRedefine2XSDMap.clear();
-        fRedefine2NSSupport.clear();
+        if (fRedefine2XSDMap != null) fRedefine2XSDMap.clear();
+        if (fRedefine2NSSupport != null) fRedefine2NSSupport.clear();
         fAllTNSs.removeAllElements();
         fImportMap.clear();
         fRoot = null;
@@ -2151,7 +2145,7 @@
      * or because we've found the thing we're redefining.
      */
     void checkForDuplicateNames(String qName,
-    		Hashtable registry, Hashtable registry_sub, Element currComp,
+    		Map<String,Element> registry, Map<String,XSDocumentInfo> registry_sub, Element currComp,
 			XSDocumentInfo currSchema) {
         Object objElem = null;
         // REVISIT:  when we add derivation checking, we'll have to make
@@ -2172,7 +2166,7 @@
             // (the parent of the colliding element is a redefine)
             boolean collidedWithRedefine = true;
             if ((DOMUtil.getLocalName((elemParent = DOMUtil.getParent(collidingElem))).equals(SchemaSymbols.ELT_REDEFINE))) {
-                redefinedSchema = (XSDocumentInfo)(fRedefine2XSDMap.get(elemParent));
+                redefinedSchema = (fRedefine2XSDMap != null)?(XSDocumentInfo) (fRedefine2XSDMap.get(elemParent)): null;
                 // case where we're a redefining element.
             }
             else if ((DOMUtil.getLocalName(DOMUtil.getParent(currComp)).equals(SchemaSymbols.ELT_REDEFINE))) {
@@ -2223,7 +2217,7 @@
                 reportSchemaError("sch-props-correct.2", new Object []{qName}, currComp);
             }
         }
-    } // checkForDuplicateNames(String, Hashtable, Element, XSDocumentInfo):void
+    } // checkForDuplicateNames(String, Map, Element, XSDocumentInfo):void
     
     // the purpose of this method is to take the component of the
     // specified type and rename references to itself so that they
@@ -2540,7 +2534,22 @@
         }
         return false;
     }
-    
+
+    private Element getElementFromMap(Map<String, Element> registry, String declKey) {
+        if (registry == null) return null;
+        return registry.get(declKey);
+    }
+
+    private XSDocumentInfo getDocInfoFromMap(Map<String, XSDocumentInfo> registry, String declKey) {
+        if (registry == null) return null;
+        return registry.get(declKey);
+    }
+
+    private Object getFromMap(Map registry, String key) {
+        if (registry == null) return null;
+        return registry.get(key);
+    }
+
     void reportSchemaFatalError(String key, Object[] args, Element ele) {
         reportSchemaErr(key, args, ele, XMLErrorReporter.SEVERITY_FATAL_ERROR);
     }