/* These two methods, createElementType and getElementType have to stay
     * synchronized, because they create an XmlObject and return the type
     * for that object, respectively. But since they do slightly different
     * things, they can't be refactored to share code, so exercise caution
     */
    public XmlObject createElementType(QName eltName, QName xsiType, SchemaTypeLoader wildcardTypeLoader)
    {
        SchemaType type = null;
        SchemaProperty prop = null;
        
        SchemaTypeLoader loader=XmlBeans.getContextTypeLoader();
        if (loader!=null){
        	SchemaGlobalElement element=loader.findElement(eltName);
        	if (element!=null){
        		type=element.getType();
        	}
        }
        
        if (type==null && (isSimpleType() || !containsElements() || isNoType()))
        {
            type = BuiltinSchemaTypeSystem.ST_NO_TYPE;
        }
        else
        {
            prop = (SchemaProperty)_propertyModelByElementName.get(eltName);
            if (prop != null)
            {
                type = prop.getType();
            }
            else if (_typedWildcardElements.contains(eltName) ||
                     _validSubstitutions.contains(eltName) || type!=null)
            {
                SchemaGlobalElement elt = wildcardTypeLoader.findElement(eltName);
                if (elt != null)
                {
                    type = elt.getType();
                    SchemaType docType = wildcardTypeLoader.findDocumentType(eltName);
                    if (docType != null)
                        prop = docType.getElementProperty(eltName);
                }
                else
                    type = BuiltinSchemaTypeSystem.ST_NO_TYPE;
            }
            else
            {
                // Check if the requested element isn't by any chance part of a
                // substitution group headed by one of the declared elements
                // Better not enable this yet
                /*
                SchemaGlobalElement elt = wildcardTypeLoader.findElement(eltName);
                SchemaGlobalElement sghead = elt == null ? null : elt.substitutionGroup();
                while (sghead != null)
                {
                    if (_propertyModelByElementName.containsKey(sghead.getName()))
                    {
                        type = elt.getType();
                        SchemaType docType = wildcardTypeLoader.findDocumentType(elt.getName());
                        if (docType != null)
                            prop = docType.getElementProperty(elt.getName());
                        break;
                    }
                    sghead = sghead.substitutionGroup();
                }
                */
                if (type == null)
                    type = BuiltinSchemaTypeSystem.ST_NO_TYPE;
            }

            if (xsiType != null)
            {
                SchemaType itype = wildcardTypeLoader.findType(xsiType);

                // NOTE: a previous version of XMLBeans used ST_NO_TYPE if the
                // xsiType was not derived from 'type', but this results in a
                // ClassCastException.  Instead we ignore xsi:type if it's not
                // found or a derived type.
                if (itype != null && type.isAssignableFrom(itype)) {
                    type = itype;
                }
            }
        }

        if (type != null)
            return ((SchemaTypeImpl)type).createUnattachedNode(prop);
        return null;
    }