<?xml version="1.0" encoding="utf-8" ?>
<!--
/*   Copyright 2004 The Apache Software Foundation
 *
 *   Licensed 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.
 */
-->


<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">


    <!-- elements -->
    <xsd:element name="TestRootElem">
        <xsd:complexType>
            <xsd:sequence>
                <xsd:element ref="SubGrpHeadElem" maxOccurs="unbounded" />
                <xsd:element ref="ModelGrpTypeElem" minOccurs="1"/>
                <xsd:element ref="AttrGrpTypeElem" minOccurs="1" />
            </xsd:sequence>
        </xsd:complexType>
    </xsd:element>

    <xsd:element name="SubGrpHeadElem" type="SubGrpHeadElemType" />
    <xsd:element name="SubGrpHeadElem2" type="SubGrpHeadElemType2" />
    <xsd:element name="SubGrpMemberElem1" substitutionGroup="SubGrpHeadElem" />
    <xsd:element name="SubGrpMemberElem2" type="ExtensionSubGrpHeadElemType" substitutionGroup="SubGrpHeadElem"/>

    <xsd:element name="ModelGrpTypeElem" type="ModelGrpType" />
    <xsd:element name="AttrGrpTypeElem"  type="AttrGrpType" />


    <!-- types -->

    <xsd:complexType name="SubGrpHeadElemType">
        <xsd:sequence>
            <xsd:element name="SubGrpInnerElem1" type="xsd:string" />
            <xsd:element name="SubGrpInnerElem2" type="xsd:integer" />
        </xsd:sequence>
        <xsd:attribute name="SubGrpHeadAttr1" type="xsd:string" use="required" />
    </xsd:complexType>

    <xsd:complexType name="ExtensionSubGrpHeadElemType">
        <xsd:complexContent>
            <xsd:extension base="SubGrpHeadElemType">
                <xsd:sequence>
                    <xsd:element name="SubGrpInnerElem3" type="xsd:string"  />
                </xsd:sequence>
            </xsd:extension>
        </xsd:complexContent>
    </xsd:complexType>

    <xsd:complexType name="SubGrpHeadElemType2">
        <xsd:sequence>
            <xsd:element name="SubGrpInnerElem3" type="xsd:token" />
        </xsd:sequence>
        <xsd:attribute name="SubGrpHeadAttr1" type="xsd:string" use="required" />
    </xsd:complexType>


    <!-- reusable group definitions here -->
    <!-- Named Model Groups -->
    <xsd:group name="NamedModelGroup">
        <xsd:sequence>
            <xsd:element name="ModelGrpElem1" type="xsd:string" />
            <xsd:element name="ModelGrpElem2" type="xsd:string" minOccurs="1" />
        </xsd:sequence>
    </xsd:group>

    <xsd:group name="NamedModelGroup2">
        <xsd:sequence>
            <xsd:element name="ModelGrpElem3" type="xsd:string" />
            <xsd:element name="ModelGrpElem4" type="xsd:string" minOccurs="1" />
        </xsd:sequence>
    </xsd:group>

    <xsd:complexType name="ModelGrpType">
        <xsd:sequence>
            <xsd:group ref="NamedModelGroup" minOccurs="1" />
            <xsd:element name="ModelGrpTypeSubElem1" type="xsd:string" />
        </xsd:sequence>
    </xsd:complexType>

    <!-- attribute groups -->
    <xsd:attributeGroup name="AttributeGroup">
        <xsd:attribute name="AttrGrpAttribute1" type="xsd:string" use="required"/>
        <xsd:attribute name="AttrGrpAttribute2" type="xsd:string" use="required"/>
    </xsd:attributeGroup>

    <xsd:attributeGroup name="AttributeGroup2">
        <xsd:attribute name="AttrGrpAttribute3" type="xsd:string" use="required"/>
        <xsd:attribute name="AttrGrpAttribute4" type="xsd:string" use="required"/>
    </xsd:attributeGroup>

    <xsd:complexType name="AttrGrpType">
        <xsd:sequence>
            <xsd:element name="AttrGrpTypeSubElem1" type="xsd:string" />
        </xsd:sequence>
        <xsd:attributeGroup ref="AttributeGroup"/>
        <xsd:attribute name="AttrGrpTypeAttr1" type="xsd:string" use="required" />
    </xsd:complexType>


</xsd:schema>
