//Exercise 6 builds from Exercise 5
Lab5 lab5 = new Lab5();
XSDSchema schema = lab5.createSchema(xsdFile);

/**
 * Create global attributeGroup with name="shapeAttributes" and has the following
 * attributes:
 *   <attributeGroup name="shapeAttributes" />
 *     <attribute name="size" type="string" use="required" />
 *     <attribute name="length" type="int" use="optional" />
 *   </attributeGroup>
 */
XSDAttributeGroupDefinition shapeAttributes = XSDFactory.eINSTANCE.createXSDAttributeGroupDefinition();

//Set the name = "shapeAttributes"
shapeAttributes.setName("shapeAttributes");
                
/**
 * Create local attribute size, which need XSDAttributeUse to store the usage
 */
XSDAttributeUse sizeAttrUse = XSDFactory.eINSTANCE.createXSDAttributeUse();

//Set the use="required"
sizeAttrUse.setUse(XSDAttributeUseCategory.REQUIRED_LITERAL);

XSDAttributeDeclaration sizeAttr = XSDFactory.eINSTANCE.createXSDAttributeDeclaration();

//Set the name="size"
sizeAttr.setName("size");

//Set the type="string"
XSDSimpleTypeDefinition stringType = schema.getSchemaForSchema().
        resolveSimpleTypeDefinition(XSDConstants.SCHEMA_FOR_SCHEMA_URI_2001,"string");
sizeAttr.setTypeDefinition(stringType);

//Add the sizeAttr to the sizeAttrUse
sizeAttrUse.setContent(sizeAttr);

//Add the sizeAttrUse to the global attribute group
shapeAttributes.getContents().add(sizeAttrUse);

/**
 * Create local attribute length, which need XSDAttributeUse to store the usage
 */
XSDAttributeUse lengthAttrUse = XSDFactory.eINSTANCE.createXSDAttributeUse();

//Set the use="optional"
sizeAttrUse.setUse(XSDAttributeUseCategory.OPTIONAL_LITERAL);

XSDAttributeDeclaration lengthAttr = XSDFactory.eINSTANCE.createXSDAttributeDeclaration();

//Set the name="length"
lengthAttr.setName("length");

//Set the type="int"
XSDSimpleTypeDefinition intType = schema.getSchemaForSchema().
        resolveSimpleTypeDefinition(XSDConstants.SCHEMA_FOR_SCHEMA_URI_2001,"int");
lengthAttr.setTypeDefinition(intType);

//Add the lengthAttr to the lengthAttrUse
lengthAttrUse.setContent(lengthAttr);

//Add the lengthAttrUse to the global attribute group
shapeAttributes.getContents().add(lengthAttrUse);       

//Add the new attribute group to the root schema
schema.getContents().add(shapeAttributes);
                
/**
 * Now lets create and add some attributes to the given complexType
 *
 * <attribute name="lang" type="string" > 
 *
 * <complexType name="PurchaseOrderType" >
 *   <sequence>
 *     <element name="state" type="po:USState" minOccurs="0" />
 *     <element ref="po:notes" />
 *   </sequence>
 *   <attribute name="color" type="string" />
 *   <attribute ref="po:lang" />
 *   <attributeGroup ref="po:shapeAttributes" />
 * </complexType>
 *
 * Create Global Attribute name="lang" and type="string"
 * Create the local attribute color type="string"
 * Create then attribute reference to global attribute po:lang
 * Create attributeGroup reference to global attributeGroup po:shapeAttributes
 */

//Create Global Attribute name="lang" and type="string"
XSDAttributeDeclaration langAttr = XSDFactory.eINSTANCE.createXSDAttributeDeclaration();

//Set name="lang"
langAttr.setName("lang");

//Set type="string"
langAttr.setTypeDefinition(stringType);

//Add the global attribute to the given schema
schema.getContents().add(langAttr);

//Lets get the PurchaseOrderType complex type
XSDComplexTypeDefinition purchaseOrderType = schema.resolveComplexTypeDefinition("PurchaseOrderType");

//Create the local attribute color type="string"
XSDAttributeUse colorAttrUse = XSDFactory.eINSTANCE.createXSDAttributeUse();
                
XSDAttributeDeclaration colorAttr = XSDFactory.eINSTANCE.createXSDAttributeDeclaration();

//Set the name="color"
colorAttr.setName("color");

//Set type="string"             
colorAttr.setTypeDefinition(stringType);

//Add the colorAttr to the colorAttrUse
colorAttrUse.setContent(colorAttr);

//Add the colorAttrUse to the complex type
purchaseOrderType.getAttributeContents().add(colorAttrUse);

//Create then attribute reference to global attribute po:lang
XSDAttributeUse langRefAttrUse = XSDFactory.eINSTANCE.createXSDAttributeUse();
                
XSDAttributeDeclaration langRefAttr = XSDFactory.eINSTANCE.createXSDAttributeDeclaration();

//Set the reference="po:lang"
langRefAttr.setResolvedAttributeDeclaration(langAttr);
                
//Add the langRefAttr to the langRefAttrUse
langRefAttrUse.setContent(langRefAttr);

//Add the langRefAttrUse to the complex type
purchaseOrderType.getAttributeContents().add(langRefAttrUse);   

//Create attributeGroup reference to global attributeGroup po:shapeAttributes   
XSDAttributeGroupDefinition shapeAttributesRef = XSDFactory.eINSTANCE.createXSDAttributeGroupDefinition();
                
//Set the resolved attributeGroup
shapeAttributesRef.setResolvedAttributeGroupDefinition(shapeAttributes);

//Add the attribute group reference to the complex type
purchaseOrderType.getAttributeContents().add(shapeAttributesRef);

// Save the contents of the resource to the file system.
schema.eResource().save(Collections.EMPTY_MAP);