EMF提供了將定義好的metamodel serialize成XMI(XML Interchange)格式的功能。使用這個功能，可以將Object 序列化為XMI文檔。程式如下：(此範例程式使用了由My.ecore這個EMF meta model產生出來的model code。此處可下載emftest.zip(內含My.ecore)，下載後需再用EMF的工具，產生EMFTest這些package的Java code)
import EMFTest.EMFTestFactory;
import EMFTest.EMFTestPackage;
import EMFTest.vincent;
import EMFTest.impl.EMFTestPackageImpl;
public class TestData {
/**
* @param args
*/
public static void main(String[] args) {
//要先Initial PackageImpl，才能使用EMF的功能
EMFTestPackageImpl.init();
//Serialize時，所需的參數儲存於 saveOptions
Map<String, Object> saveOptions = new HashMap<String, Object>();
//啟用OPTION_EXTENDED_META_DATA後，才能指定要讓某個attribute Serialize為Element，而不是Attributes
saveOptions.put(XMLResource.OPTION_EXTENDED_META_DATA, Boolean.TRUE);
//設定vincent.company及vincent.location這2個attribute要serialize成Element
EMFTestPackage testPackage = EMFTestPackageImpl.eINSTANCE;
EAttribute companyAttr = testPackage.getvincent_Company();
EAttribute locationAttr = testPackage.getvincent_Location();
XMLMapImpl map = new XMLMapImpl();
XMLInfoImpl x = new XMLInfoImpl();
x.setXMLRepresentation(XMLInfoImpl.ELEMENT);
map.add(companyAttr, x);
map.add(locationAttr, x);
saveOptions.put(XMLResource.OPTION_XML_MAP, map);
saveOptions.put(XMLResource.OPTION_ENCODING, "UTF-8");
EMFTestFactory testFactory = EMFTestFactory.eINSTANCE;
vincent testElement = testFactory.createvincent();
testElement.setAge(32);
testElement.setCompany("IBM");
testElement.setLocation("Taipei");
ResourceSet resourceSet = new ResourceSetImpl();
// Register XML resource factory
resourceSet.getResourceFactoryRegistry().getExtensionToFactoryMap().put("xml", new XMLResourceFactoryImpl());
Resource resource = resourceSet.createResource(URI.createFileURI("Vincent.xml"));
// add the root object to the resource
resource.getContents().add(testElement);
// serialize resource – you can specify also serialization
// options which defined on org.eclipse.emf.ecore.xmi.XMIResource
try {
resource.save(saveOptions);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
上面的程式中，透過啟用OPTION_EXTENDED_META_DATA，使得可以設定那些EMF model的attribute要產生成XML的element。另一種做法為，直接在Ecore model的diagram中，增加Extended Meta Data，把要設定的Attribute設為element。如下圖
注意：這個方法要work，一樣要在serialize XML的程式中，加入
saveOptions.put(XMLResource.OPTION_EXTENDED_META_DATA, Boolean.TRUE);
參考資料：
