class ViewContentProvider implements IStructuredContentProvider,
			ITreeContentProvider {
		private TreeParent invisibleRoot;
		private IFConfigurationXMLInjectorImpl ifConfigXMLInjector;

		public void inputChanged(Viewer v, Object oldInput, Object newInput) {
		}

		public void dispose() {
		}

		public Object[] getElements(Object parent) {
			if (parent.equals(getViewSite())) {
				if (invisibleRoot == null)
					initialize();
				return getChildren(invisibleRoot);
			}
			return getChildren(parent);
		}

		public Object getParent(Object child) {
			if (child instanceof TreeObject) {
				return ((TreeObject) child).getParent();
			}
			return null;
		}

		public Object[] getChildren(Object parent) {
			if (parent instanceof TreeParent) {
				return ((TreeParent) parent).getChildren();
			}
			return new Object[0];
		}

		public boolean hasChildren(Object parent) {
			if (parent instanceof TreeParent)
				return ((TreeParent) parent).hasChildren();
			return false;
		}

		private void initialize() {
			// TODO: get the tree parent from emf model element of type
			// IFInstance
			ResourceSet resourceSet = new ResourceSetImpl();
			// Register the appropriate resource factory to handle all file
			// extensions.
			//
			resourceSet
					.getResourceFactoryRegistry()
					.getExtensionToFactoryMap()
					.put(Resource.Factory.Registry.DEFAULT_EXTENSION,
							new XMIResourceFactoryImpl());
			// Register the package to ensure it is available during loading.
			//
			Registry packageRegistry = resourceSet.getPackageRegistry();
			packageRegistry.put(IFConfigPackage.eNS_URI,
					IFConfigPackage.eINSTANCE);

			URI uri = URI
					.createFileURI("d:/workspaces/wp_irit_ifgui/fr.irit.ifclipse/src/fr/irit/ifclipse/xml/savedIFConfig2.ifconfig.xmi");
			Resource resource = resourceSet.createResource(uri);

			if (resource != null) {

				URI sourceXML = URI
						.createFileURI("d:/workspaces/wp_irit_ifgui/fr.irit.ifclipse/src/fr/irit/ifclipse/xml/step_1.xml");
				try {
					InputStream inputStrSourceXML = (new ExtensibleURIConverterImpl())
							.createInputStream(sourceXML);

					ifConfigXMLInjector = new IFConfigurationXMLInjectorImpl();

					resource = ifConfigXMLInjector.inject(inputStrSourceXML);
					
					resource.setURI(uri);
					resource.save(Collections.EMPTY_MAP);
					
				} catch (IOException e) {
					System.out.println("injection problem !");
					e.printStackTrace();
				}
	

				// 
				EList<EObject> contents = resource.getContents();
				EObject eObject = contents.get(0);
				if (eObject instanceof IFConfig)
					System.out.println("it's an IFConfig");

				IFConfig config = (IFConfig) eObject;

				TreeParent root = new TreeParent("Configuration: "
						+ config.getName());
				TreeParent p1 = new TreeParent("instances");
				root.addChild(p1);

				for (Instance instance : config.getInstances()) {
					p1.addChild(new TreeObject(instance.getPid().getName()));
				}

				invisibleRoot = new TreeParent("");
				invisibleRoot.addChild(root);

			}

		}
	}

<plugin>

   <extension point="org.eclipse.emf.ecore.generated_package">
      <package
            uri="http://irit.fr/ifconfiguration"
            class="fr.irit.ifclipse.metamodel.IFConfig.IFConfigPackage"
            genModel="src/fr/irit/ifclipse/metamodel/metamodel/IFConfiguration.genmodel"/>
   </extension>

</plugin>

<plugin>

   <extension point="org.eclipse.emf.ecore.generated_package">
      <package
            uri="http://irit.fr/ifconfiguration"
            class="fr.irit.ifclipse.metamodel.IFConfig.IFConfigPackage"
            genModel="src/fr/irit/ifclipse/metamodel/metamodel/IFConfiguration.genmodel"/>
   </extension>

</plugin>

	String eNS_URI = "http://irit.fr/ifconfiguration";