Comment 1 Nalini Ganapati 2011-03-14 14:29:26 EDT

Created attachment 191156 [details]
Test xsd to reproduce the problem

Comment 2 Ed Merks 2011-03-14 17:04:48 EDT

If you use this in your generated factory the element handler will work better

  public TestResourceFactoryImpl()
  {
    super();
    extendedMetaData = 
      new BasicExtendedMetaData(new EPackageRegistryImpl(EPackage.Registry.INSTANCE))
      {
        {
          extendedMetaDataHolderCache = new HashMap<EModelElement, Object>();
        }
      };

Please try it and let me know...

Comment 3 Nalini Ganapati 2011-03-14 17:34:13 EDT

Thanks. I just tried with the lines added to the TestResourceFactoryImpl constructor. The wizard created the filesystem as the intial model object, but the editor threw exceptions while loading -

org.eclipse.emf.ecore.xmi.PackageNotFoundException: Package with uri 'null' not found. (platform:/resource/p/My.test, 2, 14)
at org.eclipse.emf.ecore.xmi.impl.XMLHandler.createObjectByType(XMLHandler.java:1307)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.createTopObject(XMLHandler.java:1468)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.processElement(XMLHandler.java:1019)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.startElement(XMLHandler.java:1001)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.startElement(XMLHandler.java:712)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$ContentDriver.scanRootElementHook(Unknown Source)
...

and 

org.eclipse.emf.ecore.xmi.ClassNotFoundException: Class 'fileSystem' is not found or is abstract. (platform:/resource/p/My.test, 2, 14)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.validateCreateObjectFromFactory(XMLHandler.java:2244)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.validateCreateObjectFromFactory(XMLHandler.java:2235)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.createObjectByType(XMLHandler.java:1332)
	at org.eclipse.emf.ecore.xmi.impl.XMLHandler.createTopObject(XMLHandler.java:1468)
...

Comment 4 Ed Merks 2011-03-14 17:50:04 EDT

I tried the following in the generated example, so it looks to me like it properly saves and loads.  Your problem sounds like one of not using the generated resource factory.  Set a breakpoint in the resource factory to verify it's kicking in...

  public static void main(String[] args)
  {
    // Create a resource set to hold the resources.
    //
    ResourceSet resourceSet = new ResourceSetImpl();
    
    // Register the appropriate resource factory to handle all file extensions.
    //
    resourceSet.getResourceFactoryRegistry().getExtensionToFactoryMap().put
      (Resource.Factory.Registry.DEFAULT_EXTENSION, 
       new TestResourceFactoryImpl());

    // Register the package to ensure it is available during loading.
    //
    resourceSet.getPackageRegistry().put
      (TestPackage.eNS_URI, 
       TestPackage.eINSTANCE);
        
    // If there are no arguments, emit an appropriate usage message.
    //
    if (args.length == 0)
    {
      System.out.println("Enter a list of file paths or URIs that have content like this:");
      try
      {
        Resource resource = resourceSet.createResource(URI.createURI("http:///My.test"));
        DocumentRoot documentRoot = TestFactory.eINSTANCE.createDocumentRoot();
        FileSystem fileSystem = TestFactory.eINSTANCE.createFileSystem();
        Folder folder = TestFactory.eINSTANCE.createFolder();
        Test.File file = TestFactory.eINSTANCE.createFile();
        Folder subfolder = TestFactory.eINSTANCE.createFolder();
        documentRoot.setFileSystem(fileSystem);
        fileSystem.getFolders().add(folder);
        folder.getMembers().add(file);
        folder.getMembers().add(subfolder);
        resource.getContents().add(documentRoot);
        resource.save(System.out, null);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        resource.save(out, null);
        Resource resource2 = resourceSet.createResource(URI.createURI("http:///My2.test"));
        resource2.load(new ByteArrayInputStream(out.toByteArray()), null);
        resource2.save(System.out, null);
      }
      catch (IOException exception) 
      {
        exception.printStackTrace();
      }
    }

Comment 5 Nalini Ganapati 2011-03-14 18:17:02 EDT

Thanks Ed. I just tried again and noticed that I had mistakenly commented out extendedMetaData.putPackage(null, TestPackage.eINSTANCE) in the constructor for the resource factory. So, it now works, both the scenario I described in comment 3 and with your suggestion in comment 4.

Is there any documentation that describes the usage of extendedMetaDataHolderCache?

Comment 6 Ed Merks 2011-03-14 18:35:27 EDT

No, the BasicExtendedMeta has only the Javadoc.  I don't expect that you'd ever have figured out this was a good way to avoid the problem you were seeing. The problem is that ExtendedMetaData.INSTANCE returns different results from the local BasicExtendedMetaData instance. The local one has null in the registry by the global one doesn't (so the answer for getNamespace(EPackage) differs. But the caching is shared with the global instance.  It's a long story... Unfortunately there can be a great many separate packages all wanting to use the null namespace, so we have to do ugly things to support that...

Comment 7 Ed Merks 2011-03-19 00:10:40 EDT

I think this is a reasonable workaround for an issue doesn't come up frequently.