Load EMF model instance from XMI file

Question

I know there are several QnA about this subject. I have tried lots of solution, I am always getting same error.

My code structure is like:

Resource.Factory.Registry reg = Resource.Factory.Registry.INSTANCE;
    Map<String, Object> m = reg.getExtensionToFactoryMap();
    m.put("xmi", new XMIResourceFactoryImpl());

    ResourceSet resSet = new ResourceSetImpl();
    Resource resource = resSet.getResource(URI.createURI("model/List.xmi"), true);
    resource.load(Collections.EMPTY_MAP);
    EObject root = resource.getContents().get(0);

Error:

Exception in thread "main" org.eclipse.emf.ecore.resource.impl.ResourceSetImpl$1DiagnosticWrappedException: org.eclipse.emf.ecore.xmi.PackageNotFoundException: Package with uri 'List' not found. (file:///C:/Users/2/My%20Repository/UNIT%20Research%20and%20Development/com.unitbilisim.research.transformation/model/List.xmi, 6, 40) at org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.handleDemandLoadException(ResourceSetImpl.java:319) at org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoadHelper(ResourceSetImpl.java:278) at org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.getResource(ResourceSetImpl.java:406) at com.unitbilisim.research.transformation.ConvertEcore2Graph.main(ConvertEcore2Graph.java:61) Caused by: org.eclipse.emf.ecore.xmi.PackageNotFoundException: Package with uri 'List' not found. (file:///C:/Users/2/My%20Repository/UNIT%20Research%20and%20Development/com.unitbilisim.research.transformation/model/List.xmi, 6, 40) at org.eclipse.emf.ecore.xmi.impl.XMLHandler.getPackageForURI(XMLHandler.java:2625) at org.eclipse.emf.ecore.xmi.impl.XMLHandler.getFactoryForPrefix(XMLHandler.java:2458) at org.eclipse.emf.ecore.xmi.impl.XMLHandler.createObjectByType(XMLHandler.java:1335) at org.eclipse.emf.ecore.xmi.impl.XMLHandler.createTopObject(XMLHandler.java:1504) at org.eclipse.emf.ecore.xmi.impl.XMLHandler.processElement(XMLHandler.java:1026) at org.eclipse.emf.ecore.xmi.impl.XMIHandler.processElement(XMIHandler.java:77) at org.eclipse.emf.ecore.xmi.impl.XMLHandler.startElement(XMLHandler.java:1008) at org.eclipse.emf.ecore.xmi.impl.XMLHandler.startElement(XMLHandler.java:719) at org.eclipse.emf.ecore.xmi.impl.XMIHandler.startElement(XMIHandler.java:163) at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(Unknown Source) at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.startElement(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$ContentDriver.scanRootElementHook(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source) at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source) at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source) at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl.parse(Unknown Source) at org.eclipse.emf.ecore.xmi.impl.XMLLoadImpl.load(XMLLoadImpl.java:175) at org.eclipse.emf.ecore.xmi.impl.XMLResourceImpl.doLoad(XMLResourceImpl.java:261) at org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1518) at org.eclipse.emf.ecore.resource.impl.ResourceImpl.load(ResourceImpl.java:1297) at org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoad(ResourceSetImpl.java:259) at org.eclipse.emf.ecore.resource.impl.ResourceSetImpl.demandLoadHelper(ResourceSetImpl.java:274) ... 2 more

What does 'package with uri "" not found' mean ? Can I read xmi file directly or do I need to parse it as xml file ?

I have also tried this -> https://stackoverflow.com/a/4615965/1604503

    XMIResource resource = new XMIResourceImpl(URI.createURI("model/List.xmi"));
    resource.load(null);
    System.out.println( resource.getContents().get(0) );

PackageNotFoundEx. and Reource$IOWrappedEx. again :(

Please help

kind regards

Answer 1

The reason was, I did not generate the model codes. Because of that, 'List' package could not be found. I did add it to my packageRegistry and that's all.

        ResourceSet resourceSet = new ResourceSetImpl();

        // register UML
        Map packageRegistry = resourceSet.getPackageRegistry();
        packageRegistry.put(list.ListPackage.eNS_URI, list.ListPackage.eINSTANCE);

        // Register XML resource as UMLResource.Factory.Instance
        Map extensionFactoryMap = Resource.Factory.Registry.INSTANCE.getExtensionToFactoryMap();
        extensionFactoryMap.put("xmi", new XMIResourceFactoryImpl());

        Resource resource = (Resource) resourceSet.createResource(uri);


        // try to load the file into resource
        resource.load(null);

Answer 2

You should use URI.createFileURI(absolutePathUri) instead of URI.createURI(uri). Also, your model instance (in your case it is List.xmi file) must have xsi:schemaLocation attribute with relative path to your metamodel to avoid pre-registration of your metamodel package. Very important note: your uri parameter must be constructed from absolute path of your model

Kotlin language example:

    Resource.Factory.Registry.INSTANCE.extensionToFactoryMap.apply {
        put("ecore", EcoreResourceFactoryImpl())
        put("xmi", XMIResourceFactoryImpl())
    }

    val resourceSet = ResourceSetImpl()

    // createFileURI method is able to locate metamodel by xsi:schemaLocation
    // absolute path is important here !!!
    val resource = resourceSet.getResource(URI.createFileURI(File(modelPath).absolutePath), true)
    resource.allContents.forEach { eObj ->
        //do smth
    }

To make pre-registration of dynamic EPackage refer to eclipse wiki