private void validateUnique(
     Resource resource,
     ResourceElement<QNameSymbol, Composite> element,
     XMLStreamReader reader,
     IntrospectionContext context) {
   Contribution contribution = resource.getContribution();
   for (Resource entry : contribution.getResources()) {
     if (resource == entry) {
       // skip self since the resource is added to the contribution and will be iterated
       continue;
     }
     if (resource.getContentType().equals(entry.getContentType())) {
       for (ResourceElement<?, ?> elementEntry : entry.getResourceElements()) {
         if (element.getSymbol().equals(elementEntry.getSymbol())) {
           QName name = element.getSymbol().getKey();
           Location location = reader.getLocation();
           Composite composite = element.getValue();
           DuplicateComposite error =
               new DuplicateComposite(
                   "Duplicate composite found with name: " + name, location, composite);
           context.addError(error);
           break;
         }
       }
     }
   }
 }
 @SuppressWarnings({"unchecked"})
 public void process(Resource resource, IntrospectionContext context) {
   Source source = resource.getSource();
   ClassLoader classLoader = context.getClassLoader();
   URI contributionUri = context.getContributionUri();
   URL location = source.getBaseLocation();
   IntrospectionContext childContext =
       new DefaultIntrospectionContext(contributionUri, classLoader, location);
   Composite composite;
   try {
     // check to see if the resource has already been evaluated
     composite = loader.load(source, Composite.class, childContext);
   } catch (LoaderException e) {
     throw new Fabric3Exception(e);
   }
   if (composite == null) {
     // composite could not be parsed
     InvalidXmlArtifact error = new InvalidXmlArtifact("Invalid composite: " + location, null);
     context.addError(error);
     return;
   }
   boolean found = false;
   for (ResourceElement element : resource.getResourceElements()) {
     if (element.getSymbol().getKey().equals(composite.getName())) {
       element.setValue(composite);
       found = true;
       break;
     }
   }
   if (!found) {
     // should not happen
     String identifier = composite.getName().toString();
     throw new AssertionError("Resource element not found: " + identifier);
   }
   if (childContext.hasErrors()) {
     context.addErrors(childContext.getErrors());
   }
   if (childContext.hasWarnings()) {
     context.addWarnings(childContext.getWarnings());
   }
   resource.setState(ResourceState.PROCESSED);
 }