code: private Object createDefaultResource(String className, ResourceInfo resourceRefInfo) throws Exception {
          if (className != null) {
              String javaCompDefaultFilter = "(" + com.ibm.ws.resource.ResourceFactory.JAVA_COMP_DEFAULT_NAME + "=*)";
              String createsFilter = FilterUtils.createPropertyFilter(ResourceFactory.CREATES_OBJECT_CLASS, className);
              String filter = "(&" + javaCompDefaultFilter + createsFilter + ")";
              return createResourceWithFilter(filter, resourceRefInfo);
          }
          return null;
      }
docs: Try to obtain an object instance by creating a resource using a
  ResourceFactory for a default resource.