ModelAndView mav = new ModelAndView().addAllObjects(implicitModel);
if ("".equals(attrName)) {
Class resolvedType = GenericTypeResolver.resolveReturnType(handlerMethod, handlerType);
attrName = Conventions.getVariableNameForReturnType(handlerMethod, resolvedType, returnValue);
}
return mav.addObject(attrName, returnValue);
}
else {
throw new IllegalArgumentException("Invalid handler method return value: " + returnValue);
}
}