Refactored reflection throws null pointer when setting unassignable type on static field

The jdk.internal.reflect.MethodHandleObjectFieldAccessorImpl::set(Object, Object) method handles a class cast exception via:

    catch (ClassCastException e) {
      throw newSetIllegalArgumentException(obj.getClass());
    }

The target, obj can however be null if targeting a static field. In this case, a NullPointerException is thrown instead of the expected IllegalArgumentException.