void packagePrivateOneArg(String s) {
      checkNotNull(s);
    }

    @Keep
    protected void protectedOneArg(String s) {
      checkNotNull(s);
    }

    @Keep
    public void oneNullableArg(@Nullable String s) {}

    @Keep
    public void oneNullableArgThrows(@Nullable String s) {
      doThrow(s);
    }

    @Keep
    public void twoArg(String s, Integer i) {
      checkNotNull(s);