return new InterfaceDefaultMethodFailsToCheckNull() {};
    }

    default void doNotCheckNull(String unused) {}
  }

  private interface InterfaceDefaultMethodChecksNull {
    static InterfaceDefaultMethodChecksNull create() {
      return new InterfaceDefaultMethodChecksNull() {};
    }

    default void checksNull(String s) {
      checkNotNull(s);
    }
  }

  public void testInterfaceStaticMethod() {