### Question:
IdobataBuilder { public Idobata build() { if (requestInterceptor == null) { throw new IllegalArgumentException("RequestInterceptor may not be null."); } ensureDefaults(); return new IdobataImpl(client, requestInterceptor, converter, pusherBuilder); }  IdobataBuilder setClient(Client client); IdobataBuilder setRequestInterceptor(RequestInterceptor requestInterceptor); IdobataBuilder setConverter(Converter converter); IdobataBuilder setPusherBuilder(PusherBuilder pusherBuilder); Idobata build();  }### Answer:
@Test(expected = IllegalArgumentException.class) public void nullRequestInterceptorThrowsIllegalArgumentException() throws Exception { new IdobataBuilder().build(); }