### Question:
DaprClientBuilder { public DaprClientBuilder withObjectSerializer(DaprObjectSerializer objectSerializer) { if (objectSerializer == null) { throw new IllegalArgumentException("Object serializer is required"); } if (objectSerializer.getContentType() == null || objectSerializer.getContentType().isEmpty()) { throw new IllegalArgumentException("Content Type should not be null or empty"); } this.objectSerializer = objectSerializer; return this; } DaprClientBuilder(); DaprClientBuilder withObjectSerializer(DaprObjectSerializer objectSerializer); DaprClientBuilder withStateSerializer(DaprObjectSerializer stateSerializer); DaprClient build();  }### Answer:
@Test(expected = IllegalArgumentException.class) public void noObjectSerializer() { new DaprClientBuilder().withObjectSerializer(null); }
@Test(expected = IllegalArgumentException.class) public void blankContentTypeInObjectSerializer() { new DaprClientBuilder().withObjectSerializer(mock(DaprObjectSerializer.class)); }