Spring boot 向kafka使用者模拟对象时出现不必要的存根异常

我为kafka receiver编写了一个void方法，并尝试编写JUNIT，但它抛出了不必要的存根异常

 @Component
 public class KafkaReceiver {

    @KafkaListener(topics = "${kafka-receiver-topic}")
    public void receiveTopic(ConsumerRecord<?, ?> consumerRecord) throws 
    Exception {


       JSONObject kafka=new JSONObject(consumerRecord.value().toString());

       }
    }

   @ExtendWith(MockitoExtension.class)
   public class KafkaReceiverTest {


   @Test
   public void receiveTopicTest() throws Exception {
    KafkaReceiver producer = Mockito.mock(KafkaReceiver.class);


      JSONObject expected = new JSONObject(); 
                expected.put("value","value");    

      ConsumerRecord<?, ?> record = new ConsumerRecord<>("topic", 0, 123L, 
                                                           "key",expected); 
      JSONObject exp = new JSONObject(record.value().toString());


      doNothing().when(producer).receiveTopic(record);
      assertEquals(expected.get("value"), exp.get("value"));
     }
     }

@组件
公共级卡夫卡接收器{
@KafkaListener（topics=“${kafka receiver topic}”）
public void receiveTopic（ConsumerRecord ConsumerRecord）抛出
例外情况{
JSONObject kafka=新的JSONObject（consumerRecord.value（）.toString（））；
}
}

我在下面返回的JUNIT测试用例正在抛出存根异常

 @Component
 public class KafkaReceiver {

    @KafkaListener(topics = "${kafka-receiver-topic}")
    public void receiveTopic(ConsumerRecord<?, ?> consumerRecord) throws 
    Exception {


       JSONObject kafka=new JSONObject(consumerRecord.value().toString());

       }
    }

   @ExtendWith(MockitoExtension.class)
   public class KafkaReceiverTest {


   @Test
   public void receiveTopicTest() throws Exception {
    KafkaReceiver producer = Mockito.mock(KafkaReceiver.class);


      JSONObject expected = new JSONObject(); 
                expected.put("value","value");    

      ConsumerRecord<?, ?> record = new ConsumerRecord<>("topic", 0, 123L, 
                                                           "key",expected); 
      JSONObject exp = new JSONObject(record.value().toString());


      doNothing().when(producer).receiveTopic(record);
      assertEquals(expected.get("value"), exp.get("value"));
     }
     }

@ExtendWith（MockitoExtension.class）
公共类卡夫卡考试{
@试验
public void receiveTopicTest（）引发异常{
KafkaReceiver producer=Mockito.mock（KafkaReceiver.class）；
预期的JSONObject=新的JSONObject（）；
预期。卖出（“价值”、“价值”）；
ConsumerRecord记录=新的ConsumerRecord（“主题”），0，123L，
“关键”，预期）；
JSONObject exp=新的JSONObject（record.value（）.toString（））；
doNothing（）.when（制作人）.receiveTopic（记录）；
assertEquals（预期的.get（“值”）、exp.get（“值”）；
}
}