我对JUnit5和mockito框架完全陌生。现在我尝试为函数实现junit测试用例。有人能帮忙模拟一下吗，因为下面的测试实现在指定的行抛出一个nullpointerexception。

Class XYZ{

       @Autowired
       private SoapCall soapCall;

       public void validate(){

                 //code....

            JAXBElement <SubDTO> jax = (JAXBElement <Sub_DTO>) soapCall.callSoapService(val1, val2, val3, val4, val5);

            SubDTO  response = jax.getValue();  // Getting null pointer exception while Unit testing at this line   

        }
}

单元测试

Class TestValid{

   @Mock
   SoapCall soapCall;

   @InjectMocks
   XYZ xyzzy;

   @BeforeEach
   void setUp(){
      MockitoAnnotations.initMocks(this);
   }

   @Test
   public void test1(){
        SubDTO dto= new SubDTO("a","b","c");

        JAXBElement<SubDTO> jax = new JAXBElement <> (any(), any(), any());

        jax.setValue(dto)            

   Mockito.when(soapCall.callSoapService(any(),any(),any(),anyInt(),anyInt())).thenReturn( jax );

        Assertions.assertDoesNotThrow(()->xyz.validate());
   }
}