Spring MVC：如何绑定到@ModelAttribute中的嵌套对象属性

Question

I have a unit test to carry out based on the following part of code:

  @RequestMapping(value = "/changePass", method = RequestMethod.POST)
  public ModelAndView changePass(@ModelAttribute(TAPPLICATION) AppBean applicationBean, BindingResult result, ModelMap model, Principal principal, HttpServletRequest request) throws NSException, SQLException {
         // ...

         if (applicationBean != null
                    && applicationBean.getChangePassDto() != null
                    && StringUtils.isNotEmpty(applicationBean.getChangePassDto().getNewPassword())) {

                String newPassword = applicationBean.getChangePassDto().getNewPassword();
                // ...                   
            }
            // ...

The AppBean contains the following getter and setter:

private ChangePassDto changePassDto;   

   public ChangePassDto getChangePassDto() {
        return changePassDto;
    }

    public void setChangePassDto(ChangePasswordDto changePassDto) {
        this.changePassDto = changePassDto;
    }

Basically when I execute the unit test the method applicationBean.getChangePassDto() is null but applicationBean is not null. How can I initialise the applicationBean.getChangePassDto() so that it does not return null ? I have initialised the other non object parameters with the .param method as it can be seen in my unit test.

I am also using Powermock as unit test framework.

Please find below part of my unit test:

    @Before
    public void setup() {

        request = new MockHttpServletRequest();
        request.setAttribute(DispatcherServlet.OUTPUT_FLASH_MAP_ATTRIBUTE, new FlashMap());
        response = new MockHttpServletResponse();
        session = new MockHttpSession();
        request.setSession(session);
        RequestContextHolder.setRequestAttributes(new ServletRequestAttributes(request));

        //Added viewResolver to prevent circular view path error
        InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
        viewResolver.setPrefix("/WEB-INF/jsp/");
        viewResolver.setSuffix(".jsp");

        this.mockMvc = MockMvcBuilders.standaloneSetup(appController).setViewResolvers(viewResolver).build();    
    }

    @Test
    public void changePass_ExpectC() throws Exception {

        PowerMockito.doNothing().when(passwordVal).validate(any(User.class), anyListOf(Params.class), any(Object.class),any(Errors.class));


        mockMvc.perform(post("/changePass").param("userLogName", "JOHN").param("userLogged", "userLogged").param("password", "password123").param("newPassword", "newPassword123").param("confirmNewPassword", "newPassword123"))
                 .andExpect(view().name(Constants.DENIED))
                .andExpect(status().isOk()
                 );
    }

Any idea how I can intitialise applicationBean.getchangePassDto() so that it is not null?

Thanks in advance for help.

Answer 1

Simply create a new instance of ChangePassDto in your AppBean :

public class AppBean {

  private ChangePassDto changePassDto = new ChangePassDto();

  public ChangePassDto getChangePassDto() {
    return changePassDto;
  }

  public void setChangePassDto(ChangePasswordDto changePassDto) {
    this.changePassDto = changePassDto;
  }

  // ...
}

You then need to use the full path to the properties in the nested DTO like this:

mockMvc.perform(post("/changePass")
    .param("changePassDto.userLogName", "JOHN")
    .param("changePassDto.userLogged", "userLogged")
    .param("changePassDto.password", "password123")
    .param("changePassDto.newPassword", "newPassword123")
    .param("changePassDto.confirmNewPassword", "newPassword123"))
.andExpect(view().name(Constants.DENIED))
.andExpect(status().isOk());