如何在 Spring 中使用 Mock 为 CommonsMultipartFile 编写单元测试

Question

我正在使用 spring 3.0 org.springframework.web.multipart.commons.CommonsMultipartFile 进行文件上传。我想写下使用 Mockito 上传文件的单元测试用例。

以下是我的控制器类

private RegistrationService registrationService;

@RequestMapping(method = RequestMethod.POST)
    public String create(Registration registration, BindingResult result,ModelMap model)
            throws NumberFormatException, Exception {
        
        File uploadedFile = uploadFile(registration);
        List<Registration> userDetails = new ArrayList<Registration>();
        processUploadedFile(uploadedFile,userDetails);
        
        model.addAttribute("userDetails", userDetails);
        
        return "Registration";
    }
    
    private File uploadFile(Registration registration) {
        
        Date dt = new Date();
        SimpleDateFormat format = new SimpleDateFormat("MM_dd_yyyy_HH_mm_ss");
        File uploadedFile = new File(uploadFileLocation
                + registration.getFileData().getOriginalFilename() + "."
                + format.format(dt));
         
        try {
            registration.getFileData().transferTo(uploadedFile);
            
        } catch (IllegalStateException e) {
            logger.error("Error occurred while uploading file", e);  
        } catch (IOException e) {
            logger.error("Error occurred while uploading file", e);
        }   
        
        return uploadedFile;
    }

    private void processUploadedFile(File uploadedFile, List<Registration> userDetails)
            throws NumberFormatException, Exception {

        registrationService.processFile(uploadedFile, userDetails);
    }

注册类

public class Registration {
    private String name;
    private CommonsMultipartFile fileData;
    
    
    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public CommonsMultipartFile getFileData() {
        return fileData;
    }

    public void setFileData(CommonsMultipartFile fileData) {
        this.fileData = fileData;
    }
}

我的服务类方法

public void processFile(File uploadedFile,
            List<Registration> userDetails) throws NumberFormatException,
            Exception {     

        String record = "";

        try {

            FileWriter fstream = new FileWriter(outputFileLocation
                    + uploadedFile.getName());
            BufferedWriter out = new BufferedWriter(fstream);

            BufferedReader br = new BufferedReader(new FileReader(
                    uploadedFile.getAbsolutePath()));

            while ((record = br.readLine()) != null) {
                String[] requesterUser = record.split(",");

                if (insertUserToDB(requesterUser, userDetails) > 0)
                    out.write(record + ", Yes");
                else
                    out.write(record + ", No");

                out.newLine();

            }
            out.flush();
            out.close();

        } catch (FileNotFoundException e) {
            logger.error("Error occured while processing file",  e);
        } catch (IOException e) {
            
            logger.error("Error occured while processing file",  e);
        }

        
    }

如何对其进行单元测试？我是 Mockito 的新手。

编辑

我已经写下了测试上述代码的测试方法，但它为 multipartFile 返回 null。我应该如何测试上面的服务类 processFile 方法？

@Test
       public void testProcessFile() {
        private static final String TEST_FILE = "c:\\user.csv";
        MockMultipartHttpServletRequest request = new MockMultipartHttpServletRequest();
        MockMultipartHttpServletRequest mockMultipartHttpServletRequest = (MockMultipartHttpServletRequest)request;
        MultipartFile multipartFile = (MultipartFile) mockMultipartHttpServletRequest.getFile(TEST_FILE);

        Registration registration=new Registration();
        registration.setFileData(multipartFile);
        RegistrationService.processFile(uploadedFile, userDetails);
        }

我是 JUnit 和 mockito 的新手。非常感谢任何帮助或指针。

Answer 1

您可能需要考虑使用 Spring 的 Mock 实现 (org.springframework.mock.web.MockMultipartFile) 而不是使用 Mockito 创建一个模拟。

Answer 2

Heinrich Filter 是对的，但您还需要将字段fileData 的类型从CommonsMulitPartFile 更改为org.springframework.web.multipart.MultipartFile。 （这是CommonsMulitPartFile和MockMultipartFile上面的超级接口。

如果你已经这样做了，那么你可以使用 spring 提供的模拟对象创建多部分文件本身的模拟

MockMultipartFile mockMultipartFile = new MockMultipartFile(
    "fileData",
    fileName,
    "text/plain",
    content);