问题
I am aware of ResultBinding when trying to validate a form (get request), i am also aware of @Valid when trying to validate a request body but i have no knowledge of validating a multipartForm Request parameter. I have a multipart form with a request parameter @RequestParam("model") String userJson of a json string representation of my User.class. when i convert the json to an object,
User user = new Gson().fromJson(userJson, User.class);
how can i check if the parameters in the user class meets requirements, such as (email having an '@' or first name not having numeral values) ?
This is my code, the controller :
@RequestMapping(value = "/signup", method = RequestMethod.POST)
public ResponseEntity<ResponseModel> SignUp(@RequestParam("file") MultipartFile file, @RequestParam("model") String userJson, RedirectAttributes redirectAttributes){
User tempSavedUser = new User();
try {
if (file.isEmpty()) {
redirectAttributes.addFlashAttribute("message", "Please select a file to upload");
responseModel.setIsSuccessful(false).setResponseMessage("Please select an image to upload");
return new ResponseEntity<>(responseModel, HttpStatus.CREATED); // return response to client.
}
User user = new Gson().fromJson(userJson, User.class);
tempSavedUser = this.defaultUserDAOService.saveUser(user);
responseModel.setIsSuccessful(true);
responseModel.setResponseMessage("Registration was successful, Please check your mail for an account activation link");
return new ResponseEntity<ResponseModel>(responseModel, HttpStatus.CREATED);
}
this is the user class to:
@Table(name = "Users")
public class User extends DefaultEntity {
@Column(name = "FirstName")
@NotNull(message = "Enter a FirstName")
private String firstName;
@Column(name = "LastName")
@NotBlank(message = "Enter a LastName")
private String lastName;
@Column(unique = true,name = "UserName")
@NotBlank(message = "Enter a UserName")
private String userName;
@Column(unique = true, name = "Email")
@NotBlank(message = "Please enter an Email address")
@Email(message = "Enter a valid Email")
private String email;
@Column(name = "Password")
@NotBlank(message = "Enter a Password")
private String password;
@Enumerated(EnumType.STRING)
@Column(name = "Gender")
private Gender gender;
@Column(name = "Address")
@NotBlank(message = "Please enter your Home Address")
private String address;
@Column(name = "Country")
@NotBlank(message = "Please enter your Country")
private String country;
@Column(name = "Picture")
private String picture;
@Column(unique = true, name = "PhoneNumber") //make this accept only numbers
private String phoneNumber;
@Column(name = "Bio")
private String bio;
@Enumerated(EnumType.STRING)
@Column(name = "OnlineStatus")
private OnlineStatus onlineStatus;
@Enumerated(EnumType.STRING)
@Column(name = "UserType")
private UserType userType;
@Column(name = "Money")
private double money;
//@MapsId()
@OneToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinColumn(name = "playerstats")
private PlayerStats playerStats;
//columnDefinition = "tinyint default false"
@Column(name = "locked",columnDefinition = "BOOL default false")
private Boolean locked;
@Transient
private MultipartFile file;
public String getFirstName() {
return firstName;
}
public User setFirstName(String firstName) {
this.firstName = firstName;
return this;
}
public String getLastName() {
return lastName;
}
public User setLastName(String lastName) {
this.lastName = lastName;
return this;
}
public String getUserName() {
return userName;
}
public User setUserName(String userName) {
this.userName = userName;
return this;
}
public String getEmail() {
return email;
}
public User setEmail(String email) {
this.email = email;
return this;
}
public String getPassword() {
return password;
}
public User setPassword(String password) {
this.password = password;
return this;
}
public Enum.Gender getGender() {
return gender;
}
public User setGender(Enum.Gender gender) {
this.gender = gender;
return this;
}
public String getAddress() {
return address;
}
public User setAddress(String address) {
this.address = address;
return this;
}
public String getCountry() {
return country;
}
public User setCountry(String country) {
this.country = country;
return this;
}
public String getPicture() {
return picture;
}
public User setPicture(String picture) {
this.picture = picture;
return this;
}
public String getBio() {
return bio;
}
public User setBio(String bio) {
this.bio = bio;
return this;
}
public Enum.OnlineStatus getOnlineStatus() {
return onlineStatus;
}
public User setOnlineStatus(Enum.OnlineStatus onlineStatus) {
this.onlineStatus = onlineStatus;
return this;
}
public Enum.UserType getUserType() {
return userType;
}
public User setUserType(Enum.UserType userType) {
this.userType = userType;
return this;
}
public double getMoney() {
return money;
}
public User setMoney(double money) {
this.money = money;
return this;
}
public String getPhoneNumber() {
return phoneNumber;
}
public User setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
return this;
}
public MultipartFile getFile() {
return file;
}
public User setFile(MultipartFile file) {
this.file = file;
return this;
}
public PlayerStats getPlayerStats() {
return playerStats;
}
public User setPlayerStats(PlayerStats playerStats) {
this.playerStats = playerStats;
return this;
}
public Boolean getLocked() {
return locked;
}
public void setLocked(Boolean locked) {
this.locked = locked;
}
}
回答1:
Inorder to validate a multipart form with spring you can take take this approach :
1. Add Dependencies
- include the commons-fileupload which is used to upload a MultipartFile.
- include the validation-api to create a Validator.
As:
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.3.1</version>
</dependency>
<dependency>
<groupId>javax.validation</groupId>
<artifactId>validation-api</artifactId>
<version>1.1.0.Final</version>
</dependency>
2.Create a Web Config:
@EnableWebMvc
@Configuration
@ComponentScan(basePackages = {
"com.test"
})
public class WebConfig extends WebMvcConfigurerAdapter {
@Bean
public InternalResourceViewResolver viewResolver() {
InternalResourceViewResolver viewResolver = new InternalResourceViewResolver();
viewResolver.setViewClass(JstlView.class);
viewResolver.setPrefix("/WEB-INF/jsp/");
viewResolver.setSuffix(".jsp");
return viewResolver;
}
@Bean
public ResourceBundleMessageSource messageSource() {
ResourceBundleMessageSource rb = new ResourceBundleMessageSource();
rb.setBasenames(new String[] {
"validation"
});
return rb;
}
@Bean(name = "multipartResolver")
public CommonsMultipartResolver getResolver() {
CommonsMultipartResolver commonsMultipartResolver = new CommonsMultipartResolver();
//set max upload size per file is 20mb
commonsMultipartResolver.setMaxUploadSizePerFile(20 * 1024 * 1024);
return commonsMultipartResolver;
}
}
3.Create WebInitializer Class which extends from AbstractAnnotationConfigDispatcherServletInitializer
public class WebInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {
@Override
protected Class << ? > [] getRootConfigClasses() {
return new Class[] {
WebConfig.class
};
}
@Override
protected Class << ? > [] getServletConfigClasses() {
// TODO Auto-generated method stub
return null;
}
@Override
protected String[] getServletMappings() {
return new String[] {
"/"
};
}
}
4. Create Your Model
public class Model {
private User user;
private CommonsMultipartFile[] files;
//getter and setter
}
5.Create a Validator to validate you file
@Component
public class ModelValidator implements Validator {
public boolean supports(Class << ? > clazz) {
return Model.class.isAssignableFrom(clazz);
}
public void validate(Object target, Errors errors) {
Model model = (Model) target;
CommonsMultipartFile[] commonsMultipartFiles = model.getFiles();
for (CommonsMultipartFile multipartFile: commonsMultipartFiles) {
if (multipartFile.getSize() == 0) {
errors.rejectValue("files", "myapplication.missing.file");
}
}
}
}
6. Add validation error message in side application.properties under resources folder
myapplication.missing.file=No file choose
7. Develop a controller
@Controller
@RequestMapping(value = "/")
public class Controller {
@Autowired
ModelValidator modelValidator;
@RequestMapping(value = "/page", method = RequestMethod.GET)
public ModelAndView page() {
ModelAndView model = new ModelAndView("page");
model.addObject("model", new Model());
return model;
}
@RequestMapping(value = "/upload", method = RequestMethod.POST)
public ModelAndView upload(@ModelAttribute("model") Model model, BindingResult result) throws IOException {
// :::: VALIDATION HAPPENS HERE ::::
fileValidator.validate(model, result);
if (result.hasErrors()) {
return new ModelAndView("page");
}
return new ModelAndView("success", "fileNames", processUpload(model));
}
private List < String > processUpload(Model model) throws IOException {
List < String > Models = new ArrayList < String > ();
CommonsMultipartFile[] commonsMultipartFiles = model.getFiles();
for (CommonsMultipartFile multipartFile: commonsMultipartFiles) {
FileCopyUtils.copy(multipartFile.getBytes(), new File("C:\\upload\\" + multipartFile.getOriginalFilename()));
fileNames.add(multipartFile.getOriginalFilename());
}
return fileNames;
}
}
More Information:
https://memorynotfound.com/spring-mvc-file-upload-example-validator/ http://websystique.com/springmvc/spring-mvc-4-fileupload-download-hibernate-example/ http://javainsimpleway.com/spring-mvc-file-upload-with-validation/
来源：https://stackoverflow.com/questions/52152760/spring-boot-how-can-i-validate-a-multipart-form-in-springboot