Spring-MVC form validation highlight input field after DAO validation

Question

I'm converting Struts 1.3 project to Spring. Instead of struts form fields, I'm using spring form.

I have used ActionErrors in struts to highlight the field using errorStyleClass attribute.

Similarly, in spring cssErrorClass is available. But, How to use it after the dao validation?

@RequestMapping(value = "/login", method = RequestMethod.POST)
public String login(@ModelAttribute("login") @Validated Login login, BindingResult result, Model model) {

    if (result.hasErrors()) {

        //THIS VALIDATION DONE BY ANNOTATION AND HIGHLIGHTING THE FIELD
        //USING "cssErrorClass"

        return HOMEPAGE;
    }

    boolean checkAuthentication = authService.checkAuthentication(login);

    if(!checkAuthentication){

        // HOW TO SET THE ERROR HERE?

        // Is there any way to set the error like

        // error.setMessage("userId","invalid.data");

        // so that, is it possible to display error message by 
        // highlighting the fields using "cssErrorClass"?

    }


    return HOMEPAGE;
}

Answer 1

You need to annotate your entities using Java Bean Validation framework JSR 303 , like this

public class Model{
  @NotEmpty
  String filed1;

  @Range(min = 1, max = 150)
  int filed2;

  ....
}

And add @Valid to your controller, like this

public class MyController {

public String controllerMethod(@Valid Customer customer, BindingResult result) {
    if (result.hasErrors()) {
        // process error
    } else {
        // process without errors
    }
}

You can find more examples for it here and here

EDIT:

If you want to register more errors based on custom validation steps in code, you can use rejectValue() method in the BindingResult instance, like this:

bindingResult.rejectValue("usernameField", "error code", "Not Found username message");