如何在 Spring 中使用验证器？我遇到了 500 错误

Question

-错误详情：

HTTPステータス 500 - Request processing failed; nested exception is java.lang.IllegalStateException: An Errors/BindingResult argument is expected to be immediately after the model attribute argument in the controller method signature: public java.lang.String

-验证器class:

public class loginvalidator implements Validator{

    //交換できるオブジェクトなのか
    @Override
    public boolean supports(Class<?> clazz) {
        return MemberModel.class.isAssignableFrom(clazz);
    }

    @Override
    public void validate(Object target, Errors errors) {

        ValidationUtils.rejectIfEmpty(errors, "id", "id.empty");
        ValidationUtils.rejectIfEmpty(errors, "password", "id.empty");

        MemberModel membermodel= (MemberModel)target;

        boolean patternCheck = Pattern.matches("^[a-zA-Z0-9]*$", membermodel.getPassword());
        if(membermodel.getPassword().length()>4||patternCheck){
            errors.rejectValue("password", "negativevalue");
        }
    }
}

-控制器class-方法：

@RequestMapping(value="loginaction", method=RequestMethod.POST)
public String loginaction(HttpServletRequest request, Model model,   BindingResult bindingResult, MemberModel mmodel){

    HttpSession session = request.getSession();
    System.out.println("loginaction★★★★★★★★★"+bindingResult);
    new loginvalidator().validate(mmodel, bindingResult);
    if(bindingResult.hasErrors()){
        return "redirect:/loginform?badpassword=true";
    }

    //로그인 로직 시행
    int no = Integer.parseInt(request.getParameter("no"));
    String password= request.getParameter("password");
    System.out.println("loginaction 진입 아이디:"+no+"   비번:   "+password);

    MemberModel membermodel = m.login(no);
    if(membermodel.getPassword().equals(password)){

        ArrayList<MemberModel> list=m.memberlist();
        System.out.println(list);
        session.setAttribute("loginflag", "true");
        session.setAttribute("name", membermodel.getName());
        session.setAttribute("no", membermodel.getNo());
        model.addAttribute("memberlist",list);

        return "memberlist";
    }else{
        return "redirect:/loginform?failflag=true";
    }
}

Answer 1

使用@Valid 注释标记您的模型参数

Answer 2

您面临的问题是模型属性参数需要在 BindingResult:

之前

@ModelAttribute("mmodel") MemberModel mmodel, BindingResult result

此外，在这种情况下不要使用 @Valid。

如何在 Spring 中使用验证器？我遇到了 500 错误

How do I use a validator in Spring? I encountered a 500 error

java

spring

spring-mvc

illegalstateexception