如何在表单验证失败时提供我选择的消息


问题内容

我正在使用spring mvc 3.0。这是我的控制器类:

    @Controller
@RequestMapping("/author")
public class AuthorController {
    @Autowired
    private IAuthorDao authorDao;

    @InitBinder
    public void initBinder(WebDataBinder binder) {
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
        binder.registerCustomEditor(Date.class, new CustomDateEditor(
                dateFormat, true));
    }

    @RequestMapping(method = RequestMethod.GET)
    public String get(Model model) {
        return "author-list";
    }

    @RequestMapping(value = "/new", method = RequestMethod.GET)
    public String create(Model model) {
        model.addAttribute("author", new Author());
        return "author-form";
    }

    @RequestMapping(value = "/new", method = RequestMethod.POST)
    public String createPost(@ModelAttribute("author") Author author,
            BindingResult result) {
        new AuthorValidator().validate(author, result);
        if (result.hasErrors()) {
            return "author-form";
        } else {
            authorDao.persist(author);
            return "redirect:/author/" + author.getId();
        }
    }

    @RequestMapping(value = "/{authorId}", method = RequestMethod.GET)
    public String view(@PathVariable("authorId") int authorId) {
        return "author-view";
    }
}

我正在尝试验证作者对象。它具有dob attr,其类型为Date。

我正在使用以下类进行验证:

    public class AuthorValidator {
    public void validate(Author author, Errors errors) {

        if(author.getfName()==null)
            errors.rejectValue("fName", "required", "required");
        else if (!StringUtils.hasLength(author.getfName())) {
            errors.rejectValue("fName", "required", "required");
        }

        if(author.getfName()==null)
            errors.rejectValue("lName", "required", "required");
        else if (!StringUtils.hasLength(author.getlName())) {
            errors.rejectValue("lName", "required", "required");
        }

        if(author.getDob()==null)
            errors.rejectValue("dob", "required", "required");
        else if (!StringUtils.hasLength(author.getDob().toString())) {
            errors.rejectValue("dob", "required", "required");
        }
    }
}

当我不向表单输入任何内容时,它会提供所需的消息,这是正确的,但是当我给出错误的格式时,它将给出写Failed to convert property value of type java.lang.String to required type java.util.Date for property dob; nested exception is java.lang.IllegalArgumentException: Could not parse date: Unparseable date: "asdads" required操作的消息。如何使其像“无效日期”。

谢谢。


问题答案:

如果您使用标准的Spring设施,则需要做的是:

添加messageSource:

<bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">
    <property name="basename" value="com.example.messages" />
</bean>

添加com/example/messages.properties包含以下内容之一的属性文件:

typeMismatch.author.date = Invalid date
typeMismatch.date = Invalid date
typeMismatch.java.util.Date = Invalid date
typeMismatch = Invalid date

首先,您可以为特定date命令对象(author)中的特定字段()配置错误消息,其次- date任何命令对象中的特定字段,第三-
绑定java.util.Date类字段错误的消息,最后-错误的常规消息任何转换产生的结果。

这是我的JSP页面:

<%@ taglib uri="http://www.springframework.org/tags" prefix="s" %>
<%@ taglib uri="http://www.springframework.org/tags/form" prefix="sf" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
   <sf:form commandName="author">
      <sf:errors path="date"  /><br />
      <sf:input path="name"/><br />
      <sf:input path="date"/><br />
      <input type="submit" value="ok" />
   </sf:form>
</body>
</html>