有一个 Spring Boot 应用程序的复杂问题,我已经尝试解决了一段时间,我希望有人能帮助我。我已经删除了项目的所有其他部分,并试图使其尽可能简单。如果您转到 localhost:8080,将会出现一个带有两个文本框(用于输入两个名称)和一个提交按钮的表单。第一个姓名将存储在 Nominee 对象中,第二个姓名将存储在 Submitter 对象中。当您单击提交时,它将对字段执行验证以确保它们都不为空。我将在下面发布代码并在最后解释我的问题。
应用程序.java
@SpringBootApplication
@EnableJms
@EnableWebMvc
public class Application {
public static void main(String[] args) throws Exception {
// Launch the application
SpringApplication.run(Application.class, args);
}
}
WebController.java
@Controller
public class WebController extends WebMvcConfigurerAdapter {
protected static final Logger LOG = LoggerFactory.getLogger(WebController.class);
@InitBinder("nominee")
protected void initNomineeBinder(WebDataBinder binder) {
binder.setValidator(new NomineeValidator());
}
@InitBinder("submitter")
protected void initSubmitterBinder(WebDataBinder binder) {
binder.setValidator(new SubmitterValidator());
}
@Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addViewController("/success").setViewName("success");
}
@RequestMapping(value="/", method=RequestMethod.GET)
public String showForm(Model model) {
model.addAttribute("nominee", new Nominee());
model.addAttribute("submitter", new Submitter());
return "form";
}
@RequestMapping(value="/", method=RequestMethod.POST)
public String checkPersonInfo(@ModelAttribute(value="nominee") @Valid Nominee nominee,
@ModelAttribute(value="submitter") @Valid Submitter submitter,
BindingResult bindingResult, @Valid Model model) {
LOG.info("Nominee to string: " + nominee.toString());
LOG.info("Submitter to string: " + submitter.toString());
LOG.info("bindingResult to string: " + bindingResult.toString());
if (bindingResult.hasErrors()) {
return "form";
}
return "redirect:/success";
}
}
Nominee.java
import lombok.Data;
@Data
public class Nominee {
private String name;
}
NomineeValidatior.java
public class NomineeValidator implements Validator {
public boolean supports(Class clazz) {
return Nominee.class.equals(clazz);
}
public void validate(Object object, Errors errors) {
ValidationUtils.rejectIfEmpty(errors, "name", "name", "This field is empty.");
}
}
Submitter.java
import lombok.Data;
@Data
public class Submitter {
private String sname;
}
SubmitterValidator.java
public class SubmitterValidator implements Validator {
public boolean supports(Class clazz) {
return Submitter.class.equals(clazz);
}
public void validate(Object object, Errors errors) {
ValidationUtils.rejectIfEmpty(errors, "sname", "sname", "This field is empty.");
}
}
form.html
<html>
<body>
<form role="form" th:action="@{/}" method="post">
<h2>Nominee details</h2>
<table>
<tr>
<td>Name:</td>
<td>
<input type="text" th:field="${nominee.name}"/>
</td>
<td><p th:if="${#fields.hasErrors('nominee.name')}" th:errors="${nominee.name}">Empty field</p></td>
</tr>
</table>
<h2>Your details</h2>
<table>
<tr>
<td>Your name:</td>
<td>
<input type="text" th:field="${submitter.sname}"/>
</td>
<td><p th:if="${#fields.hasErrors('submitter.sname')}" th:errors="${submitter.sname}">Empty field</p></td>
</tr>
</table>
<div>
<button type="submit">Submit nomination</button>
</div>
</form>
</body>
</html>
成功.html
<html><body>Form successfully submitted.</body></html>
如果我将第一个文本字段留空(并填写或不填写第二个文本字段),屏幕上会显示一条错误消息:
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback. Tue May 12 13:10:17 AEST 2015 There was an unexpected error (type=Bad Request, status=400). Validation failed for object='nominee'. Error count: 1
我不知道如何修复它,以便将第一个文本框留空不会导致白色标签错误页面。如果我将第二个文本字段留空但填写第一个文本字段,它的行为完全正常,所以我不确定如果我以相反的方式尝试它为什么会导致错误。非常感谢任何解决此问题的帮助。
此外,您可能已经注意到我必须在 Nominee 和 Submitter 中使用 'name' 和 'sname' 作为我的变量,如果我将它们都设置为 'name' 那么它就不能正常工作。如果有任何方法可以编辑它以便他们都可以使用“名称”,我很想知道如何做。
编辑:找到解决方案。在 WebController 中,checkPersonInfo 需要为每个被验证的对象提供一个单独的 BindingResult。 BindingResult 需要紧跟在每个 @Valid 对象之后的方法参数中。
因此,在 WebController.java 中,这是:
@RequestMapping(value="/", method=RequestMethod.POST)
public String checkPersonInfo(@ModelAttribute(value="nominee") @Valid Nominee nominee,
@ModelAttribute(value="submitter") @Valid Submitter submitter,
BindingResult bindingResult, @Valid Model model) {
LOG.info("Nominee to string: " + nominee.toString());
LOG.info("Submitter to string: " + submitter.toString());
LOG.info("bindingResult to string: " + bindingResult.toString());
if (bindingResult.hasErrors()) {
return "form";
}
return "redirect:/success";
}
需要变成这样:
@RequestMapping(value="/", method=RequestMethod.POST)
public String checkPersonInfo(@ModelAttribute(value="nominee") @Valid Nominee nominee,
BindingResult bindingResultNominee,
@ModelAttribute(value="submitter") @Valid Submitter submitter,
BindingResult bindingResultSubmitter) {
LOG.info("Nominee to string: " + nominee.toString());
LOG.info("Submitter to string: " + submitter.toString());
if (bindingResultNominee.hasErrors() || bindingResultSubmitter.hasErrors()) {
return "form";
}
return "redirect:/success";
}
(模型对象已被删除,因为它实际上从未在任何地方使用过,如果您需要使用 @Valid 验证它,那么您将添加第三个 BindingResult 对象。)
最佳答案
找到解决方案。在 WebController 中,checkPersonInfo 需要为每个被验证的对象提供一个单独的 BindingResult。 BindingResult 需要紧跟在每个 @Valid 对象之后的方法参数中。
因此,在 WebController.java 中,这是:
@RequestMapping(value="/", method=RequestMethod.POST)
public String checkPersonInfo(@ModelAttribute(value="nominee") @Valid Nominee nominee,
@ModelAttribute(value="submitter") @Valid Submitter submitter,
BindingResult bindingResult, @Valid Model model) {
LOG.info("Nominee to string: " + nominee.toString());
LOG.info("Submitter to string: " + submitter.toString());
LOG.info("bindingResult to string: " + bindingResult.toString());
if (bindingResult.hasErrors()) {
return "form";
}
return "redirect:/success";
}
需要变成这样:
@RequestMapping(value="/", method=RequestMethod.POST)
public String checkPersonInfo(@ModelAttribute(value="nominee") @Valid Nominee nominee,
BindingResult bindingResultNominee,
@ModelAttribute(value="submitter") @Valid Submitter submitter,
BindingResult bindingResultSubmitter) {
LOG.info("Nominee to string: " + nominee.toString());
LOG.info("Submitter to string: " + submitter.toString());
if (bindingResultNominee.hasErrors() || bindingResultSubmitter.hasErrors()) {
return "form";
}
return "redirect:/success";
}
(模型对象已被删除,因为它实际上从未在任何地方使用过,如果您需要使用 @Valid 验证它,那么您将添加第三个 BindingResult 对象。)
关于java - 两个对象的 Spring 表单验证,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/30181245/