Question

我正在学习Spring验证。虽然它可能重复，但我不知道为什么会再次出现此错误。

我用很多例子检查了我的代码我的代码没问题，但它仍然给出了异常。我如何删除此异常。

错误是

Neither BindingResult nor plain target object for bean name 'validateform' available as request attribute

我的控制器

  @Controller
 public class HomeController {

private static final Logger logger = LoggerFactory.getLogger(HomeController.class);
@RequestMapping(value="/")
public String homepage(){
    return "home";  
}

@RequestMapping(value="login", method=RequestMethod.POST)
public String submitForm(@ModelAttribute("validateform") @Valid FormEntities validateform, BindingResult result, ModelMap model) {
    if(result.hasErrors()) {
        return "home";
    }

    model.addAttribute("message", "Successfully saved person: " + validateform.toString());
    return "home";
 }

}

Jsp Page

  <form:form action="login" commandName="validateform" method="post">
    <label for="nameInput">Name: </label>
    <form:input path="name"  placeholder="Name"/>
    <form:errors path="name" cssclass="error" />
    <br />

    <label for="ageInput">Age: </label>
    <form:input path="age" placeholder="Age" />
    <form:errors path="age" cssclass="error" />
    <br />

    <label for="phoneInput">Phone: </label>
    <form:input path="phone"  placeholder="Phone NO"/>
    <form:errors path="phone" cssclass="error" />
    <br />

    <label for="emailInput">Email: </label>
    <form:input path="email"  placeholder="Email "/>
    <form:errors path="email" cssclass="error" />
    <br />

    <label for="birthdayInput">Birthday: </label>
    <form:input path="birthday"  placeholder="MM/DD/YYYY" />
        <form:errors path="birthday" cssclass="error" />
        <br />

        <label for="genderOptions">Gender: </label>
        <form:select path="gender" >
            <form:option value="">Select Gender</form:option>
            <form:option value="MALE">Male</form:option>
            <form:option value="FEMALE">Female</form:option>
        </form:select>
        <form:errors path="gender" cssclass="error" />
        <br />

        <label for="newsletterCheckbox">Newsletter? </label>
        <form:checkbox path="receiveNewsletter" id="newsletterCheckbox" />
        <form:errors path="receiveNewsletter" cssclass="error"></form:errors>
        <br />
        <br />
        <input type="submit" value="Submit" />
</form:form>

弹簧context.xml中

    <annotation-driven />

<!-- Handles HTTP GET requests for /resources/** by efficiently serving up static resources in the ${webappRoot}/resources directory -->
<resources mapping="/resources/**" location="/resources/" />

<!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory -->
<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <beans:property name="prefix" value="/WEB-INF/views/" />
    <beans:property name="suffix" value=".jsp" />
</beans:bean>

<context:component-scan base-package="com.mine.formValidation" />

<beans:bean id="messageSource" class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
    <beans:property name="basename" value="/WEB-INF/messages"></beans:property>
</beans:bean>

实体类

   public class FormEntities {

@Size(min=5, max=30) 
private String name;

@NotEmpty @Email
private String email;

@NotNull @Min(13) @Max(110)
private Integer age;

@Size(min=11)
private String phone;

@NotNull
private Gender gender;

@DateTimeFormat(pattern="MM/dd/yyyy")
@NotNull @Past
private Date birthday;

private Boolean receiveNewsletter;

public enum Gender {
    MALE, FEMALE
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}

public Integer getAge() {
    return age;
}

public void setAge(Integer age) {
    this.age = age;
}

public String getPhone() {
    return phone;
}

public void setPhone(String phone) {
    this.phone = phone;
}

public Gender getGender() {
    return gender;
}

public void setGender(Gender gender) {
    this.gender = gender;
}

public Date getBirthday() {
    return birthday;
}

public void setBirthday(Date birthday) {
    this.birthday = birthday;
}

public Boolean getReceiveNewsletter() {
    return receiveNewsletter;
}

public void setReceiveNewsletter(Boolean receiveNewsletter) {
    this.receiveNewsletter = receiveNewsletter;
}

@Override
public String toString() {
    return "Subscriber [name=" + name + ", email=" + email + ", age=" + age
            + ", phone=" + phone + ", gender=" + gender + ", birthday="
            + birthday + ", receiveNewsletter=" + receiveNewsletter + "]";
}
}

Answer 1

当您使用form:form标记时，在呈现jsp页面时，命令对象必须已在请求中可用。

您可以使用@ModelAttribute方法和@SessionAttributes来缓解您的问题。通常，每次请求都会调用@ModelAttribute mehtod，但如果会话属性存储中已有model属性，则会从那里获取它。这适合您的场景，代码类似于

 @Controller
 @SessionAttributes("validateform")
 public class HomeController {

    // invoked only initially to create the FormEntities object
    @ModelAttribute("validateform")
    public FormEntities createFormEntities() {
        return new FormEntities();
    }
   ... // the rest of your controller
  }

使用Spring和Hibernate验证

1 个答案: