首页 > 解决方案 > Spring 注解 @NotNull 和 @Size 不起作用

问题描述

我创建了一个简单的页面项目,它检查单个输入数据字段“名称”,如果它为空或大小小于 5,它必须显示错误消息。

目前 BindingResult 认为一直没有错误。

Spring.xml 文件:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd">


    <!-- Step 3: Add support for component scanning -->
    <context:component-scan base-package="com.mvc" />

    <!-- Step 4: Add support for conversion, formatting and validation support -->
    <mvc:annotation-driven/>

    <!-- Step 5: Define Spring MVC view resolver -->
    <bean
            class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/view/" />
        <property name="suffix" value=".jsp" />
    </bean>


</beans>

学生班级:

package com.mvc;

import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

    public class Student {

        @NotNull(message = "IsRequired!")
        @Size(min = 5, message = "must be greater than 5!")
        private String name;

        public String getName() {
            return name;
        }

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

控制器:

package com.mvc;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.validation.Valid;

@Controller
public class StudentController {

    @RequestMapping("/")
    public String showPage(Model model){
        model.addAttribute("student", new Student());

        return "index";
    }

    @RequestMapping("/processForm")
    public String processForm(
            @Valid @ModelAttribute("student") Student student,
            BindingResult theBindingResult) {

        if (theBindingResult.hasErrors()) {
            return "index";
        } else {
            return "student-confirm";
        }
    }



}

如果需要,我可以发布 web.xml 和 jsp 页面。

标签: spring-mvc

解决方案


删除了以前版本的 Tomcat(7.0) 并安装了最新版本。


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