1.首先pom.xml需要引用两个jar包（spring-mvc需要的包这里就不赘述了），如下：
<dependency> <groupId>javax.validation</groupId> <artifactId>validation-api</artifactId> <version>1.1.0.Final</version> </dependency> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-validator</artifactId> <version>5.1.2.Final</version> </dependency>
2.定义一个需要输入的对象Product
package cn.duanjt.pojo; import java.util.Date; import javax.validation.constraints.DecimalMin; import javax.validation.constraints.Size; import org.springframework.format.annotation.DateTimeFormat; public class Product { //定义验证规则 @DecimalMin("0.01") private int price; @Size(max=10,min=1) private String name; @DateTimeFormat(pattern="yyyy-MM-dd") private Date time; private String email; /** getter and setter，这里为了简洁就这么写了 **/ }
3.定义控制器
package cn.duanjt; import java.util.ArrayList; import java.util.List; import javax.validation.Valid; import org.springframework.stereotype.Controller; import org.springframework.validation.Errors; import org.springframework.validation.FieldError; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.servlet.view.json.MappingJackson2JsonView; import com.google.gson.Gson; import cn.duanjt.pojo.Product; import cn.duanjt.pojo.Student; @Controller @RequestMapping("/student") public class StudentController { //注意：@Valid @RequestMapping("/save") public ModelAndView save(@Valid Product product, Errors errors) { if (errors.hasErrors()) { System.out.println("验证失败"); List<FieldError> fieldErrors = errors.getFieldErrors(); for (FieldError fe : fieldErrors) { System.out.println(fe.getField() + " " + fe.getDefaultMessage());//输出错误消息 } } else { System.out.println("验证成功"); } System.out.println(new Gson().toJson(product));//输出获取的对象 ModelAndView mv = new ModelAndView(); mv.addObject(product); mv.setView(new MappingJackson2JsonView()); return mv; } }
4.jsp代码测试如下：
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>首页</title> </head> <body> <form action="student/save.do" method="post"> <p> 单价：<input type="text" name="price" value="1" /> </p> <p> 名称：<input type="text" name="name" value="茄子" /> </p> <p> 日期：<input type="text" name="time" value="2018-07-21" /> </p> <p> 邮件：<input type="text" name="email" /> </p> <p> <input type="submit" value="提交"/> </p> </form> </body> </html>
最后附上验证规则：
