JSR 303 以及 拦截器

前言

上一篇文章分享了，上传和下载。本片文章将分享的内容是 JSR303 以及 拦截器

---

一、JSR303

        JSR-303 是 JAVA EE 6 中的一项子规范，叫做 Bean Validation，官方参考实现是Hibernate Validator。

        

        简单的说，JSR-303就是用来做表单验证的。

我们之前用js、jQuery做表单验证，JS属于前端的脚本验证（只作用于客户端的浏览器中，可以被屏蔽）

JSR303属于服务端验证

        1、导入pom

<dependency>
      <groupId>org.hibernategroupId>
      <artifactId>hibernate-validatorartifactId>
      <version>6.0.7.Finalversion>
    dependency>
 

        2、Clazz

package com.zhw.model;
 
import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotNull;
 
/**
 * @NotNull ：作用于基本数据类型
 * @NotEmpty    作用于集合
 * @NotBlank    作用于字符串
 */
public class Clazz {
    @NotNull(message = "班级编号不能为空")
    protected Integer cid;
 
    @NotBlank(message = "班级名不能为空")
    protected String cname;
 
    @NotBlank(message = "班级教员老师不能为空")
    protected String cteacher;
 
    protected String pic;
 
    public Clazz(Integer cid, String cname, String cteacher, String pic) {
        this.cid = cid;
        this.cname = cname;
        this.cteacher = cteacher;
        this.pic = pic;
    }
 
    public Clazz() {
        super();
    }
 
    public Integer getCid() {
        return cid;
    }
 
    public void setCid(Integer cid) {
        this.cid = cid;
    }
 
    public String getCname() {
        return cname;
    }
 
    public void setCname(String cname) {
        this.cname = cname;
    }
 
    public String getCteacher() {
        return cteacher;
    }
 
    public void setCteacher(String cteacher) {
        this.cteacher = cteacher;
    }
 
    public String getPic() {
        return pic;
    }
 
    public void setPic(String pic) {
        this.pic = pic;
    }
}

        3、ClazzController

package com.zhw.web;
 
import com.zhw.biz.ClazzBiz;
import com.zhw.model.Clazz;
import com.zhw.model.dto.ClazzDto;
import com.zhw.util.PageBean;
import org.apache.commons.io.FileUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.validation.FieldError;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.multipart.MultipartFile;
 
import