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1、什么是拦截器

  Spring MVC中的拦截器(Interceptor)类似于Servlet中的过滤器(Filter),它主要用于拦截用户请求并作相应的处理。例如通过拦截器可以进行权限验证、记录请求信息的日志、判断用户是否登录等SpringMVC中通过实现HandlerInterceptor接口实现自定义拦截器类。

2、 拦截器案例

1MyIntercept

package com.springmvc.intercept;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class MyIntercept implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("=========拦截器当中的handle方法=========");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("=======在HandlerAdapter之后执行,在DispatcherServlet解析视图之前执行=====");
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("=========呈现之后调用=========");
    }
}
代码实现

2)拦截器配置spring-mvc.xml

<!--利用default-servlet放行资源-->
<mvc:default-servlet-handler/>

<!--配置拦截器-->
<mvc:interceptors>
    <mvc:interceptor>
        <mvc:mapping path="/my/**"/>
        <bean class="com.springmvc.intercept.MyIntercept"></bean>
    </mvc:interceptor>
</mvc:interceptors>
代码实现

(3)MyController

@Controller
@RequestMapping("/my")
public class MyController {
    @RequestMapping("/doFirst")
    public String doFirst(){
        System.out.println("=========控制器中的方法=========");
        return "index";
    }
代码实现

(4)控制台效果

 

3、Spring MVC的数据校验

 3.1 数据校验案例

1)导入依赖

<!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-validator -->
<dependency>
  <groupId>org.hibernate</groupId>
  <artifactId>hibernate-validator</artifactId>
  <version>5.4.1.Final</version>
</dependency>
代码实现

2validate.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>测试案例</title>
</head>
<body>
    <form action="/my/validate" method="post">
        编号:<input type="text" name="uid"/><br/>
        姓名:<input type="text" name="uName"/><br/>
        邮箱:<input type="text" name="email"/><br/>
        电话:<input type="text" name="phone"/><br/>
        身份证号:<input type="text" name="userCode"/><br/>
        <input type="submit" value="提交"/>
    </form>
</body>
</html>
代码实现

(3)实体类UserInfo

package com.springmvc.entity;


import org.hibernate.validator.constraints.Email;
import org.hibernate.validator.constraints.Length;

import javax.validation.constraints.NotNull;
import javax.validation.constraints.Pattern;

public class UserInfo {

    @NotNull(message="编号不能为空")
    private Integer uid;

    @NotNull
    @Length(min = 2,max = 8,message = "用户名不能少于2位或大于8位")
    private String uName;

    @Email(message = "邮箱格式不正确")
    private String email;

    @Pattern(regexp = "/^1[3456789]\\d{9}$/",message = "手机号式不正确")
    private String phone;

    @Pattern(regexp = "/(^\\d{15}$)|(^\\d{18}$)|(^\\d{17}(\\d|X|x)$)/",message = "身份证号格式不正确")
    private String userCode;

    public Integer getUid() {
        return uid;
    }

    public void setUid(Integer uid) {
        this.uid = uid;
    }

    public String getuName() {
        return uName;
    }

    public void setuName(String uName) {
        this.uName = uName;
    }

    public String getEmail() {
        return email;
    }

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

    public String getPhone() {
        return phone;
    }

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

    public String getUserCode() {
        return userCode;
    }

    public void setUserCode(String userCode) {
        this.userCode = userCode;
    }
}
代码实现

(4)MyController

package com.springmvc.controller;

import com.springmvc.entity.UserInfo;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.validation.ObjectError;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.validation.Valid;
import java.util.List;

@Controller
@RequestMapping("/my")
public class MyController {
    @RequestMapping("/doFirst")
    public String doFirst(){
        System.out.println("=========控制器中的方法=========");
        return "index";
    }

    @RequestMapping("/validate")
    public String Validate(@Valid UserInfo info, BindingResult bindingResult){
        //如果有异常信息
        if (bindingResult.hasErrors()){
            //获取异常信息对象
            List<ObjectError> allErrors = bindingResult.getAllErrors();
            //将异常信息输出
            for (ObjectError errors:allErrors) {
                System.out.println(errors.getDefaultMessage());
            }
        }
        return "index";
    }
}
代码实现

(5)效果展示

 

 

 

 

posted on 2019-11-12 17:06  关耳er  阅读(683)  评论(0编辑  收藏  举报