SpringBoot设置拦截器

1、创建我们自己的拦截器类并实现HandlerInterceptor接口。
2、创建-个Java类继承WebMvcConfigurerAdapter, 并写addInterceptors方法。
2、实例化我们自定义的拦截器，然后将对像手动添加到拦截器链中。

先来自定义一个MyInterceptor拦截器;
拦截器- -般需要继承HandlerInterceptor接口， 并需要实现以下三个接口
方法:

package com.newdo.base;

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

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.Map;

public class MyInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
    //获取请求中的session
        String userCode = (String) request.getSession().getAttribute("UserCode");
        if (userCode==null){
           //跳转的地址
            request.getRequestDispatcher("/login").forward(request,response);
            return false;
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

    }
}

拦截器定义完成后，还需要将拦截器注册才能生效，并指定该拦截器所拦
截的场景。
创建MyWebMvcConfig继承WebMvcConfigurerAdapter,并重写
addInterceptors方法

package com.newdo.configuration;

import com.newdo.base.MyInterceptor;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.Ordered;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

@Configuration
public class DefaultWebConfiguration implements WebMvcConfigurer {

    @Bean
    public MyInterceptor myInterceptor(){
        return new MyInterceptor();
    }

    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(myInterceptor())
                .addPathPatterns("/**") //拦截所有路径
                .excludePathPatterns("/login","/","/getValidCode")  //排除路径
                .excludePathPatterns("/static/**"); //排除静态资源路径
    }

跟拦截器相关的执行流程如下：

测试-直接访问主页,拦截器自动拦截所有请求,判断用户是否登录,否–跳转到登录页面

原文地址：https://www.cnblogs.com/wx60079/p/12841733.html