package com.github.carter659.spring13;

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

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistration;
 
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

/**
 * 登錄配置 博客出處：http://www.cnblogs.com/GoodHelper/
 *
 */
@Configuration
 
public class WebSecurityConfig extends WebMvcConfigurerAdapter {

    /**
     * 登錄session key
     */
    public final static String SESSION_KEY = "user";

    @Bean
    public SecurityInterceptor getSecurityInterceptor() {
        return new SecurityInterceptor();
    }

    public void addInterceptors(InterceptorRegistry registry) {
        InterceptorRegistration addInterceptor 
 
= registry.addInterceptor(getSecurityInterceptor());

        // 排除配置
        addInterceptor.excludePathPatterns("/error");
        addInterceptor.excludePathPatterns("/login**");

        // 攔截配置
        addInterceptor.addPathPatterns("/**");
    }

    private class SecurityInterceptor extends HandlerInterceptorAdapter {

        @Override
        public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler)
                throws Exception {
            HttpSession session = request.getSession();
            if (session.getAttribute(SESSION_KEY) != null)
                return true;

            // 跳轉登錄
            String url = "/login";
            response.sendRedirect(url);
            return false;
        }
    }
}

排除配置那裏，千萬別把，發送過去驗證登錄的網址，也給攔截了，這個原因，折騰了我大半個小時

// 排除配置

addInterceptor.excludePathPatterns("/login**");

https://www.cnblogs.com/GoodHelper/p/6343190.html

使用WebMvcConfigurerAdapter 做登錄，失效的一個小小原因