package com.cy.example.config;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.web.servlet.HandlerInterceptor;import org.springframework.web.servlet.ModelAndView;public class LoginInterceptor implements HandlerInterceptor {  private Logger logger = LoggerFactory.getLogger(LoginInterceptor.class);  public void postHandle(HttpServletRequest request,      HttpServletResponse response, Object handler,      ModelAndView modelAndView) throws Exception {    // TODO Auto-generated method stub  }  public void afterCompletion(HttpServletRequest request,      HttpServletResponse response, Object handler, Exception ex)      throws Exception {    // TODO Auto-generated method stub  }  public boolean preHandle(HttpServletRequest request,      HttpServletResponse response, Object handler) throws Exception {    // TODO Auto-generated method stub    //獲取session    HttpSession session = request.getSession(true);    logger.info("----進入登錄攔截器--url："+request.getServletPath()+"-----");    if(session.getAttribute(WebConfig.LOGIN_USER) == null){      logger.info("------跳轉到login頁面-----");      response.sendRedirect(request.getContextPath()+"/index");      return false;    }else{      session.setAttribute(WebConfig.LOGIN_USER, session.getAttribute(WebConfig.LOGIN_USER));      return true;    }  }}

package com.cy.example.config;import org.springframework.context.annotation.Configuration;import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;import org.springframework.web.servlet.config.annotation.InterceptorRegistry;import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;@Configurationpublic class WebConfig extends WebMvcConfigurerAdapter {  public static String LOGIN_USER = "loginUser";  public WebConfig() {    super();  }  //因為新加了攔截器，這里需要重新設置資源地址  @Override  public void addResourceHandlers(ResourceHandlerRegistry registry) {    registry.addResourceHandler("/static/**").addResourceLocations(        "classpath:/static/");    registry.addResourceHandler("/templates/**").addResourceLocations(        "classpath:/templates/");    super.addResourceHandlers(registry);  }  @Override  public void configureDefaultServletHandling(      DefaultServletHandlerConfigurer configurer) {    configurer.enable();  }  @Override  public void addInterceptors(InterceptorRegistry registry) {    // 攔截規則：除了login，其他都攔截判斷,excludePathPatterns是排除攔截的路徑，一個是登錄驗證地址，一個是登錄頁    registry.addInterceptor(newLoginInterceptor()).addPathPatterns("/**").excludePathPatterns("/index","/system/user/validate");    super.addInterceptors(registry);  }}