Springboot项目使用拦截器方法详解

package com.leiyuan.bs.interceptor;import org.springframework.web.servlet.HandlerInterceptor;import org.springframework.web.servlet.ModelAndView;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;// 拦截器public class MyHandlerInterceptor implements HandlerInterceptor {  /**   * 拦截（Controller方法调用之前）   *   * @param request request   * @param response response   * @param o    o   * @return 通过与否   * @throws Exception 异常处理   */  @Override  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object      o) throws Exception {    // TODO 我这里是通过用户是否登陆进行拦截，我的用户信息存储在session中，名称为userSession，大家可以自行实现    if (request.getSession().getAttribute("userSession") == null) {      // 拦截至登陆页面      request.getRequestDispatcher("/user/toLogin").forward(request, response);      // false为不通过      return false;    }    // true为通过    return true;  }  // 此方法为处理请求之后调用（调用过controller方法之后，跳转视图之前）  @Override  public void postHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object o,              ModelAndView modelAndView) throws Exception {  }  // 此方法为整个请求结束之后进行调用  @Override  public void afterCompletion(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse,                Object o, Exception e) throws Exception {  }}

package com.leiyuan.bs;import com.leiyuan.bs.interceptor.MyHandlerInterceptor;import org.springframework.stereotype.Component;import org.springframework.web.servlet.config.annotation.InterceptorRegistry;import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;// 拦截器配置类@Componentpublic class MyHandlerInterceptorConfig extends WebMvcConfigurerAdapter {  @Override  public void addInterceptors(InterceptorRegistry registry) {  	/**     * 这里的addPathPatterns("/**")为配置需要拦截的方法“/**”代表所有，而后excludePathPatterns("/user/toLogin")等方法为排除哪些方法不进行		 拦截     */    registry.addInterceptor(new MyHandlerInterceptor()).addPathPatterns("/**").excludePathPatterns("/user/toLogin").excludePathPatterns        ("/user/login").excludePathPatterns("/user/toNewUser").excludePathPatterns("/user/newUser");    super.addInterceptors(registry);  }}