1. 在SpringBootApplication上使用@ServletComponentScan注解后，Servlet、Filter、Listener可以直接通过@WebServlet、@WebFilter、@WebListener注解自动注册，无需其他代码。
    2. 新建Filter过滤器 继承GenericFilterBean并加入注解@WebFilter(filterName = “wmTokenFilter”,urlPatterns = “/*”)
      1. @WebFilter(filterName = "wmTokenFilter",urlPatterns = "/*")
      2. @Log4j2
      3. public class WmTokenFilter extends GenericFilterBean {
      4.  @Override
      5.  public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
      6.      HttpServletRequest request = (HttpServletRequest) servletRequest;
      7.      HttpServletResponse response = (HttpServletResponse) servletResponse;
      8.      //得到header中的信息
      9.      String userId = request.getHeader("userId");
      10.      if(userId != null){
      11.          WmUser wmUser = new WmUser();
      12.          wmUser.setId(Integer.valueOf(userId));
      13.          WmThreadLocalUtils.setUser(wmUser);
      14.      }
      15.      filterChain.doFilter(request,response);
      16.  }
      17. }`