code: @Override
  	public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
  		//-- 处理请求，如果处理失败（无对应的Action），继续后续步骤
  		if(false == ActionContext.handle(req, res)) {
  			chain.doFilter(req, res);
  		}
  	}
docs: 拦截请求
  @param req ServletRequest
  @param res ServletResponse
  @param chain FilterChain