public class HttpFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        log.info("do filter, {}, {}", Thread.currentThread().getId(), request.getServletPath());
        RequestHolder.add(Thread.currentThread().getId());
        filterChain.doFilter(servletRequest, servletResponse);
    }

    @Override
    public void destroy() {

    }
}

@SpringBootApplication
public class ConcurrencyApplication implements WebMvcConfigurer {


    @Resource
    private HttpInterceptor httpInterceptor;

    public static void main(String[] args) {
        SpringApplication.run(ConcurrencyApplication.class, args);
    }

    /***
     * 实现过滤器功能
     * @return
     */
    @Bean
    public FilterRegistrationBean httpFilter(){
        FilterRegistrationBean registrationBean = new FilterRegistrationBean();
        registrationBean.setFilter(new HttpFilter());
        registrationBean.addUrlPatterns("/threadLocal/**");
        return registrationBean;
    }

看控制台，没有走都Filter方法，但是init方法却实现了