兩種方式
第一種通過FilterRegistrationBean

 @Bean
 public FilterRegistrationBean filterRegistrationBean(){
    return new FilterRegistrationBean(errorPageFilter());
 }

@Bean
public Filter errorPageFilter(){
  ErrorPageFilter errorPageFilter = new ErrorPageFilter();
  ErrorPage notFind = new ErrorPage("/404");
  errorPageFilter.addErrorPages(notFind);
  return errorPageFilter;
}

第二種通過DelegatingFilterProxyRegistrationBean

@Bean
public DelegatingFilterProxyRegistrationBean delegatingFilterProxyRegistrationBean(){
  return new DelegatingFilterProxyRegistrationBean("errorPageFilter");
}

@Bean("errorPageFilter")
public Filter errorPageFilter(){
  ErrorPageFilter errorPageFilter = new ErrorPageFilter();
  ErrorPage notFind = new ErrorPage("/404");
  errorPageFilter.addErrorPages(notFind);
  return errorPageFilter;
}

二者都是繼承同一個父類AbstractFilterRegistrationBean，只是DelegatingFilterProxyRegistrationBean還實現了ApplicationContextAware，注入了ApplicationContext實例，用于查找指定的Filter實例，最終構建的是一個代理Filter實例(DelegatingFilterProxy);FilterRegistrationBean中維護的是目標Filter，結果都是將Filter注冊到ServletContext中，推薦使用FilterRegistrationBean。