springboot 使用Servlet,Filter,Listener的方法

分别通过构建下面bean来，使用filter,servlet,servletlistener

FilterRegistrationBean 、
ServletRegistrationBean 、
ServletListenerRegistrationBean

这三个类

直接上代码:

@Bean    public FilterRegistrationBean filterRegistrationBean() {        FilterRegistrationBean registrationBean = new FilterRegistrationBean();        CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter();        characterEncodingFilter.setEncoding("UTF-8");        registrationBean.setFilter(characterEncodingFilter);        return registrationBean;    }    @Bean    public ServletRegistrationBean servlet(){        return new ServletRegistrationBean();    }    @Bean    public ServletListenerRegistrationBean<EventListener>(){        return new ServletListenerRegistrationBean<>(new EventListener());    }