在访问服务器时，我们需要控制用户是否允许权限，这个时候可以使用过滤器。

在springboot 配置过滤器的方法如下：

编写过滤器代码：

package com.neo.filter;import java.io.IOException;import javax.servlet.Filter;import javax.servlet.FilterChain;import javax.servlet.FilterConfig;import javax.servlet.ServletException;import javax.servlet.ServletRequest;import javax.servlet.ServletResponse;import javax.servlet.http.HttpServletRequest;public class MyFilter implements Filter {    @Override    public void destroy() {    }    @Override    public void doFilter(ServletRequest srequest, ServletResponse sresponse, FilterChain filterChain)            throws IOException, ServletException {        HttpServletRequest request = (HttpServletRequest) srequest;        System.out.println("this is MyFilter,url :"+request.getRequestURI());        filterChain.doFilter(srequest, sresponse);    }    @Override    public void init(FilterConfig arg0) throws ServletException {    }}

编写加载过滤器代码：

package com.neo.conf;import org.springframework.boot.web.servlet.FilterRegistrationBean;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import com.neo.filter.MyFilter;import com.neo.filter.MyFilter2;@Configurationpublic class WebConfiguration {        @Bean    public FilterRegistrationBean registerFilter() {        FilterRegistrationBean registration = new FilterRegistrationBean();        registration.setFilter(new MyFilter());        registration.addUrlPatterns("/*");        registration.addInitParameter("paramName", "paramValue");        registration.setName("MyFilter");        registration.setOrder(1);        return registration;    }        @Bean    public FilterRegistrationBean registerFilter2() {        FilterRegistrationBean registration = new FilterRegistrationBean();        registration.setFilter(new MyFilter2());        registration.addUrlPatterns("/*");        registration.addInitParameter("paramName", "paramValue");        registration.setName("MyFilter2");        registration.setOrder(2);        return registration;    }}

这里我们看到我们注册了两个过滤器，过滤器的执行顺序通过setOrder确定。