SpringBoot自定义Filter

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SpringBoot自定义Filter

SpringBoot自动添加了OrderedCharacterEncodingFilter和HiddenHttpMethodFilter，当然我们可以自定
义Filter。

自定义Filter需要两个步骤：

1. 实现Filter【javax.servlet.Filter】接口，实现Filter方法
2. 添加 @Configuration 注解，将自定义Filter加入过滤链

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【过滤打印请求URL】实例代码如下：

package xatu.zsl.Filter;



import org.apache.catalina.filters.RemoteIpFilter;

import org.springframework.boot.web.servlet.FilterRegistrationBean;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;



import javax.servlet.*;

import javax.servlet.http.HttpServletRequest;

import java.io.IOException;



/**

 * Created by zsl on 2017/9/3.

 */

@Configuration

public class ConfigurationFilter {

    @Bean

    public RemoteIpFilter remoteIpFilter() {

        return new RemoteIpFilter();

    }



    @Bean

    public FilterRegistrationBean testFilterRegistration() {

        FilterRegistrationBean registration = new FilterRegistrationBean();

        registration.setFilter(new MyFilter());//添加过滤器

        registration.addUrlPatterns("/*");//设置过滤路径，/*所有路径

        registration.addInitParameter("name", "alue");//添加默认参数

        registration.setName("MyFilter");//设置优先级

        registration.setOrder(1);//设置优先级

        return registration;

    }



    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;

            //打印请求Url

            System.out.println("this is MyFilter,url :" + request.getRequestURI());

            filterChain.doFilter(srequest, sresponse);

        }



        @Override

        public void init(FilterConfig arg0) throws ServletException {

        }

    }

}

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有人好奇public FilterRegistrationBean testFilterRegistration() 这个方法返回的FilterRegistrationBean如何在Coltroller中获取？，(●’◡’●)，我很好奇，，于是乎！搞了点事情

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在Controller中获取刚才ConfigurationFilter中【registration.addInitParameter(“name”, “alue”);//添加默认参数】这个设置的参数。

在Controller中加入如下代码就能获取（刚才【testFilterRegistration()】方法加了注解@Bean，所以Spring容器中会有一个实例， @Autowired就理所应当的注入进来了。）

    @Autowired

    FilterRegistrationBean registration;



    @GetMapping("/getname")

    public Map<String, String> getName() {

        Map<String, String> initParameters = registration.getInitParameters();

        return initParameters;

    }