SpringBoot自定義Filter

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SpringBoot自定義Filter

SpringBoot自動添加了OrderedCharacterEncodingFilter和HiddenHttpMethodFilter，當然我們可以自定
義Filter。

自定義Filter需要兩個步驟：

1. 實現Filter【javax.servlet.Filter】接口，實現Filter方法
2. 添加 @Configuration 注解，將自定義Filter加入過濾鏈

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【過濾打印請求URL】實例代碼如下：

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());//添加過濾器

        registration.addUrlPatterns("/*");//設置過濾路徑，/*所有路徑

        registration.addInitParameter("name", "alue");//添加默認參數

        registration.setName("MyFilter");//設置優先級

        registration.setOrder(1);//設置優先級

        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;

            //打印請求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() 這個方法返回的FilterRegistrationBean如何在Coltroller中獲取？，(●’◡’●)，我很好奇，，於是乎！搞了點事情

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在Controller中獲取剛才ConfigurationFilter中【registration.addInitParameter(“name”, “alue”);//添加默認參數】這個設置的參數。

在Controller中加入如下代碼就能獲取（剛才【testFilterRegistration()】方法加了注解@Bean，所以Spring容器中會有一個實例， @Autowired就理所應當的注入進來了。）

    @Autowired

    FilterRegistrationBean registration;



    @GetMapping("/getname")

    public Map<String, String> getName() {

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

        return initParameters;

    }