Spring Boot之FilterRegistrationBean-自定义Filter详解

Spring Boot之FilterRegistrationBean-自定义Filter

项目老的用spring写的，新的升级到了springboot,原代码中有在web.xml中定义过滤器，在boot中，自然没法这样用了，因而看了看boot如何使用自定义过滤器。

在springboot 中，主要是靠FilterRegistrationBean 这个类来提供这样的功能。

自定义 Filter

我们常常在项目中会使用 filters 用于录调用日志、排除有 XSS 威胁的字符、执行权限验证等等。Spring Boot 自动添加了 OrderedCharacterEncodingFilter 和 HiddenHttpMethodFilter，并且我们可以自定义 Filter。

两个步骤：

1、实现 Filter 接口，实现 Filter 方法
2、添加 @Configuration 注解，将自定义Filter加入过滤链

好吧，直接上代码

				?

									package com.zoo.lion.modules.test.test; 

									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;

									/**

									 * @Author: xf

									 * @Date: 2019/7/16 13:39

									 * @Version 1.0

									 */

									@Configuration

									public class WebConfiguration {

									    @Bean

									    public RemoteIpFilter remoteIpFilter() {

									        return new RemoteIpFilter();

									    }

									    @Bean

									    public FilterRegistrationBean<MyFilter> testFilterRegistration() {

									        FilterRegistrationBean<MyFilter> registration = new FilterRegistrationBean<>();

									        registration.setFilter(new MyFilter());

									        //过滤应用程序中所有资源,当前应用程序根下的所有文件包括多级子目录下的所有文件，注意这里*前有“/”

									        registration.addUrlPatterns("/*");

									        //过滤指定的类型文件资源, 当前应用程序根目录下的所有html文件，注意：*.html前没有“/”,否则错误

									        registration.addUrlPatterns(".html");

									        //过滤指定的目录下的所有文件,当前应用程序根目录下的folder_name子目录（可以是多级子目录）下所有文件

									        registration.addUrlPatterns("/folder_name/*");

									        //过滤指定文件

									        registration.addUrlPatterns("/index.html");

									        registration.addInitParameter("paramName", "paramValue");

									        registration.setName("MyFilter");

									        registration.setOrder(1);

									        return registration;

									    } 

									    public class MyFilter implements Filter { 

									        @Override

									        public void init(FilterConfig filterConfig) {

									        }

									        @Override

									        public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {

									            HttpServletRequest request2 = (HttpServletRequest) request;

									            System.out.println(request2.getRequestURI());

									            chain.doFilter(request, response);

									        }

									        @Override

									        public void destroy() { 

									        }

									    }

									}

SpringBoot FilterRegistrationBean对象支持web的filter的排序

1.FilterRegistrationBean对象可以实现对web Filter的排序，使用setOrder(int i)方法

具体代码如下：

				?

									package com.dbzhang;

									/**

									 * @author zdb

									 * @description @Configuration和@Bean注解配置使用，就相当于在配置文件中配置bean的注解式用法

									 */

									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;

									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;

									@Configuration

									public class WebConfiguration {

									    @Bean

									    public RemoteIpFilter remoteIpFilter(){

									        return new RemoteIpFilter();

									    }

									    /***

									     * 这个FilterRegistrationBean类可以使用setOrder()方法实现对filter的排序，然后在进行注册

									     * https://blog.csdn.net/doctor_who2004/article/details/56055505

									     */

									    public FilterRegistrationBean testFilterRegistration(){

									        FilterRegistrationBean registration = new FilterRegistrationBean();

									        registration.setFilter(new MyFilter());

									        registration.addUrlPatterns("/*");

									        registration.addInitParameter("paramName", "paramValue");

									        registration.setName("MyFilter");

									        registration.setOrder(1);

									        return registration;

									    }

									    /**

									     * 

									     * @author zdb

									     * @description 这个是用来实现Filter

									     *

									     */

									    public class MyFilter implements Filter{ 

									        @Override

									        public void destroy() {         

									        }

									        @Override

									        public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)

									                throws IOException, ServletException {

									            HttpServletRequest request = (HttpServletRequest)servletRequest;

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

									            filterChain.doFilter(servletRequest, servletResponse);

									        }

									        @Override

									        public void init(FilterConfig arg0) throws ServletException {           

									        }       

									    }

									}