springboot整合filter方式二

1.创建一个springboot项目

package com.test;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.boot.web.servlet.ServletListenerRegistrationBean;
import org.springframework.boot.web.servlet.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.util.concurrent.ListenableFutureCallbackRegistry;

import com.test.filter.SecondFilter;
import com.test.listener.SecondListener;
import com.test.servlet.Hello02Servlet;

@SpringBootApplication
public class App2 {
	public static void main(String[] args) {
		SpringApplication.run(App2.class, args);
	}
	@Bean
	public FilterRegistrationBean getFilter(){
		FilterRegistrationBean bean =new FilterRegistrationBean(new SecondFilter());
		bean.addUrlPatterns("/hello02");
		return bean;
	}
}

2.创建一个filter类

package com.test.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.annotation.WebFilter;
/**
 * <filter>
 * 		<filter-name>first<filter-name>
 * 		<filter-class>com.test.filter.FirstFilter<filter-class>
 * </filter>
 * <filter-mapping>
 * 		<filter-name>first<filter-name>
 * 		<url-pattern>/hello02</url-pattern>
 * </filter-mapping>
 * @author 26920
 */
public class SecondFilter implements  Filter{
	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		// TODO Auto-generated method stub
	}
	@Override
	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
			throws IOException, ServletException {
		System.out.println("servlet执行之前=========");
		chain.doFilter(request, response);
		System.out.println("servlet执行之后============");
	}
	@Override
	public void destroy() {
		// TODO Auto-generated method stub
	}
}

3.filter类中不需要添加任何代码，在springboot启动类中添加一个方法实例化filter，方法名随意，返回类型必须为FilterRegistrationBean，方法中可设置访问路径以及过滤器的拦截路径的先后顺序（我有一篇博客有这个说明）。