springboot的filter过滤器的用法

1. 在项目下创建一个包，包名为filter

2. 在filter包下创建一个类型，命名随便

3. 然后配置过滤器

   1. 给类加上过滤器的注释@WebFilter(filename = "filtername",urlPatterns = "/*")filtername用来设置过滤器的名称,urlPatters配置过滤器作用于那些文件
   2. 实现Filter接口

   package com.xiaowei.reggie.filter;
   
   
   import javax.servlet.*;
   import javax.servlet.annotation.WebFilter;
   import java.io.IOException;
   
   /**
    * filterName 配置改过滤器的名称
    */
   @WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
   public class LoginCheckFilter implements Filter {
       @Override
       public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
           System.out.println("进入过滤器");
           filterChain.doFilter(servletRequest, servletResponse);
       }
   }
   

4. 然后再启动类ReggieApplication中配置注解@ServletComponentScan

   package com.xiaowei.reggie;
   
   import lombok.extern.slf4j.Slf4j;
   import org.springframework.boot.SpringApplication;
   import org.springframework.boot.autoconfigure.SpringBootApplication;
   import org.springframework.boot.web.servlet.ServletComponentScan;
   
   @Slf4j
   @SpringBootApplication
   @ServletComponentScan
   public class ReggieApplication {
       public static void main(String[] args) {
           SpringApplication.run(ReggieApplication.class,args);
           log.info("项目启动成功~~");
       }
   }
   
   

5. 重启项目