import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import java.io.IOException;
@Component
@WebFilter(filterName="myFilter",urlPatterns = "/*")
public class MyFilter implements Filter {
    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        filterChain.doFilter(servletRequest,servletResponse);
    }
}

@SpringBootApplication
@ComponentScan(value = "com.example")
@ServletComponentScan   //掃描過濾器
public class DemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
}

import org.springframework.web.filter.OncePerRequestFilter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
@WebFilter //繼承OncePerRequestFilter的過濾的類，對每個(gè)請求只會過濾一次，這也是與實(shí)現(xiàn)Filter類不一樣的地方
public class MyOnceProRequestFilter extends OncePerRequestFilter {
    @Override
    protected void doFilterInternal(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, FilterChain filterChain) throws ServletException, IOException {
        filterChain.doFilter(httpServletRequest,httpServletResponse);
    }
}

@Configuration  //表示這是一個(gè)設(shè)置類
public class MyRegistration {
    @Bean
    public FilterRegistrationBean MyRegistrationBean(MyFilter myFilter){
        FilterRegistrationBean<Filter> registrationBean = new FilterRegistrationBean<>();
        registrationBean.setFilter(myFilter);   //設(shè)置過濾器
        registrationBean.setUrlPatterns(Collections.singleton("/*")); //設(shè)置過濾路徑
        registrationBean.setOrder(1);  //設(shè)置優(yōu)先級
        return registrationBean;
    }
}