以下是一个用户登录的Filter

package com.rs.outcall.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;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.rs.outcall.bean.AdminUser;


@WebFilter(urlPatterns = "/*", filterName = "logFilter")
public class LoginFilter implements Filter {
    
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {
        
        HttpServletRequest request = (HttpServletRequest) req;
        HttpServletResponse response = (HttpServletResponse) res;
        
        String[] notFilter = {"login", "login.jsp", "logout.dispatch", "login.dispatch", ".css", ".js", ".gif", ".png", ".htm",
                ".asp", ".jpg" };

        String uri = request.getRequestURI();
        
        boolean doFilter = true;
        for (String s : notFilter) {
            if (uri.toLowerCase().endsWith(s.toLowerCase())) {

                doFilter = false;
                break;
            }
        }
        
        if (!doFilter) {
            chain.doFilter(request, response);
            return;
        }
        
        HttpSession session = ((HttpServletRequest)request).getSession();
        String loginUser = (String)session.getAttribute("loginUser");
        String url=((HttpServletRequest)request).getRequestURL().toString();
        if(   loginUser==null && url.lastIndexOf("/login.jsp")==-1 && url.lastIndexOf("/login.do")==-1  ){ 
            ((HttpServletResponse)response).sendRedirect("/login.jsp"); 
            
        } 
        else
        { 
            chain.doFilter(request, response); 
        } 
    
    }
    
    public void destroy() {

    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        // TODO Auto-generated method stub  
    }

}

在App里，需要加入@ServletComponentScan，才能找到Filter：

package com.rs.outcall;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;

/**
 * SpringBoot启动类
 *
 *
 */
@SpringBootApplication
@ServletComponentScan("com.rs.outcall.filter")
public class App {

    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }
}