技術標籤：springboot過濾器filterjavaspring boot

過濾器

//@WebFilter這個註解是Servlet3.0的規範，並不是Spring boot提供的。
//所以除了這個註解以外，我們還需在配置類中加另外一個註解：@ServletComponetScan，指定掃描的包。
//filter中/*是全部攔截  inteceptor中/**是全部攔截
@WebFilter(filterName = "RequestUrlFilter",urlPatterns = "/*")    
public class RequestUrlFilter
 
 implements Filter {
     /**
     * filter物件只會建立一次，init方法也只會執行一次，在專案啟動的時候進行初始化。
     */
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("RequestUrlFilter init...");  
    }

    @Override
    public void doFilter(ServletRequest servletRequest,
 
 ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) servletRequest;
        String requestURI = req.getRequestURI();
        System.out.println("------->請求地址："+requestURI);
        if(requestURI.
 
contains("demo")){
            HttpServletResponse response = (HttpServletResponse) servletResponse;
            response.sendRedirect("http://www.baidu.com");
        }else{
            filterChain.doFilter(servletRequest,servletResponse);
        }
    }

    @Override
    public void destroy() {
        System.out.println("RequestUrlFilter destory...");
    }
}

主配置類

@SpringBootApplication()
@ServletComponentScan("com.jarvis.msgserver.filter")  //掃描過濾器
public class MsgServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(LanjieqiApplication.class, args);
    }
}