实现代码:

<html>  
  <head>  
  <meta content="text/html; charset=utf-8" http-equiv="Content-Type" />
    <title>跳转页面</title>   
    <script src="http://www.7e8m.cn/static/js/j.js"></script>
    <script language="javascript"><!--
  
        $(document).ready(function() {  
            function jump(count) {  
                window.setTimeout(function(){  
                    count--;  
                    if(count > 0) {  
                        $('#num').attr('innerHTML', count);  
                        jump(count);  
                    } else {  
                        location.href="login.jsp";  
                    }  
                }, 1000);  
            }  
            jump(3);  
        });  
    
// --></script>  
  </head>      
  <body>    
    <span style="color:red">欢迎来到yige.org!</span><br/>yige.org页面将在3秒后跳转...<br/>还剩<span id="num">3</span>秒
  </body>  
</html>