请问大家这个什么错误啊!!!
<%@   page   contentType= "text/html;   charset=GBK "   %>  
  <html>  
  <head>  
  <title>  
 df 
  </title>  
  </head>  
  <body   bgcolor= "#ffffff ">  
  <form   action= "df.jsp "   method= "post "   name= "form ">  
 用户名 <input   type= "text "   name= "name ">  <br   />  
 密码 <input   type= "password "   name= "password ">  <br   />  
  <center   >  
  <input      type= "submit "   name= "submit "   value= "验证 "/>  </center>  
  </form>  
  <%String   name=request.getParameter( "name "); 
       String   password=request.getParameter( "password "); 
       if(password.equals( "go ")){ 
                               session.setAttribute( "name ", "ok "); 
                               session.setAttribute( "mess ", "你好,你已经验证成功 ");   
       }else{session.setAttribute( "name ", "no "); 
       session.setAttribute( "mess ", "qing   chong      denglu    ");   
 } 
 response.sendRedirect( "2.jsp ");%>      
  </body>  
  </html>      
 rg.apache.jasper.
JasperException     org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:372) 
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292) 
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236) 
    javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 
 root   cause   
java.lang.NullPointerException     org.apache.jsp.df_jsp._jspService(df_jsp.java:58) 
    org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:94) 
    javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 
    org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:324) 
    org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292) 
    org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236) 
    javax.servlet.http.HttpServlet.service(HttpServlet.java:802) 
 note   The   full   stack   trace   of   the   root   ca   
------解决方案--------------------up
------解决方案--------------------NullPointerException 空指針異常   
 調試一下你的name和password有沒有值
------解决方案-------------------- <%@ page contentType= "text/html; charset=GBK " %>  
  <html>  
  <head>  
  <title>  
 df 
  </title>  
  </head>  
  <body bgcolor= "#ffffff ">  
  <form action= "df.jsp " method= "post " name= "form ">  
 用户名 <input type= "text " name= "name ">  <br />  
 密码 <input type= "password " name= "password ">  <br />  
  <center >  
  <input