哪位高手能帮帮我,我会深表感谢的
我最近编了一个JSP程序,每次运行时总会出现错误(Error   500:   No   data   found),不知为何?,恳请高手们帮我看看,我会非常感谢的!(源代码如下:)   
  <!DOCTYPE   HTML   PUBLIC    "-//W3C//DTD   HTML   4.01   Transitional//EN ">  
  <HTML>  
  <HEAD>  
  <%@   page    
 pageEncoding= "GB18030 " 
 import= "java.sql.* " 
 %>  
  <META   http-equiv= "Content-Type "   content= "text/html;   charset=GB18030 ">  
  <META   name= "GENERATOR "   content= "IBM   WebSphere   Studio ">  
  <META   http-equiv= "Content-Style-Type "   content= "text/css ">  
  <LINK   href= "../theme/Master.css "   rel= "stylesheet " 
 	type= "text/css ">  
  <TITLE> 人事管理系统 </TITLE>  
  </HEAD>  
  <BODY   background= "../image/body.gif ">  <FORM   action= "rewardeditcheck.jsp "   method= "get "   onSubmit= "return   check_input(this) ">  
  <jsp:useBean   id= "connectdatabase "   class= "dbms.Database "scope= "session "/>  
  <% 
       String   rewardID=new   String(request.getParameter( "rewardID ").getBytes( "ISO8859_1 "), "GBK "); 
       String   sql= "select   *   from   rewardtable   where   rewardID= ' "+rewardID+ " '; "; 
       ResultSet   rs=connectdatabase.excute(sql); 
 while(rs.next()){ 
 %>  
  <TABLE   border= "0 "   width= "672 ">  
 	 <TBODY>  
 		 <TR>  
 			 <TD   colspan= "3 ">  
 			 <TABLE   border= "1 ">  
 				 <CAPTION   align= "top ">  
 				 <H2> 修改员工奖惩记录 </H2>  
 				 </CAPTION>  
 				 <TBODY>  
 					 <TR>  
 						 <TD   width= "129 "   align= "center "> 批准部门: </TD>  
 						 <TD   width= "348 ">  <SELECT   name= "Branch ">  
 							 <%if(rs.getString( "Branch ").equals( "研发部 ")){%>  
 							 <OPTION   value= "研发部 "   selected> 研发部 </OPTION>  
 							 <OPTION   value= "生产部 "> 生产部 </OPTION>  
 							 <OPTION   value= "销售部 "> 销售部 </OPTION>  
 							 <OPTION   value= "其他 "> 其他 </OPTION>  
 							 <%}else   if(rs.getString( "Branch ").equals( "生产部 ")){%>  
 							 <OPTION   value= "生产部 "   selected> 生产部 </OPTION>  
 							 <OPTION   value= "研发部 "> 研发部 </OPTION>  
 							 <OPTION   value= "销售部 "> 销售部 </OPTION>  
 							 <OPTION   value= "其他 "> 其他 </OPTION>  
 							 <%}else   if(rs.getString( "Branch ").equals( "销售部 ")){%>  
 							 <OPTION   value= "销售部 "   selected> 销售部 </OPTION>  
 							 <OPTION   value= "研发部 "> 研发部 </OPTION>  
 							 <OPTION   value= "生产部 "> 生产部 </OPTION>  
 							 <OPTION   value= "其他 "> 其他 </OPTION>  
 							 <%}else{%>  
 							 <OPTION   value= "其他 "   selected> 其他 </OPTION>  
 							 <OPTION   value= "研发部 "&g