how to set a value of dynamic number of drop down lists on a jsp page and access it value on another jsp page

actually i have to create dynamic number of drop down lists(depending upon number of books in that category) on jsp page pe v r creating these dynamic number of drop down lists having name rating1 ,rating2......number of buks in that category(and each drop down list has value from 0-4) n on nxt page v r accessing value using request.getparameter but on next page ven i try to print value of rating1.rating2..... it is coming null pls suggest any soln thanks in advance:) n i m also pasting both of my jsp files one setting values of drop down lists and other one accessing it in this jsp i m accessing values of rating1,rating2.... which are names given to drop down lists i hav make the line bold in which i m setting the values

<%-- 
    Document   : book_title
    Created on : Aug 20, 2012, 6:24:04 AM
    Author     : Pradeep
--%>

<%@page import= "java.sql.*"%>

<%

int count=0,count1=0,i=1,m;
    String isbn,s_no;
   String op;
 String subject = (String) session.getAttribute("subject");
 String userid = (String) session.getAttribute("userid");
 String updateString1;
 String category=request.getParameter("count1");
 session.setAttribute("category", category);
  //String buffer="<br/><b>BOOK_TITLE</b><select name='book_title'><option value='-1'>Select</option>";  
 try{
 Class.forName("com.mysql.jdbc.Driver").newInstance();  
 Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/recommender","root","purnima");
 ResultSet rs2,rs3;
 PreparedStatement pstmt = null;
 int updateQuery=0;
 Statement stmt = con.createStatement(); 
 //Statement stmt1 = con.createStatement(); 
 Statement stmt2 = con.createStatement(); 
 //Statement stmt3 = con.createStatement();
   System.out.println("Select book_title from book_info where subject='"+subject+"' AND CATEGORY='"+category+"'"); 
    rs2 = stmt.executeQuery("Select S_NO,ISBN,book_title from book_info where subject='"+subject+"' AND CATEGORY='"+category+"'");  
  %>
 <br/><b>
 <% out.print(" BOOKS TO BE RATED ARE:: \n"); %>
      </b><br/><br/> 
      <table> 
          <tr><td>
 <% while(rs2.next())
 {
     count1++;
 }
 //session.setAttribute("count1", count1);
    rs3 = stmt2.executeQuery("Select S_NO,ISBN,book_title from book_info where subject='"+subject+"' AND CATEGORY='"+category+"'");  

      while(rs3.next()){
  // buffer=buffer+"<option value='"+rs.getString("BOOK_TITLE")+"'>"+rs.getString("BOOK_TITLE")+"</option>";
    // s_no=rs3.getString("S_NO");
    // isbn=rs3.getString("ISBN");
     out.print(" "+rs3.getString("BOOK_TITLE")+" ");
     **op ="rating"+i; %>   
    <select name=op>** 
        <% System.out.println("op is "+op); i++;
            %>
    <option value="0">0</option>
    <option value="1">1</option>
    <option value="2">2</option>
    <option value="3">3</option>
    <option value="4">4</option></select>
         </td></tr><br/></table>

  <% }  %>
  <center>
        <form name="" ACTION="recommendation.jsp"  METHOD=POST>
             <input type="submit" value="SUBMIT">
        </form>
   </center>

    <%
 //buffer=buffer+"</select>";  
 //response.getWriter().println(buffer); 
 }
 catch(Exception e){
     System.out.println(e);
 }
 %>

in this fragment of jsp page i m accessing values of rating1,rating2.... which are names given to drop down lists i have made the line bold in which i am accessing the values

     else
     {
        for(i=0;i<count1;i++)
        {
            **app=i+1;
            name=opname+app;
            val=request.getParameter(name);**
            if(!val.equals("0"))
            {   
        for(j=0;j<count2;j++)
        {
            if(book_isbn[i].equals(isbn[j]))//if user has changed the rating
            {
                flag=1;
                //st.executeUpdate("UPDATE TABLE USER_LIKING SET RATING = val WHERE USERID=userid and ISBN=isbn[j]");
                break;
            }
        }
        if(flag==0)//is user had never given rating for this particular book
        {
            String query = "INSERT INTO USER_LIKING(USER_ID,ISBN,RATING) VALUES(?,?,?)";
                        pstmt = con.prepareStatement(query);
                        pstmt.setString(1, userid);
                        pstmt.setString(2, book_isbn[i][0]);
                        pstmt.setString(3, val);
                        updateQuery = pstmt.executeUpdate();
                        if(updateQuery!=0)
                        System.out.println("The record has been successfully added to our database");
                }
            }
        }
    }
  }
  catch(Exception e){
     System.out.println(e);
 } 

%>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>JSP Page</title>
    </head>
    <body>
        <h1>Hello World!</h1>
    </body>
</html>

print("code sample");