displaying resultset values from servlet to jsp page

Question

i am fetching the data from database by servlet and then setting it to resultset. Now i want to dislay data on the jsp page. for that i used list to set all data and with jstl i displayed at jsp page. but i am getting two column with same data. Here is the code..

SERVLET CODE:

ResultSet rs = stmt.executeQuery(query);

            while (rs.next()) {

                wb.setDeviceAccount(rs.getString("accountID"));
                wb.setVehicleId(rs.getString("deviceID"));
                wb.setSimNumber(rs.getString("simID"));
                wb.setImeiNumber(rs.getString("imeiNumber"));
                wb.setLastTimestamp(rs.getString("lastGPSTimestamp"));
                wb.setLastLoginTime(rs.getString("lastUpdateTime"));
                wb.setExpirationTime(rs.getString("expirationTime"));
                list.add(wb);

            }
            rs.close();
            stmt.close();
            con.close();
            request.setAttribute("deviceList", list);

            RequestDispatcher requestDispatcher = request.getRequestDispatcher("/installedDeviceList.jsp");
            requestDispatcher.forward(request, response);

JSP PAGE:

<c:forEach items="${deviceList}" var="dList">
                <tr>
                    <td></td>
                    <td>${dList.deviceAccount}</td>
                    <td>${dList.vehicleId}</td>
                    <td><a href="#" onclick="toggle();">${dList.simNumber}</a></td>
                    <td>${dList.imeiNumber}</td>
                    <td>${dList.lastTimestamp}</td>
                    <td>${dList.lastLoginTime}</td>
                </tr>
            </c:forEach>

Answer 1

IN your loop always create new reference of Wb. here i am assuming Wb is your class name.you can change code based on your class name.

Wb wb=null;


ResultSet rs = stmt.executeQuery(query);    
            while (rs.next()) {   

                wb =new Wb();  

                wb.setDeviceAccount(rs.getString("accountID"));
                wb.setVehicleId(rs.getString("deviceID"));
                wb.setSimNumber(rs.getString("simID"));
                wb.setImeiNumber(rs.getString("imeiNumber"));
                wb.setLastTimestamp(rs.getString("lastGPSTimestamp"));
                wb.setLastLoginTime(rs.getString("lastUpdateTime"));
                wb.setExpirationTime(rs.getString("expirationTime"));
                list.add(wb);

            }

Answer 2

You are creating only one object apparently while you should be creating a unique 'wb' instance for each row. You don't have two duplicate rows, you simply add the exact same object multiple times to the list.

Answer 3

For each of the row in result set, create a new wb object to store data from resultset and add the same to list.

Example:

while ( rs.next() ) {
    // set this to equivalent class on your wb variable.
    // wb = new wb();

    wb.setDeviceAccount( rs.getString( "accountID" ) );
    // read other column values here and set in wb
    // ...

    // lastly
    list.add( wb );
} // while rs

Then on your web page, you will get each record read correctly from the list.