when I click search button, I can't get an accurate output. I want the query get the output based on selected comparison operator but it not working...below are my trial coding in JSP

 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
   "http://www.w3.org/TR/html4/loose.dtd">
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@ page import="java.sql.*" %>
<%@ page import="java.io.*" %>
 
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>contion three testing</title>
</head>
 
<body>
<form name="form1" method="post" action="">
<table width="520" border="2">
 
    <tr bgcolor="#99CCCC">
      <th width="190" scope="row">DATA ID</th>
      <td width="222"><input type="text" name="textfield"></td>
    </tr>
    <tr bgcolor="#99CCCC">
      <th scope="row">VALID START DATE</th><td>
          <select name="select1" size="1">
        <option value="-1">--Select Operator--</option>
        <option value="=">=</option>
        <option value=">">></option>
        <option value=">=">>=</option>
      </select>
      <input type="text" name="text1" </td>
    </tr>
    <tr bgcolor="#99CCCC">
 
  </table>
  <p>    <input type="submit" name="Submit" value="Search">
 
    <input type="reset" name="Reset" value="Reset">
    <%
 
String id =request.getParameter("textfield");
String list1=request.getParameter("select1");
String start = request.getParameter("text1");
 
 
                        Connection con = null;
                        Statement stmt = null;
 
                        String connectionURL = "jdbc:mysql://localhost:3306/test";
                        Class.forName("com.mysql.jdbc.Driver").newInstance();
                        con = DriverManager.getConnection(connectionURL, "root", "farham");
                        stmt = con.createStatement();
 
 
 
                      String qry ="select data_id,date_format(transaction_date,'%d/%m/%Y')as transaction_date,operator1,date_format(valid_from,'%d/%m/%Y')as valid_from," +
                                 "operator2,date_format(valid_until,'%d/%m/%Y')as valid_until from time_element where data_id='"+id+"'";
 
 
 
                     if(list1!=null && (list1.equals("="))){
                       qry+="and date_format(valid_from,'%d/%m/%Y')='"+start+"'";
                         }
 
 
                    else if(list1!=null && (list1.equals(">"))){
                       qry+="and date_format(valid_from,'%d/%m/%Y')>'"+start+"'";
                         }
 
                      else{
                     qry+="and date_format(valid_from,'%d/%m/%Y')>='"+start+"'";
                  }
 
 
 
  ResultSet rst = stmt.executeQuery(qry);
 
%>
 
  </p>
  <p><table width="785" border="3" bordercolor="#99CCCC">
 
     <td width="32"><div align="center"><strong>Data Id</strong></div></td>
      <td width="124"><div align="center"><strong>Transaction Date </strong></div></td>
      <td width="110"><div align="center"><strong>Operator1 </strong></div></td>
      <td width="124"><div align="center"><strong>Valid Start Date </strong></div></td>
      <td width="110"><div align="center"><strong>Operator2 </strong></div></td>
      <td width="124"><div align="center"><strong>Valid End Date </strong></div></td>
 
 
      <%  while (rst.next()) {
 
%>
      <tr>
    <td><div align="center"><%=rst.getString("data_id")%></div></td>
    <td><div align="center"><%=rst.getString("transaction_date")%></div></td>
    <td><div align="center"><%=rst.getString("operator1")%></div></td>
    <td><div align="center"><%=rst.getString("valid_from")%></div></td>
    <td><div align="center"><%=rst.getString("operator2")%></div></td>
    <td><div align="center"><%=rst.getString("valid_until")%></div></td>
 
      </tr>
 
      <%}
 
 
      %>
 
 
 
 
 
  </table>
 
</form>
</body>
</html>