Arraylist, query e jsp

Boa tarde pessoal ! Necessito da ajuda de você pois não consigo retornar uma pesquisa de um determinado número de conta, se eu quiser que seja exibido os resultados tenho que colocar no código dentro cláusula WHERE o número da conta.

Meu SERVLET

[code]public class Controler extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
 * @see HttpServlet#HttpServlet()
 */
public Controler() {
    super();
    // TODO Auto-generated constructor stub
}

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	// TODO Auto-generated method stub
}

/**
 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
 */
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	String cmd = request.getParameter("cmd");
			

	
	if(cmd.equalsIgnoreCase("Conta") ){
		Extrato.mostrarExtrato(request, response);
		response.sendRedirect("extrato.jsp");
	}
	
			
}

[/code]

CLASSE EXTRATO

[code]package servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import servlet.TransacaoBean;

public class Extrato {

public static List mostrarExtrato(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{

	String numero = request.getParameter("txtConta");
	
	PrintWriter out = response.getWriter();
	
	HttpSession session = request.getSession();
	

	response.setContentType("text/html");
	
	out.println("<html>");
	out.println("<body>");
	List <TransacaoBean> transacoes = new ArrayList<TransacaoBean>();
	
	try{
		
		
		Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
		
		Connection con = DriverManager.getConnection("jdbc:odbc:BANCOFATEC");
		
		PreparedStatement pstmt = con.prepareStatement("SELECT * FROM HISTORICO WHERE NUMEROCONTA = 12345678"); //NESTA PARTE ELE NÃO PEGA O NÚMERO DA CONTA DIGITADA NA PÁGINA CONTA.JSP PARA MOSTRAR AS TRANSAÇÕES DA MESMA NA PÁGINA EXTRATO.JSP
	
		//pstmt.setString (1, numero);
		
		ResultSet rs = pstmt.executeQuery();
		
		while(rs.next()){

			TransacaoBean transacao = new TransacaoBean();
			
			transacao.setNumeroConta(rs.getString("numeroConta"));
			transacao.setValor(rs.getString("valor"));
			transacao.setDescricao(rs.getString("descricao"));
			
			transacoes.add(transacao);
		}
		
		out.print(transacoes);
		
		
							
	}catch(ClassNotFoundException e){
		e.printStackTrace();
	}catch(SQLException e){
		e.printStackTrace();
	}
	return transacoes;
	
}

}
[/code]

PÁGINA CONTA.JSP

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Login</title>
</head>
<body>
	<form action="./Controler" method="post"> 
		<table border="2">
			<caption>Digite a sua conta para acessar o extrato</caption>
			<tr>
				<td colspan="3"><jsp:include page="./cabecalho.jsp" flush="true"/></td>
			</tr>
			<tr>
				<td>Conta:</td> 
				<td><input type="text" name="txtConta" size="20"/></input></td>			
			</tr>
				
			
			<tr>
				<td align="center"><input type="submit" name="cmd" value="Conta"></input></td>
				<td align="center"><input type="submit" name="cmd" value="Cancela"/></input></td>			
			</tr>	
	
		</table>
	</form>
	<%
		String source = "Login";
	%>
</body>
</html>

PÁGINA EXTRATO.JSP

[code]<%@ page import=“servlet.TransacaoBean” %>
<%@ page import=“servlet.Extrato” %>
<%@ page import=“java.util.*”%>

Extrato
	<h2>EXTRATO</h2>
	<table border="2">
		<tr>
			<td colspan="3"><jsp:include page="./cabecalho.jsp" flush="true"/></td>
		</tr>
		
			<tr>
			<td>Número da Conta</td> 
			<td>Valor</td>
			<td>Descrição</td>			
		</tr>
		
		<%
				Extrato e = new Extrato();
			List<TransacaoBean> transacoes = e.mostrarExtrato(request, response); 
			
			for(TransacaoBean t : transacoes){
									
		%>
		<tr>
			<td><%= t.getNumeroConta() %></td>		
			<td><%= t.getValor() %></td>
			<td><%= t.getDescricao() %></td>
		</tr>
		<%} %>
			
			
		
	</table>
		<center><input type="submit" name="cmd" value="Extrato"/>
</form>
<%
	String source = "Extrato";
%>
[/code]