leftover.java

网上银行管理系统

package cn.edu.ccut;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.naming.Context;
import javax.sql.DataSource;
import java.sql.*;
import java.io.PrintWriter;
import java.io.IOException;
//import java.io.IOException;

/**
 * Created by IntelliJ IDEA.
 * User: hvst
 * Date: 2008-8-22
 * Time: 16:51:19
 * To change this template use File | Settings | File Templates.
 */
public class LeftOver extends HttpServlet {

     public void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{

         Double strLeftOver   = 0.0;
         String strSqlk        = "";

         Context ctx          = null;
         DataSource ds        = null;
         Connection conn      = null;
         Statement stmt       = null;
         ResultSet rs         = null;
         PrintWriter out      = null;
         String  strUserID = (String)request.getSession().getAttribute("userId");

         try {
             response.setContentType("text/html;charset=gb2312");
             Class.forName("com.mysql.jdbc.Driver");
             conn = DriverManager.getConnection("jdbc:mysql://localhost/bank?useUnicode=true&characterEncoding=gb2312", "root", "");
             stmt = conn.createStatement();
             strSqlk = " select leftover " +
                       " from `slimsy`" +
                       " where userid='" + strUserID + "'";
             rs = stmt.executeQuery(strSqlk);

             while(rs.next()){
                strLeftOver = rs.getDouble("leftover");
            }

             request.setAttribute("leaveMoney",strLeftOver);
             RequestDispatcher dispatcher = request.getRequestDispatcher("/jsp/leftover.jsp");
             dispatcher.forward(request,response);

         } catch (Exception e) {
             e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
         } finally {
             try {
                 if (rs != null) rs.close();
                 if(stmt != null) stmt.close();
                 if(conn != null) conn.close();
             } catch (SQLException e) {
                 e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
             }
         }
     }
}