一个很简单的银行账户系统JSP+servlet

如果你是初次接触jsp和servlet，这个就是你的不二之选，里面没有无关的代码，有链接数据库的，JSP传递数据给servlet处理的，还有servlet控制页面跳转的，绝对不可多得啊

package edu.nju.bank.Account.servlets;

import java.io.IOException;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import edu.nju.bankAccount.beans.*;
import edu.nju.bankDB.*;

public class ShowBalance extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public ShowBalance（） {
		super（）;
	}

	/**
	 * Destruction of the servlet. 

	 */
	public void destroy（） {
		super.destroy（）; // Just puts “destroy“ string in log
		// Put your code here
	}

	public void doGet（HttpServletRequest request HttpServletResponse response）
			throws ServletException IOException {
		this.doPost（request response）;
	}

	/**
	 * The doPost method of the servlet. 

	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost（HttpServletRequest request HttpServletResponse response）
			throws ServletException IOException {

		response.setContentType（“text/html“）;
		String address = ““;
		String IDString = request.getParameter（“userid“）;
		BankCustomer bankCustomer = null;
		DBCon dbCon = new DBCon（）;
		Connection connection = dbCon.getConnection（）;
		PreparedStatement pStatement = null;
		ResultSet resultSet = null;
		String sqlString = “select * from useraccount where userid=‘“ + IDString + “‘“;
		try {
			pStatement = connection.prepareStatement（sqlString）;
			resultSet = pStatement.executeQuery（）;
			while（resultSet.next（））{
				bankCustomer = new BankCustomer（）;
				bankCustomer.setUserid（resultSet.getInt（1））;
				bankCustomer.setBalance（resultSet.getFloat（2））;
				bankCustomer.setUserNameString（resultSet.getString（3））;
			}
		} catch （Exception e） {
			address = “/showaccount/login.jsp“;
		}
		
		if （bankCustomer == null） {
			address = “/showaccount/UnknownCustomer.jsp“;
		}else if （bankCustomer.getBalance（）<0） {
			address = “/showaccount/NegativeBalance.jsp“;
			request.setAttribute（“badCustomer“ bankCustomer）;
		}else if （bankCustomer.getBalance（）>10000） {
			address = “/showaccount/HighBalance.jsp“;
			request.setAttribute（“highCustomer“ bankCustomer）;
		}else{
			address = “/showaccount/NormalBalance.jsp“;
			request.setAttribute（“normalCustomer“ bankCustomer）;
		}
		RequestDispatcher dispatcher =request.getRequestDispatcher（address）;
		dispatcher.forward（request response）;

	}

	/**
	 * Initialization of the servlet. 

	 *
	 * @throws ServletException if an error occurs
	 */
	public void init（） throws ServletException {

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----

     文件        768  2010-05-06 13:12  bankAccount\.classpath

     文件        306  2010-05-05 21:16  bankAccount\.mymetadata

     文件       1417  2010-05-06 09:04  bankAccount\.project

     文件        406  2010-05-05 21:16  bankAccount\.settings\.jsdtscope

     文件        334  2010-05-05 21:16  bankAccount\.settings\org.eclipse.jdt.core.prefs

     文件         49  2010-05-05 21:16  bankAccount\.settings\org.eclipse.wst.jsdt.ui.superType.container

     文件          6  2010-05-05 21:16  bankAccount\.settings\org.eclipse.wst.jsdt.ui.superType.name

     文件       3034  2010-06-05 18:14  bankAccount\src\edu\nju\bank\Account\servlets\ShowBalance.java

     文件        651  2010-05-06 13:16  bankAccount\src\edu\nju\bankAccount\beans\BankCustomer.java

     文件        593  2010-06-05 13:13  bankAccount\src\edu\nju\bankDB\DBCon.java

     文件      25451  2010-04-08 17:22  bankAccount\WebRoot\image\top.jpg

     文件         39  2010-05-05 21:16  bankAccount\WebRoot\meta-INF\MANIFEST.MF

     文件       1143  2010-05-06 12:38  bankAccount\WebRoot\showaccount\HighBalance.jsp

     文件       1904  2010-05-06 13:01  bankAccount\WebRoot\showaccount\login.jsp

     文件       1159  2010-05-06 12:34  bankAccount\WebRoot\showaccount\NegativeBalance.jsp

     文件       1094  2010-05-06 12:35  bankAccount\WebRoot\showaccount\NormalBalance.jsp

     文件       2474  2010-05-06 09:23  bankAccount\WebRoot\showaccount\Register.html

     文件        862  2010-05-06 12:36  bankAccount\WebRoot\showaccount\UnknownCustomer.jsp

     文件       3360  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bank\Account\servlets\ShowBalance.class

     文件       1060  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bankAccount\beans\BankCustomer.class

     文件       1017  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bankDB\DBCon.class

     文件        819  2010-05-06 12:59  bankAccount\WebRoot\WEB-INF\web.xml

     目录          0  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bank\Account\servlets

     目录          0  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bank\Account

     目录          0  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bankAccount\beans

     目录          0  2010-05-06 12:20  bankAccount\src\edu\nju\bank\Account\servlets

     目录          0  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bank

     目录          0  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bankAccount

     目录          0  2010-06-25 13:14  bankAccount\WebRoot\WEB-INF\classes\edu\nju\bankDB

     目录          0  2010-05-05 21:18  bankAccount\src\edu\nju\bank\Account

............此处省略22个文件信息