银行项目代码参考，这个可以帮助大家学习Java

package com.jxd.bank.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Scanner; import util.DBUtil; import com.jxd.bank.entity.BankAccount; import com.jxd.bank.entity.Record; public class BankAccountDaoImpl implements BankAccountDao { private static Scanner input = new Scanner(System.in); private static List<Map<BankAccount,Record>> list = new ArrayList<Map<BankAccount,Record>>(); private static BankAccount bac = new BankAccount(); private static Record r = new Record(); private static Map<BankAccount,Record> map = new HashMap<BankAccount, Record>(); private static Connection conn = null; private static PreparedStatement pst = null; private static ResultSet rs = null; /** * 开户 */ public BankAccount openAccount() { System.out.println("欢迎您开办新账户！请根据系统提示输入！\n"); System.out.println("请输入姓名："); String name = input.next(); System.out.println("请输入密码："); String pwd = input.next(); System.out.println("请输入初始余额"); double balance = input.nextInt(); System.out.println("请稍后，正在开户中……"); System.out.println("---------------------------"); try { conn = DBUtil.getConnection(); String sql = "insert into bankaccount(cardid,customername,password,oldpassword,balance，opendate) " + "values(seq_bankaccount.nextval,?,?,?,?,sysdate)"; pst = conn.prepareStatement(sql); pst.setString(1, name); pst.setString(2, pwd); pst.setString(3, pwd); pst.setDouble(4, balance); pst.executeUpdate(); String sql1 = "select * from bankaccount where customername = ? and password = ? order by cardid desc"; pst = conn.prepareStatement(sql1); pst.setString(1, name); pst.setString(2, pwd); rs = pst.executeQuery(); if (rs.next()) { String sql2 = "insert into record(id,cardid,transtype,transmoney,transdate) " + "values(seq_record.nextval,?,'1',?,sysdate)"; pst = conn.prepareStatement(sql2); pst.setInt(1, rs.getInt("cardid")); pst.setDouble(2, rs.getDouble("balance")); pst.executeUpdate(); r.setCardid(rs.getInt("cardid")); r.setTranstype("1"); r.setDate(rs.getString("opendate")); r.setTransmoney(rs.getDouble("balance")); bac.setCardid(rs.getInt("cardid")); bac.setCustomername(name); bac.setPassword(pwd); bac.setOldpassword(pwd); bac.setBalance(balance); bac.setDate(rs.getDate("opendate") + " " + rs.getTime("opendate")); map.put(bac, r); list.add(map); } else { System.out.println("密码长度过长,开户失败"); } System.out.println("---------------------------"); } catch (SQLException e) { e.printStackTrace(); } finally { DBUtil.closeAll(conn, pst, rs); } return bac; } /** * 取款 */ public List<Record> takeMoney() { System.out.println("欢迎来办理取款业务！请根据提示输入！"); System.out.println("请输入账号："); int cardid = input.nextInt(); System.out.println("请输入密码，有3次输入机会"); try { conn = DBUtil.getConnection(); for (int i = 0; i < 3; i++) { String pwd = input.next(); String sql = "select * from bankaccount where cardid = ? and password = ?"; pst = conn.prepareStatement(sql); pst.setInt(1, cardid); pst.setString(2, pwd); rs = pst.executeQuery(); if (rs.next()) { System.out.println("请输入取款金额："); double balance = input.nextDouble(); if (balance <= rs.getDouble("balance")) { System.out.println("请稍后，正在取款中……"); System.out .println("---------------------------------------"); String sql1 = "update bankaccount set balance = balance - ? where cardid = ?"; pst = conn.prepareStatement(sql1); pst.setDouble(1, balance); pst.setInt(2, cardid); pst.executeUpdate(); pst = conn.prepareStatement(sql); pst.setInt(1, cardid); pst.setString(2, pwd); rs = pst.executeQuery(); if (rs.next()) { System.out.println("恭喜你取款成功！"); System.out.println("您的余额是:" + rs.getDouble("balance")); } String sql2 = "insert into record(id,cardid,transtype,transmoney,transdate) " + "values(seq_record.nextval,?,'3',?,sysdate)"; pst = conn.prepareStatement(sql2); pst.setInt(1, cardid); pst.setDouble(2, balance); pst.executeUpdate(); String sql3 = "select * from record where cardid = ? and transmoney = ? and transtype = '3' " + "order by id desc"; pst = conn.prepareStatement(sql3); pst.setInt(1, cardid); pst.setDouble(2, balance); rs = pst.executeQuery(); if (rs.next()) { System.out.println("您的存款日期：" + rs.getString("transdate")); r.setCardid(rs.getInt("cardid")); r.setTranstype("3"); r.setDate(rs.getString("transdate")); r.setTransmoney(rs.getDouble("transmoney")); list.add(r); } break; } else { System.out.println("余额不足！！"); } } else { System.out.println("密码错误，请重新输入,还有" + (2 - i) + "次机会"); } } } catch (SQLException e) { e.printStackTrace(); } finally { DBUtil.closeAll(conn, pst, rs); } return list; } /** * 存款 */ public List<Record> saveMoney() { System.out.println("欢迎您来办理存款业务！请根据提示输入！"); System.out.println("请输入账号："); int cardid = input.nextInt(); System.out.println("请输入存款的金额："); double balance = input.nextDouble(); System.out.println("请稍后，正在存款中……"); System.out.println("---------------------------------"); try { conn = DBUtil.getConnection(); String sql = "select * from bankaccount where cardid = ?"; pst = conn.prepareStatement(sql); pst.setInt(1, cardid); rs = pst.executeQuery(); if (rs.next()) { String sql1 = "update bankaccount set balance = balance + ? where cardid = ?"; pst = conn.prepareStatement(sql1); pst.setDouble(1, balance); pst.setInt(2, cardid); pst.executeUpdate(); pst = conn.prepareStatement(sql); pst.setInt(1, cardid); rs = pst.executeQuery(); if (rs.next()) { System.out.println("恭喜你存款成功！"); System.out.println("您的存款金额是:" + balance); System.out.println("您的余额是:" + rs.getDouble("balance")); String sql2 = "insert into record(id,cardid,transtype,transmoney,transdate) " + "values(seq_record.nextval,?,'2',?,sysdate)"; pst = conn.prepareStatement(sql2); pst.setInt(1, cardid); pst.setDouble(2, balance); pst.executeUpdate(); String sql3 = "select * from record where cardid = ? and transmoney = ? and transtype = '2' " + "order by id desc"; pst = conn.prepareStatement(sql3); pst.setInt(1, cardid); pst.setDouble(2, balance); rs = pst.executeQuery(); if (rs.next()) { System.out.println("您的存款日期：" + rs.getString("transdate")); r.setCardid(rs.getInt("cardid")); r.setTranstype("2"); r.setDate(rs.getString("transdate")); r.setTransmoney(rs.getDouble("transmoney")); list.add(r); } } } else { System.out.println("卡号不存在"); } System.out.println("---------------------------------"); } catch (SQLException e) { e.printStackTrace(); } finally { DBUtil.closeAll(conn, pst, rs); } return list; } /** * 查询 */ public List<Record> queryMoney() { String type = null; System.out.println("欢迎您来查看账户信息！请根据提示输入！"); System.out.println("请输入账号:"); int cardid = input.nextInt(); System.out.println("请输入�