计算机程序设计员三级考试第三题

import javax.swing.*; import java.awt.*; import java.awt.event.*; import java.sql.*; public class CarRentalSystem extends JFrame { private Connection connect() { try { return DriverManager.getConnection( "jdbc:mysql://localhost:3306/car_rental_system", "root", "123456"); } catch (SQLException e) { JOptionPane.showMessageDialog(this, "数据库连接失败: " + e.getMessage()); return null; } } public CarRentalSystem() { setTitle("汽车租赁信息管理系统"); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setSize(600, 400); setLocationRelativeTo(null); JTabbedPane tabbedPane = new JTabbedPane(); tabbedPane.addTab("汽车登记", createRegisterPanel()); tabbedPane.addTab("租赁管理", createRentPanel()); tabbedPane.addTab("归还管理", createReturnPanel()); tabbedPane.addTab("查询功能", createSearchPanel()); add(tabbedPane); setVisible(true); } private JPanel createRegisterPanel() { JPanel panel = new JPanel(new GridLayout(0, 2, 10, 10)); JTextField txtId = new JTextField(), txtBrand = new JTextField(), txtModel = new JTextField(), txtYear = new JTextField(), txtRent = new JTextField(); JButton btnSubmit = new JButton("提交"); panel.add(new JLabel("汽车编号:")); panel.add(txtId); panel.add(new JLabel("品牌:")); panel.add(txtBrand); panel.add(new JLabel("型号:")); panel.add(txtModel); panel.add(new JLabel("年份:")); panel.add(txtYear); panel.add(new JLabel("每日租金:")); panel.add(txtRent); panel.add(btnSubmit); btnSubmit.addActionListener(e -> { registerCar(txtId.getText(), txtBrand.getText(), txtModel.getText(), Integer.parseInt(txtYear.getText()), Double.parseDouble(txtRent.getText())); }); return panel; } private void registerCar(String id, String brand, String model, int year, double dailyRent) { String sql = "INSERT INTO cars (id, brand, model, year, daily_rent) VALUES (?, ?, ?, ?, ?)"; try (Connection conn = connect(); PreparedStatement pstmt = conn.prepareStatement(sql)) { pstmt.setString(1, id); pstmt.setString(2, brand); pstmt.setString(3, model); pstmt.setInt(4, year); pstmt.setDouble(5, dailyRent); pstmt.executeUpdate(); JOptionPane.showMessageDialog(this, "汽车信息登记成功"); } catch (SQLException e) { JOptionPane.showMessageDialog(this, "登记失败: " + e.getMessage()); } } private JPanel createRentPanel() { JPanel panel = new JPanel(new GridLayout(0, 2, 10, 10)); JTextField txtCarId = new JTextField(), txtName = new JTextField(), txtContact = new JTextField(), txtStartDate = new JTextField(); JButton btnRent = new JButton("租出"); panel.add(new JLabel("汽车编号:")); panel.add(txtCarId); panel.add(new JLabel("客户姓名:")); panel.add(txtName); panel.add(new JLabel("联系方式:")); panel.add(txtContact); panel.add(new JLabel("起租日期:")); panel.add(txtStartDate); panel.add(btnRent); btnRent.addActionListener(e -> { rentCar(txtCarId.getText(), txtName.getText(), txtContact.getText(), txtStartDate.getText()); }); return panel; } private void rentCar(String carId, String customerName, String contact, String startDate) { String sqlRent = "INSERT INTO rentals (car_id, customer_name, contact, start_date) VALUES (?, ?, ?, ?)"; String sqlUpdate = "UPDATE cars SET status = 'rented' WHERE id = ?"; try (Connection conn = connect(); PreparedStatement pstmtRent = conn.prepareStatement(sqlRent); PreparedStatement pstmtUpdate = conn.prepareStatement(sqlUpdate)) { // Start transaction conn.setAutoCommit(false); // Insert rental record pstmtRent.setString(1, carId); pstmtRent.setString(2, customerName); pstmtRent.setString(3, contact); pstmtRent.setDate(4, Date.valueOf(startDate)); pstmtRent.executeUpdate(); // Update car status pstmtUpdate.setString(1, carId); pstmtUpdate.executeUpdate(); // Commit transaction conn.commit(); JOptionPane.showMessageDialog(this, "汽车租出成功"); } catch (SQLException e) { JOptionPane.showMessageDialog(this, "租出失败: " + e.getMessage()); } } private JPanel createReturnPanel() { JPanel panel = new JPanel(new GridLayout(0, 2, 10, 10)); JTextField txtCarId = new JTextField(), txtEndDate = new JTextField(); JButton btnReturn = new JButton("归还"); panel.add(new JLabel("汽车编号:")); panel.add(txtCarId); panel.add(new JLabel("归还日期:")); panel.add(txtEndDate); panel.add(btnReturn); btnReturn.addActionListener(e -> { returnCar(txtCarId.getText(), txtEndDate.getText()); }); return panel; } private void returnCar(String carId, String endDate) { String sql = "UPDATE rentals SET end_date = ?, total_rent = (SELECT daily_rent FROM cars WHERE id = ?) * DATEDIFF(?, start_date) WHERE car_id = ? AND end_date IS NULL"; String sqlUpdate = "UPDATE cars SET status = 'available' WHERE id = ?"; try (Connection conn = connect(); PreparedStatement pstmt = conn.prepareStatement(sql); PreparedStatement pstmtUpdate = conn.prepareStatement(sqlUpdate)) { // Start transaction conn.setAutoCommit(false); // Update rental record pstmt.setDate(1, Date.valueOf(endDate)); pstmt.setString(2, carId); pstmt.setDate(3, Date.valueOf(endDate)); pstmt.setString(4, carId); pstmt.executeUpdate(); // Update car status pstmtUpdate.setString(1, carId); pstmtUpdate.executeUpdate(); // Commit transaction conn.commit(); JOptionPane.showMessageDialog(this, "汽车归还成功"); } catch (SQLException e) { JOptionPane.showMessageDialog(this, "归还失败: " + e.getMessage()); } } private JPanel createSearchPanel() { JPanel panel = new JPanel(new BorderLayout()); JTextField txtSearch = new JTextField(); JTextArea txtResults = new JTextArea(); txtResults.setEditable(false); JButton btnSearch = new JButton("搜索"); panel.add(txtSearch, BorderLayout.NORTH); panel.add(new JScrollPane(txtResults), BorderLayout.CENTER); panel.add(btnSearch, BorderLayout.SOUTH); btnSearch.addActionListener(e -> { search(txtSearch.getText(), txtResults); }); return panel; } private void search(String keyword, JTextArea txtResults) { String sql = "SELECT * FROM rentals INNER JOIN cars ON rentals.car_id = cars.id WHERE car_id = ? OR customer_name LIKE ?"; try (Connection conn = connect(); PreparedStatement pstmt = conn.prepareStatement(sql)) { pstmt.setString(1, keyword); pstmt.setString(2, "%" + keyword + "%"); ResultSet rs = pstmt.executeQuery(); StringBuilder results = new StringBuilder(); while (rs.next()) { results.append("Rental ID: ").append(rs.getInt("rental_id")).append("\n"); results.append("Car ID: ").append(rs.getString("car_id")).append("\n"); results.append("Customer Name: ").append(rs.getString("customer_name")).append("\n"); results.append("Contact: ").append(rs.getString("contact")).append("\n"); results.append("Start Date: ").append(rs.getDate("start_date")).append("\n"); results.append("End Date: ").append(rs.getDate("end_date")).append("\n"); results.append("Total Rent: ").append(rs.getDouble("total_rent")).append("\n\n"); } txtResults.setText(results.toString()); } catch (SQLException e) { JOptionPane.showMessageDialog(this, "查询失败: " + e.getMessage()); } } public static void main(String[] args) { SwingUtilities.invokeLater(() -> new CarRentalSystem()); } }