版本說明

1. 2015-07-02 第一版。

2. 2015-07-04 修復餘額變更錯誤問題（變數使用錯誤造成），增加修改商品數量功能，調整檢視結構，修改Unicode為中文，增加功能提示。

下面的程式碼為最新版本程式碼。

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Image;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import
 
 java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import
 
 javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.border.CompoundBorder;
import javax.swing.border.LineBorder;
import javax.swing.border.TitledBorder;
import javax.swing.JTabbedPane;
import
 
 java.awt.FlowLayout;

/**
 * 自動售貨機 功能說明：
 * <ol>
 * <li>點選圖片或圖片下方的購買複選框進行商品的選擇或取消選擇，商品數量小於等於0時無法選擇；</li>
 * <li>點選“投入一元”或“投入五元”按鈕模擬投入錢操作；</li>
 * <li>點選“購買”按鈕完成購買，當投入錢數少於購買商品需要的錢數時購買不成功，當系統零錢不夠找零時購買不成功；</li>
 * <li>點選“退款”按鈕完成退款；</li>
 * <li>點選“檢視”按鈕可以檢視所有商品的剩餘數量，顯示五秒後會關閉顯示；</li>
 * <li>點選“登入”按鈕彈出登入管理員需要的密碼輸入框，輸入ADMIN後可以進入管理員頁面，管理員頁面分為修改餘額和修改商品兩個標籤頁，修改餘額標籤頁可以檢視系統總餘額，系統一元數量和五元數量，同時可以手動更新一元和五元的數量，完成修改餘額操作；修改商品標籤頁可以檢視商品總數量和各個商品的分數量，同時可以手動修改每個商品的數量，完成修改商品數量操作。</li>
 * </ol>
 * <p>
 * <h4>注意在執行之前修改圖片路徑</h4>
 * 
 * @author th
 */
public class AutoSaleMachine extends JFrame {

    private static final long serialVersionUID = 6576104659382463412L;

    private static final String ADMIN = "ADMIN"; // 管理員密碼

    // 初始化所有商品的名字
    private static final String NAME_COKE = "可口可樂";
    private static final String NAME_FANTA = "芬達";
    private static final String NAME_RTEA = "紅茶";
    private static final String NAME_GTEA = "綠茶";

    // 初始化所有商品的價格
    private static final int PRICE_COKE = 3;
    private static final int PRICE_FANTA = 2;
    private static final int PRICE_RTEA = 4;
    private static final int PRICE_GTEA = 5;

    // 初始化所有商品的ID，沒有多少用
    private static final int ID_COKE = 1;
    private static final int ID_FANTA = 2;
    private static final int ID_RTEA = 3;
    private static final int ID_GTEA = 4;

    // 初始化所有商品數量
    private static int COUNT_COKE = 10;
    private static int COUNT_FANTA = 1;
    private static int COUNT_RTEA = 30;
    private static int COUNT_GTEA = 2;

    private String img_coke = "photos/coke.jpg";
    private String img_fanta = "photos/fanta.jpg";
    private String img_rtea = "photos/rtea.jpg";
    private String img_gtea = "photos/gtea.jpg";

    private int cokeCount;
    private int fantaCount;
    private int rteaCount;
    private int gteaCount;

    private int userMoneySum; // 使用者投入的錢數
    private int userOneCount; // 使用者一元計數
    private int userFiveCount; // 使用者五元計數
    private int sysMoneySum; // 系統的總錢數
    private int sysOneCount = 1; // 系統一元計數
    private int sysFiveCount = 20; // 系統五元計數
    private JTextField txt_UserMoney;
    private JButton btn_UserFive;
    private JButton btn_UserOne;

    private GoodPanel gp_coke;
    private GoodPanel gp_fanta;
    private GoodPanel gp_rtea;
    private GoodPanel gp_gtea;

    private JButton btn_Show;
    private JButton btn_Buy;
    private JButton btn_Cancle;
    private JButton btn_Admin;
    private JPanel panel_Admin;
    private JLabel lbl_SysMoneySum;
    private JTextField txt_SysSum;
    private JLabel lbl_SysOneSum;
    private JTextField txt_SysOne;
    private JLabel lbl_SysFiveSum;
    private JTextField txt_SysFive;
    private JButton btn_Save;
    private JButton btn_Logout;

    public AutoSaleMachine() {
        setTitle("自動售貨機");
        GridBagLayout gridBagLayout = new GridBagLayout();
        gridBagLayout.columnWidths = new int[] { 0, 0 };
        gridBagLayout.rowHeights = new int[] { 0, 0, 0, 0 };
        gridBagLayout.columnWeights = new double[] { 1.0, Double.MIN_VALUE };
        gridBagLayout.rowWeights = new double[] { 1.0, 0.0, 0.0,
                Double.MIN_VALUE };
        getContentPane().setLayout(gridBagLayout);

        JPanel panel_Good = new JPanel();
        GridBagConstraints gbc_panel_Good = new GridBagConstraints();
        gbc_panel_Good.insets = new Insets(0, 0, 5, 0);
        gbc_panel_Good.fill = GridBagConstraints.BOTH;
        gbc_panel_Good.gridx = 0;
        gbc_panel_Good.gridy = 0;
        getContentPane().add(panel_Good, gbc_panel_Good);
        GridBagLayout gbl_panel_Good = new GridBagLayout();
        gbl_panel_Good.columnWidths = new int[] { 230, 230, 0 };
        gbl_panel_Good.rowHeights = new int[] { 0, 0, 0 };
        gbl_panel_Good.columnWeights = new double[] { 0.5, 0.5,
                Double.MIN_VALUE };
        gbl_panel_Good.rowWeights = new double[] { 0.5, 0.5, Double.MIN_VALUE };
        panel_Good.setLayout(gbl_panel_Good);

        gp_coke = new GoodPanel(img_coke, PRICE_COKE, NAME_COKE, ID_COKE,
                COUNT_COKE);
        GridBagConstraints gbc_gp_coke = new GridBagConstraints();
        gbc_gp_coke.insets = new Insets(5, 5, 5, 5);
        gbc_gp_coke.fill = GridBagConstraints.BOTH;
        gbc_gp_coke.gridx = 0;
        gbc_gp_coke.gridy = 0;
        panel_Good.add(gp_coke, gbc_gp_coke);

        gp_fanta = new GoodPanel(img_fanta, PRICE_FANTA, NAME_FANTA, ID_FANTA,
                COUNT_FANTA);
        GridBagConstraints gbc_gp_fanta = new GridBagConstraints();
        gbc_gp_fanta.insets = new Insets(5, 5, 5, 5);
        gbc_gp_fanta.fill = GridBagConstraints.BOTH;
        gbc_gp_fanta.gridx = 1;
        gbc_gp_fanta.gridy = 0;
        panel_Good.add(gp_fanta, gbc_gp_fanta);

        gp_rtea = new GoodPanel(img_rtea, PRICE_RTEA, NAME_RTEA, ID_RTEA,
                COUNT_RTEA);
        GridBagConstraints gbc_gp_rtea = new GridBagConstraints();
        gbc_gp_rtea.insets = new Insets(5, 5, 5, 5);
        gbc_gp_rtea.fill = GridBagConstraints.BOTH;
        gbc_gp_rtea.gridx = 0;
        gbc_gp_rtea.gridy = 1;
        panel_Good.add(gp_rtea, gbc_gp_rtea);

        gp_gtea = new GoodPanel(img_gtea, PRICE_GTEA, NAME_GTEA, ID_GTEA,
                COUNT_GTEA);
        GridBagConstraints gbc_gp_gtea = new GridBagConstraints();
        gbc_gp_gtea.insets = new Insets(5, 5, 5, 5);
        gbc_gp_gtea.fill = GridBagConstraints.BOTH;
        gbc_gp_gtea.gridx = 1;
        gbc_gp_gtea.gridy = 1;
        panel_Good.add(gp_gtea, gbc_gp_gtea);

        JPanel panel_Btn = new JPanel();
        GridBagConstraints gbc_panel_Btn = new GridBagConstraints();
        gbc_panel_Btn.insets = new Insets(0, 0, 5, 0);
        gbc_panel_Btn.fill = GridBagConstraints.HORIZONTAL;
        gbc_panel_Btn.gridx = 0;
        gbc_panel_Btn.gridy = 1;
        getContentPane().add(panel_Btn, gbc_panel_Btn);
        GridBagLayout gbl_panel_Btn = new GridBagLayout();
        gbl_panel_Btn.columnWidths = new int[] { 0, 0, 0, 0, 0 };
        gbl_panel_Btn.rowHeights = new int[] { 0, 0, 0 };
        gbl_panel_Btn.columnWeights = new double[] { 0.25, 0.25, 0.25, 0.25,
                Double.MIN_VALUE };
        gbl_panel_Btn.rowWeights = new double[] { 0.0, 0.0, Double.MIN_VALUE };
        panel_Btn.setLayout(gbl_panel_Btn);

        JLabel lbl_UserMoney = new JLabel("投入金額（元）：");
        GridBagConstraints gbc_lbl_UserMoney = new GridBagConstraints();
        gbc_lbl_UserMoney.insets = new Insets(5, 5, 5, 5);
        gbc_lbl_UserMoney.gridx = 0;
        gbc_lbl_UserMoney.gridy = 0;
        panel_Btn.add(lbl_UserMoney, gbc_lbl_UserMoney);

        txt_UserMoney = new JTextField();
        txt_UserMoney.setEditable(false);
        GridBagConstraints gbc_txt_UserMoney = new GridBagConstraints();
        gbc_txt_UserMoney.insets = new Insets(5, 0, 5, 5);
        gbc_txt_UserMoney.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_UserMoney.gridx = 1;
        gbc_txt_UserMoney.gridy = 0;
        panel_Btn.add(txt_UserMoney, gbc_txt_UserMoney);
        txt_UserMoney.setColumns(10);

        btn_UserOne = new JButton("投入一元");
        GridBagConstraints gbc_btn_UserOne = new GridBagConstraints();
        gbc_btn_UserOne.insets = new Insets(5, 0, 5, 5);
        gbc_btn_UserOne.gridx = 2;
        gbc_btn_UserOne.gridy = 0;
        panel_Btn.add(btn_UserOne, gbc_btn_UserOne);
        btn_UserOne.addActionListener(handler);

        btn_Show = new JButton("檢視");
        btn_Show.setToolTipText("檢視自動售貨機中的商品數量，顯示五秒後關閉");
        GridBagConstraints gbc_btn_Show = new GridBagConstraints();
        gbc_btn_Show.insets = new Insets(0, 0, 5, 5);
        gbc_btn_Show.gridx = 0;
        gbc_btn_Show.gridy = 1;
        panel_Btn.add(btn_Show, gbc_btn_Show);
        btn_Show.addActionListener(handler);

        btn_Buy = new JButton("購買");
        GridBagConstraints gbc_btn_Buy = new GridBagConstraints();
        gbc_btn_Buy.insets = new Insets(0, 0, 5, 5);
        gbc_btn_Buy.gridx = 1;
        gbc_btn_Buy.gridy = 1;
        panel_Btn.add(btn_Buy, gbc_btn_Buy);
        btn_Buy.addActionListener(handler);

        btn_UserFive = new JButton("投入五元");
        GridBagConstraints gbc_btn_UserFive = new GridBagConstraints();
        gbc_btn_UserFive.insets = new Insets(5, 0, 5, 0);
        gbc_btn_UserFive.gridx = 3;
        gbc_btn_UserFive.gridy = 0;
        panel_Btn.add(btn_UserFive, gbc_btn_UserFive);
        btn_UserFive.addActionListener(handler);

        btn_Cancle = new JButton("取消");
        GridBagConstraints gbc_btn_Cancle = new GridBagConstraints();
        gbc_btn_Cancle.insets = new Insets(0, 0, 5, 5);
        gbc_btn_Cancle.gridx = 2;
        gbc_btn_Cancle.gridy = 1;
        panel_Btn.add(btn_Cancle, gbc_btn_Cancle);
        btn_Cancle.addActionListener(handler);

        btn_Admin = new JButton("登入");
        btn_Admin.setToolTipText("需要登入密碼，登入後可以修改系統餘額和商品數量。");
        GridBagConstraints gbc_btn_Admin = new GridBagConstraints();
        gbc_btn_Admin.insets = new Insets(0, 0, 5, 0);
        gbc_btn_Admin.gridx = 3;
        gbc_btn_Admin.gridy = 1;
        panel_Btn.add(btn_Admin, gbc_btn_Admin);
        btn_Admin.addActionListener(handler);

        panel_Admin = new JPanel();
        panel_Admin.setBorder(new TitledBorder(null, "管理員介面",
                TitledBorder.LEADING, TitledBorder.TOP, null, null));
        GridBagConstraints gbc_panel = new GridBagConstraints();
        gbc_panel.fill = GridBagConstraints.BOTH;
        gbc_panel.gridx = 0;
        gbc_panel.gridy = 2;
        getContentPane().add(panel_Admin, gbc_panel);
        panel_Admin.setLayout(new BorderLayout(0, 0));

        tabbedPane = new JTabbedPane(JTabbedPane.TOP);
        panel_Admin.add(tabbedPane, BorderLayout.NORTH);

        panel_AdminMoney = new JPanel();
        tabbedPane.addTab("修改餘額", null, panel_AdminMoney, null);
        GridBagLayout gbl_panel_AdminMoney = new GridBagLayout();
        gbl_panel_AdminMoney.columnWidths = new int[] { 0, 0, 0, 0, 0 };
        gbl_panel_AdminMoney.rowHeights = new int[] { 0, 0, 0, 0 };
        gbl_panel_AdminMoney.columnWeights = new double[] { 0.0, 0.5, 0.0, 0.5,
                Double.MIN_VALUE };
        gbl_panel_AdminMoney.rowWeights = new double[] { 0.0, 0.0, 0.0,
                Double.MIN_VALUE };
        panel_AdminMoney.setLayout(gbl_panel_AdminMoney);

        lbl_SysMoneySum = new JLabel("系統總餘額：");
        GridBagConstraints gbc_lbl_SysMoneySum = new GridBagConstraints();
        gbc_lbl_SysMoneySum.insets = new Insets(0, 0, 5, 5);
        gbc_lbl_SysMoneySum.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysMoneySum.gridx = 0;
        gbc_lbl_SysMoneySum.gridy = 0;
        panel_AdminMoney.add(lbl_SysMoneySum, gbc_lbl_SysMoneySum);

        txt_SysSum = new JTextField();
        txt_SysSum.setEditable(false);
        GridBagConstraints gbc_txt_SysSum = new GridBagConstraints();
        gbc_txt_SysSum.insets = new Insets(0, 0, 5, 5);
        gbc_txt_SysSum.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_SysSum.gridx = 1;
        gbc_txt_SysSum.gridy = 0;
        panel_AdminMoney.add(txt_SysSum, gbc_txt_SysSum);
        txt_SysSum.setColumns(10);

        lbl_SysOneSum = new JLabel("系統一元數量：");
        GridBagConstraints gbc_lbl_SysOneSum = new GridBagConstraints();
        gbc_lbl_SysOneSum.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysOneSum.insets = new Insets(0, 5, 5, 5);
        gbc_lbl_SysOneSum.gridx = 0;
        gbc_lbl_SysOneSum.gridy = 1;
        panel_AdminMoney.add(lbl_SysOneSum, gbc_lbl_SysOneSum);

        txt_SysOne = new JTextField();
        GridBagConstraints gbc_txt_SysOne = new GridBagConstraints();
        gbc_txt_SysOne.insets = new Insets(0, 0, 5, 5);
        gbc_txt_SysOne.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_SysOne.gridx = 1;
        gbc_txt_SysOne.gridy = 1;
        txt_SysOne.setToolTipText("可以輸入修改後的數量，點選儲存按鈕完成系統中一元數量的修改。");
        panel_AdminMoney.add(txt_SysOne, gbc_txt_SysOne);
        txt_SysOne.setColumns(10);

        lbl_SysFiveSum = new JLabel("系統五元數量：");
        GridBagConstraints gbc_lbl_SysFiveSum = new GridBagConstraints();
        gbc_lbl_SysFiveSum.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysFiveSum.insets = new Insets(0, 5, 0, 5);
        gbc_lbl_SysFiveSum.gridx = 0;
        gbc_lbl_SysFiveSum.gridy = 2;
        panel_AdminMoney.add(lbl_SysFiveSum, gbc_lbl_SysFiveSum);

        txt_SysFive = new JTextField();
        GridBagConstraints gbc_txt_SysFive = new GridBagConstraints();
        gbc_txt_SysFive.insets = new Insets(0, 0, 0, 5);
        gbc_txt_SysFive.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_SysFive.gridx = 1;
        gbc_txt_SysFive.gridy = 2;
        txt_SysFive.setToolTipText("可以輸入修改後的數量，點選儲存按鈕完成系統中一元數量的修改。");
        panel_AdminMoney.add(txt_SysFive, gbc_txt_SysFive);
        txt_SysFive.setColumns(10);

        panel_AdminGood = new JPanel();
        tabbedPane.addTab("\u4FEE\u6539\u5546\u54C1", null, panel_AdminGood,
                null);
        GridBagLayout gbl_panel_AdminGood = new GridBagLayout();
        gbl_panel_AdminGood.columnWidths = new int[] { 0, 0, 0, 0, 0 };
        gbl_panel_AdminGood.rowHeights = new int[] { 0, 0, 0, 0 };
        gbl_panel_AdminGood.columnWeights = new double[] { 0.0, 0.5, 0.0, 0.5,
                Double.MIN_VALUE };
        gbl_panel_AdminGood.rowWeights = new double[] { 0.0, 0.0, 0.0,
                Double.MIN_VALUE };
        panel_AdminGood.setLayout(gbl_panel_AdminGood);

        lbl_SysGood = new JLabel("系統總商品數量：");
        GridBagConstraints gbc_lbl_SysGood = new GridBagConstraints();
        gbc_lbl_SysGood.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysGood.insets = new Insets(0, 0, 5, 5);
        gbc_lbl_SysGood.gridx = 0;
        gbc_lbl_SysGood.gridy = 0;
        panel_AdminGood.add(lbl_SysGood, gbc_lbl_SysGood);

        txt_SysGood = new JTextField();
        txt_SysGood.setEditable(false);
        GridBagConstraints gbc_txt_SysGood = new GridBagConstraints();
        gbc_txt_SysGood.insets = new Insets(0, 0, 5, 5);
        gbc_txt_SysGood.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_SysGood.gridx = 1;
        gbc_txt_SysGood.gridy = 0;
        panel_AdminGood.add(txt_SysGood, gbc_txt_SysGood);
        txt_SysGood.setColumns(10);

        lbl_SysCoke = new JLabel("可口可樂數量：");
        GridBagConstraints gbc_lbl_SysCoke = new GridBagConstraints();
        gbc_lbl_SysCoke.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysCoke.insets = new Insets(0, 5, 5, 0);
        gbc_lbl_SysCoke.gridx = 0;
        gbc_lbl_SysCoke.gridy = 1;
        panel_AdminGood.add(lbl_SysCoke, gbc_lbl_SysCoke);

        txt_CountCoke = new JTextField();
        GridBagConstraints gbc_txt_CountCoke = new GridBagConstraints();
        gbc_txt_CountCoke.insets = new Insets(0, 0, 5, 5);
        gbc_txt_CountCoke.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_CountCoke.gridx = 1;
        gbc_txt_CountCoke.gridy = 1;
        panel_AdminGood.add(txt_CountCoke, gbc_txt_CountCoke);
        txt_CountCoke.setColumns(10);
        txt_CountCoke.setToolTipText("可以輸入修改後的數量，點選儲存按鈕完成系統中可口可樂數量的修改。");

        lbl_SysFanta = new JLabel("芬達數量：");
        GridBagConstraints gbc_lbl_SysFanta = new GridBagConstraints();
        gbc_lbl_SysFanta.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysFanta.insets = new Insets(0, 5, 5, 0);
        gbc_lbl_SysFanta.gridx = 2;
        gbc_lbl_SysFanta.gridy = 1;
        panel_AdminGood.add(lbl_SysFanta, gbc_lbl_SysFanta);

        txt_CountFanta = new JTextField();
        GridBagConstraints gbc_txt_CountFanta = new GridBagConstraints();
        gbc_txt_CountFanta.insets = new Insets(0, 0, 5, 0);
        gbc_txt_CountFanta.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_CountFanta.gridx = 3;
        gbc_txt_CountFanta.gridy = 1;
        panel_AdminGood.add(txt_CountFanta, gbc_txt_CountFanta);
        txt_CountFanta.setColumns(10);
        txt_CountFanta.setToolTipText("可以輸入修改後的數量，點選儲存按鈕完成系統中芬達數量的修改。");

        lbl_SysRtea = new JLabel("紅茶數量：");
        GridBagConstraints gbc_lbl_SysRtea = new GridBagConstraints();
        gbc_lbl_SysRtea.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysRtea.insets = new Insets(0, 5, 5, 0);
        gbc_lbl_SysRtea.gridx = 0;
        gbc_lbl_SysRtea.gridy = 2;
        panel_AdminGood.add(lbl_SysRtea, gbc_lbl_SysRtea);

        txt_CountRtea = new JTextField();
        GridBagConstraints gbc_txt_CountRtea = new GridBagConstraints();
        gbc_txt_CountRtea.insets = new Insets(0, 0, 5, 5);
        gbc_txt_CountRtea.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_CountRtea.gridx = 1;
        gbc_txt_CountRtea.gridy = 2;
        panel_AdminGood.add(txt_CountRtea, gbc_txt_CountRtea);
        txt_CountRtea.setColumns(10);
        txt_CountRtea.setToolTipText("可以輸入修改後的數量，點選儲存按鈕完成系統中紅茶數量的修改。");

        lbl_SysGtea = new JLabel("綠茶數量：");
        GridBagConstraints gbc_lbl_SysGtea = new GridBagConstraints();
        gbc_lbl_SysGtea.anchor = GridBagConstraints.EAST;
        gbc_lbl_SysGtea.insets = new Insets(0, 5, 5, 0);
        gbc_lbl_SysGtea.gridx = 2;
        gbc_lbl_SysGtea.gridy = 2;
        panel_AdminGood.add(lbl_SysGtea, gbc_lbl_SysGtea);

        txt_CountGtea = new JTextField();
        GridBagConstraints gbc_txt_CountGtea = new GridBagConstraints();
        gbc_txt_CountGtea.insets = new Insets(0, 0, 5, 0);
        gbc_txt_CountGtea.fill = GridBagConstraints.HORIZONTAL;
        gbc_txt_CountGtea.gridx = 3;
        gbc_txt_CountGtea.gridy = 2;
        panel_AdminGood.add(txt_CountGtea, gbc_txt_CountGtea);
        txt_CountGtea.setColumns(10);
        txt_CountGtea.setToolTipText("可以輸入修改後的數量，點選儲存按鈕完成系統中綠茶數量的修改。");

        panel_BtnAdmin = new JPanel();
        FlowLayout fl_panel_BtnAdmin = (FlowLayout) panel_BtnAdmin.getLayout();
        fl_panel_BtnAdmin.setHgap(35);
        btn_Save = new JButton("儲存");
        panel_BtnAdmin.add(btn_Save);
        btn_Save.addActionListener(handler);

        btn_Logout = new JButton("退出");
        panel_BtnAdmin.add(btn_Logout);
        panel_Admin.add(panel_BtnAdmin, BorderLayout.SOUTH);

        btn_Logout.addActionListener(handler);
        panel_Admin.setVisible(false);

    }

    /**
     * 響應按鈕事件
     */
    private ActionListener handler = new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            if (e.getSource() == btn_UserOne) {
                userOneCount++;
                updateUserMoney();
            } else if (e.getSource() == btn_UserFive) {
                userFiveCount++;
                updateUserMoney();
            } else if (e.getSource() == btn_Buy) {
                // 購買
                // 獲取購買的商品總價，如果總價大於輸入的錢數，提示使用者繼續投入錢
                int needSum = getGoodSum();
                if (needSum == 0) {
                    JOptionPane.showMessageDialog(null,
                            "購買失敗，您沒有選擇任何商品，請選擇需要的商品。");
                    return;
                } else if (needSum > userMoneySum) {
                    JOptionPane.showMessageDialog(null, "投入的金額小於需要購買商品的總價，請再投入"
                            + (needSum - userMoneySum) + "元或取消一些商品。");
                    reinitGoodCount();
                    return;
                } else {
                    // 計算需要找零的錢數
                    int remain = userMoneySum - needSum;
                    int remainFiveCount = remain / 5;
                    int remainOneCount = remain % 5;
                    // 修改系統錢數和計數
                    int sysRemain = sysOneCount + userOneCount - remainOneCount;
                    if (sysRemain < 0) {
                        JOptionPane.showMessageDialog(null,
                                "抱歉，系統中沒有足夠的零錢，請修改夠買商品或退款後使用零錢購買。");
                        return;
                    }
                    sysOneCount = sysRemain;
                    sysFiveCount = sysFiveCount + userFiveCount
                            - remainFiveCount;
                    sysMoneySum = sysOneCount + sysFiveCount * 5;

                    // 修改商品的總數
                    updateGoodCount();
                    // 輸出購買的商品和找零的錢數
                    String result = getBuyResult(remain);
                    JOptionPane.showMessageDialog(null, result);
                    // 設定初始狀態
                    reinit();
                    pnlAdminUpdate();
                }
            } else if (e.getSource() == btn_Cancle) {
                // 退款
                updateUserMoney();
                if (userMoneySum > 0) {
                    String remainResult = getRemianResult();
                    JOptionPane.showMessageDialog(null, remainResult);
                    reinit();
                } else {
                    JOptionPane.showMessageDialog(null, "您投入的錢數為0，無法進行退款操作。");
                }
            } else if (e.getSource() == btn_Show) {
                // 顯示剩餘商品數目
                showGoodCount();
            } else if (e.getSource() == btn_Admin) {
                String input = JOptionPane.showInputDialog("請輸入管理員密碼，區分大小寫。");

                if (ADMIN.equals(input)) {
                    // 登入成功，顯示管理員面板
                    pnlAdminUpdate();
                    panel_Admin.setVisible(true);
                    repaint();
                } else {
                    JOptionPane.showMessageDialog(null, "您輸入的密碼錯誤，無法進入管理員頁面。");
                }
            } else if (e.getSource() == btn_Save) {
                String oneStr = txt_SysOne.getText();
                int one = Integer.parseInt(oneStr);
                String fiveStr = txt_SysFive.getText();
                int five = Integer.parseInt(fiveStr);
                sysOneCount = one;
                sysFiveCount = five;
                sysMoneySum = sysOneCount + sysFiveCount * 5;
                txt_SysSum.setText(sysMoneySum + "");
                String cokeStr = txt_CountCoke.getText();
                COUNT_COKE = Integer.parseInt(cokeStr);
                String fantaStr = txt_CountFanta.getText();
                COUNT_FANTA = Integer.parseInt(fantaStr);
                String rteaStr = txt_CountRtea.getText();
                COUNT_RTEA = Integer.parseInt(rteaStr);
                String gteaStr = txt_CountGtea.getText();
                COUNT_GTEA = Integer.parseInt(gteaStr);
                int sysGoodSum = COUNT_COKE + COUNT_FANTA + COUNT_RTEA
                        + COUNT_GTEA;
                pnlAdminUpdate();
                JOptionPane.showMessageDialog(null, "修改成功，系統中的總餘額為："
                        + sysMoneySum + "元；總商品數量為：" + sysGoodSum + "。");
            } else if (e.getSource() == btn_Logout) {
                panel_Admin.setVisible(false);
                repaint();
            }
        }

    };
    private JLabel lbl_SysGood;
    private JTextField txt_SysGood;
    private JLabel lbl_SysCoke;
    private JTextField txt_CountCoke;
    private JLabel lbl_SysFanta;
    private JTextField txt_CountFanta;
    private JLabel lbl_SysRtea;
    private JTextField txt_CountRtea;
    private JLabel lbl_SysGtea;
    private JTextField txt_CountGtea;
    private JTabbedPane tabbedPane;
    private JPanel panel_AdminMoney;
    private JPanel panel_AdminGood;
    private JPanel panel_BtnAdmin;

    /**
     * 更新管理員面板資訊
     */
    private void pnlAdminUpdate() {
        txt_SysOne.setText(sysOneCount + "");
        txt_SysFive.setText(sysFiveCount + "");
        txt_SysSum.setText((sysOneCount + sysFiveCount * 5) + "");

        txt_CountCoke.setText(COUNT_COKE + "");
        txt_CountFanta.setText(COUNT_FANTA + "");
        txt_CountRtea.setText(COUNT_RTEA + "");
        txt_CountGtea.setText(COUNT_GTEA + "");
        txt_SysGood
                .setText((COUNT_COKE + COUNT_FANTA + COUNT_RTEA + COUNT_GTEA)
                        + "");

        gp_coke.setGoodCount(COUNT_COKE);
        gp_fanta.setGoodCount(COUNT_FANTA);
        gp_rtea.setGoodCount(COUNT_RTEA);
        gp_gtea.setGoodCount(COUNT_GTEA);
    }

    /**
     * 顯示商品數量
     */
    protected void showGoodCount() {
        gp_coke.showRemain();
        gp_fanta.showRemain();
        gp_rtea.showRemain();
        gp_gtea.showRemain();
    }

    /**
     * 獲取退款結果
     * 
     * @return
     */
    protected String getRemianResult() {
        StringBuffer sb = new StringBuffer();
        sb.append("退款成功。您取回");
        if (userOneCount > 0) {
            sb.append(userOneCount).append("個一元硬幣；");
        }

        if (userFiveCount > 0) {
            sb.append(userFiveCount).append("張五元紙幣；");
        }

        return sb.toString();
    }

    /**
     * 獲取購買的商品描述
     * 
     * @param remain
     * @return
     */
    protected String getBuyResult(int remain) {
        StringBuffer sb = new StringBuffer();
        sb.append("購買成功。您購買了");
        if (cokeCount > 0) {
            sb.append(cokeCount).append("瓶").append(NAME_COKE).append("；");
        }
        if (fantaCount > 0) {
            sb.append(fantaCount).append("瓶").append(NAME_FANTA).append("；");
        }
        if (rteaCount > 0) {
            sb.append(rteaCount).append("瓶").append(NAME_RTEA).append("；");
        }
        if (gteaCount > 0) {
            sb.append(gteaCount).append("瓶").append(NAME_GTEA).append("；");
        }
        if (remain >= 0) {
            sb.append("並找您" + remain + "元。");
        }
        return sb.toString();
    }

    /**
     * 更新商品數量
     */
    protected void updateGoodCount() {
        if (cokeCount > 0) {
            COUNT_COKE -= cokeCount;
            gp_coke.setGoodCount(COUNT_COKE);
            gp_coke.reInit();
        }
        if (fantaCount > 0) {
            COUNT_FANTA -= fantaCount;
            gp_fanta.setGoodCount(COUNT_FANTA);
            gp_fanta.reInit();
        }
        if (rteaCount > 0) {
            COUNT_RTEA -= rteaCount;
            gp_rtea.setGoodCount(COUNT_RTEA);
            gp_rtea.reInit();
        }
        if (gteaCount > 0) {
            COUNT_GTEA -= gteaCount;
            gp_gtea.setGoodCount(COUNT_GTEA);
            gp_gtea.reInit();
        }
    }

    /**
     * 設定商品選中數為0，並初始化投入錢數等於0；
     */
    protected void reinit() {
        reinitGoodCount();
        userOneCount = 0;
        userFiveCount = 0;
        userMoneySum = 0;
        txt_UserMoney.setText(0 + "");
    }

    /**
     * 重新設定商品的選擇數量為0
     */
    protected void reinitGoodCount() {
        cokeCount = 0;
        fantaCount = 0;
        rteaCount = 0;
        gteaCount = 0;
    }

    /**
     * 獲取購買商品需要的總錢數
     * 
     * @return
     */
    protected int getGoodSum() {
        int sum = 0;
        if (gp_coke.isSelected()) {
            cokeCount++;
            sum += cokeCount * PRICE_COKE;
        }
        if (gp_fanta.isSelected()) {
            fantaCount++;
            sum += fantaCount * PRICE_FANTA;
        }
        if (gp_rtea.isSelected()) {
            rteaCount++;
            sum += rteaCount * PRICE_RTEA;
        }
        if (gp_gtea.isSelected()) {
            gteaCount++;
            sum += gteaCount * PRICE_GTEA;
        }
        return sum;
    }

    /**
     * 更新使用者投入的錢數
     */
    protected void updateUserMoney() {
        userMoneySum = (userOneCount + userFiveCount * 5);
        txt_UserMoney.setText(userMoneySum + "");
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                AutoSaleMachine asm = new AutoSaleMachine();
                asm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                asm.setSize(500, 600);
                asm.setResizable(false);
                asm.setLocationRelativeTo(null);
                asm.setVisible(true);
            }
        });
    }
}

/**
 * @author th 商品面板，包含商品的圖片和名稱，以及是否選中的複選框
 */
class GoodPanel extends JPanel {

    /**
     * 
     */
    private static final long serialVersionUID = 4364216395712746083L;
    private static final String MONEY_UNIT = "元";
    private static final String TIP = "單擊圖片可以選擇購買或者取消購買";

    private String picPath;
    private String name;
    private JTextField txt_Price;
    private int price;
    private JLabel lbl_Pic;
    private JCheckBox cbox_Select;
    private int goodId;
    private int goodCount;
    private JLabel lbl_Remain;
    private JTextField txt_Remain;

    GoodPanel(String picPath, int price, String name, int goodId, int goodCount) {
        this.picPath = picPath;
        this.price = price;
        this.name = name;
        this.goodId = goodId;
        this.goodCount = goodCount;
        this.setBorder(new CompoundBorder(null, new LineBorder(new Color(255,
                0, 0), 2)));
        this.setLayout(new BorderLayout(0, 0));
        lbl_Pic = new JLabel();
        this.add(lbl_Pic, BorderLayout.CENTER);
        lbl_Pic.setToolTipText(TIP);
        // 單擊圖片可以選擇購買或者取消購買；
        lbl_Pic.addMouseListener(mouseAdapter);

        JPanel panel_Prop = new JPanel();
        this.add(panel_Prop, BorderLayout.SOUTH);

        JLabel lbl_Name = new JLabel(this.name);
        panel_Prop.add(lbl_Name);

        txt_Price = new JTextField();
        txt_Price.setEditable(false);
        panel_Prop.add(txt_Price);
        txt_Price.setColumns(2);
        txt_Price.setText(this.price + MONEY_UNIT);

        cbox_Select = new JCheckBox("購買");
        if (this.goodCount <= 0) {
            cbox_Select.setSelected(false);
        }
        panel_Prop.add(cbox_Select);

        lbl_Remain = new JLabel("剩餘：");
        panel_Prop.add(lbl_Remain);
        txt_Remain = new JTextField();
        txt_Remain.setEditable(false);
        panel_Prop.add(txt_Remain);
        txt_Remain.setColumns(2);
        lbl_Remain.setVisible(false);
        txt_Remain.setVisible(false);
        initPic();
    }

    /**
     * 圖片的響應事件
     */
    MouseAdapter mouseAdapter = new MouseAdapter() {
        @Override
        public void mouseClicked(MouseEvent e) {
            if (goodCount > 0)
                cbox_Select.setSelected(!cbox_Select.isSelected());
        }
    };

    /**
     * 設定商品數量
     * 
     * @param goodCount
     */
    public void setGoodCount(int goodCount) {
        this.goodCount = goodCount;
        if (this.goodCount <= 0) {
            cbox_Select.setEnabled(false);
        } else {