Dino`s Note

參考答案
import java.awt.*;
import java.awt.event.*;
import java.io.*;
public class JDD02 extends Frame implements ItemListener
{
BufferedWriter bw = null;
BufferedReader br = null;
//護士名字
String name[] =new String[4];
String weekDay[] = {"週一","週二","週三","週四","週五"};
//Panel pn1 包含了 Panel pn1a 及 Panel pn1b
Panel pn1 = new Panel();
//pn1a 用來放排班表
Panel pn1a = new Panel();
Choice chAM[] = new Choice[5]; //週一至週五早班
Choice chPM[] = new Choice[5]; //週一至週五晚班
Choice chNigh[] = new Choice[5]; //週一至週五夜班
//pn1b 放的是每位護士的班次統計表
Panel pn1b = new Panel();
Label lname[] = new Label[4]; //顯示每位護士名字
int AM[] = new int[4]; //每一位護士早班次數
int PM[] = new int[4]; //每一位護士晚班次數
int Nigh[] = new int[4]; //每一位護士夜班次數
Label lbAM[] = new Label[4]; //顯示每一位護士早班次數
Label lbPM[] = new Label[4]; //顯示每一位護士晚班次數
Label lbNigh[] = new Label[4]; //顯示每一位護士夜班次數
//pn3 是最下方的按鈕區
Panel pn3 = new Panel();
Button b1 = new Button("輸出");
Button b2 = new Button("離開");
public JDD02()
{
super("急診科護士排班表");
addWindowListener(new WinListener());
}
public static void main(String[] args)
{
JDD02 JD02 = new JDD02();
JD02.setup();
JD02.setSize(400,300);
JD02.setVisible(true);
}
void setup()
{
//請將護士的名單讀入
try{
br = new BufferedReader(new FileReader("list.txt"));
int i=0;
while(br.ready()){
name[i++] = br.readLine().trim();
}
br.close();
}catch(Exception ex)
{
ex.printStackTrace();
}
setpn1();
setpn3();
add(pn1);
add(pn3,BorderLayout.SOUTH);
}
//設定排班表內容
void setpn1()
{
pn1a.setLayout(new GridLayout(4,0));
pn1a.add(new Label(" "));
pn1a.add(new Label(weekDay[0]));
pn1a.add(new Label(weekDay[1]));
pn1a.add(new Label(weekDay[2]));
pn1a.add(new Label(weekDay[3]));
pn1a.add(new Label(weekDay[4]));
pn1a.add(new Label("早班"));
for(int h=0; h<chAM.length; h++)
{
chAM[h] = new Choice();
chPM[h] = new Choice();
chNigh[h] = new Choice(); //週一至週五夜班
//請將名單放入下拉式選單
for(int i=0;i<name.length;i++)
{
chAM[h].add(name[i]);
chPM[h].add(name[i]);
chNigh[h].add(name[i]);
}
chAM[h].addItemListener(this);
chPM[h].addItemListener(this);
chNigh[h].addItemListener(this);
}
pn1a.add(chAM[0]);
pn1a.add(chAM[1]);
pn1a.add(chAM[2]);
pn1a.add(chAM[3]);
pn1a.add(chAM[4]);
pn1a.add(new Label("晚班"));
pn1a.add(chPM[0]);
pn1a.add(chPM[1]);
pn1a.add(chPM[2]);
pn1a.add(chPM[3]);
pn1a.add(chPM[4]);
pn1a.add(new Label("夜班"));
pn1a.add(chNigh[0]);
pn1a.add(chNigh[1]);
pn1a.add(chNigh[2]);
pn1a.add(chNigh[3]);
pn1a.add(chNigh[4]);
//設定班別統計表
pn1b.setLayout(new GridLayout(4,4));
for(int a=0; a<lname.length; a++)
{
lname[a] = new Label(name[a]);
}
pn1b.add(new Label(" "));
pn1b.add(lname[0]);
pn1b.add(lname[1]);
pn1b.add(lname[2]);
pn1b.add(lname[3]);
pn1b.add(new Label("早班"));
lbAM[0] = new Label("");
lbAM[1] = new Label("");
lbAM[2] = new Label("");
lbAM[3] = new Label("");
pn1b.add(lbAM[0]);
pn1b.add(lbAM[1]);
pn1b.add(lbAM[2]);
pn1b.add(lbAM[3]);
pn1b.add(new Label("晚班"));
lbPM[0] = new Label("");
lbPM[1] = new Label("");
lbPM[2] = new Label("");
lbPM[3] = new Label("");
pn1b.add(lbPM[0]);
pn1b.add(lbPM[1]);
pn1b.add(lbPM[2]);
pn1b.add(lbPM[3]);
pn1b.add(new Label("夜班"));
lbNigh[0] = new Label("");
lbNigh[1] = new Label("");
lbNigh[2] = new Label("");
lbNigh[3] = new Label("");
pn1b.add(lbNigh[0]);
pn1b.add(lbNigh[1]);
pn1b.add(lbNigh[2]);
pn1b.add(lbNigh[3]);
pn1.setLayout(new GridLayout(0,1));
pn1.add(pn1a);
pn1.add(pn1b);
}
void setpn3()
{
b1.addActionListener(new act());
pn3.add(b1);
b2.addActionListener(new act());
pn3.add(b2);
}
//對Item的變動作出即時反應
public void itemStateChanged(ItemEvent e)
{
//先將資料清空
for(int i=0; i<AM.length; i++)
{
AM[i] =0;
PM[i] =0;
Nigh[i] = 0;
}
//請計算每一位護士早班次數
for(int i=0;i<chAM.length;i++)
for(int j=0;j<name.length;j++)
if(chAM[i].getSelectedItem().equals(name[j]))
AM[j]++;
//請計算每一位護士晚班次數
for(int i=0;i<chPM.length;i++)
for(int j=0;j<name.length;j++)
if(chPM[i].getSelectedItem().equals(name[j]))
PM[j]++;
//請計算每一位護士夜班次數
for(int i=0;i<chNigh.length;i++)
for(int j=0;j<name.length;j++)
if(chNigh[i].getSelectedItem().equals(name[j]))
Nigh[j]++;
//將資料填入畫面
for(int i=0; i<AM.length; i++)
{
lbAM[i].setText("" + AM[i]);
lbPM[i].setText("" + PM[i]);
lbNigh[i].setText("" + Nigh[i]);
}
}
//建立一個用來處理按鈕的 ActionListener inner class
class act implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
if(e.getSource() == b2)
{
System.exit(0);
}
else if(e.getSource() == b1)
{
StringBuffer sbAM = new StringBuffer("");
StringBuffer sbPM = new StringBuffer("");
StringBuffer sbNight = new StringBuffer("");
//請撰寫這部份，將排班資料寫入檔案
try
{
System.out.println("Writing JDA02.txt");
bw = new BufferedWriter(new FileWriter("JDA02.txt"));
bw.write("值班通知書");
bw.newLine();
bw.newLine();
for(int h=0;h<name.length;h++){
sbAM= new StringBuffer("");
sbPM=new StringBuffer("");
sbNight=new StringBuffer("");
bw.write(name[h]+".");
bw.newLine();
bw.newLine();
for(int i = 0;i<chAM.length;i++)
if(chAM[i].getSelectedItem().equals(name[h]))
sbAM.append(" ").append(weekDay[i]);
bw.write("早班"+sbAM);
bw.newLine();
for(int i = 0;i<chPM.length;i++)
if(chPM[i].getSelectedItem().equals(name[h]))
sbPM.append(" ").append(weekDay[i]);
bw.write("晚班"+sbPM);
bw.newLine();
for(int i = 0;i<chNigh.length;i++)
if(chNigh[i].getSelectedItem().equals(name[h]))
sbNight.append(" ").append(weekDay[i]);
bw.write("夜班"+sbNight);
bw.newLine();
bw.newLine();
}
bw.close();
}
catch (Exception ex) {
ex.printStackTrace();
}
}
}
}
/* 覆寫 WindowAdapter 中的 windowClosing()
讓關閉視窗的按鈕有作用
*/
class WinListener extends WindowAdapter
{
public void windowClosing(WindowEvent e)
{
e.getWindow().dispose();
System.exit(0);
}
}
}

參考答案
import java.io.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class JDD02 extends JFrame implements ActionListener
{
//第一個JPanel用來放置所選取檔案
JPanel pn1 = new JPanel();
//顯示訊息的標籤
JLabel msg = new JLabel("請選取兩個 txt 檔來做合併");
//按鈕上的圖示
ImageIcon image1=new ImageIcon("JDD02-1.gif");
ImageIcon image2=new ImageIcon("JDD02-1.gif");
ImageIcon image3=new ImageIcon("JDD02-2.gif");
//選取檔案的按鈕
JButton bn1=new JButton("選取要合併的第一個檔案",image1);
JButton bn2=new JButton("選取要合併的第二個檔案",image2);
JButton bn3=new JButton("選取合併後要存入的檔案",image3);
//顯示所選取檔案名稱
JTextField tfIn[]={new JTextField(),new JTextField()};
//顯示所要輸出的檔案名稱
JTextField tf3=new JTextField(3);
//第二個JPanel用來放置按鈕
JPanel pn2 = new JPanel();
JButton bnOK = new JButton("確定");
JButton bnExit = new JButton("離開");
//合併檔案所用的 IO 類別
JFileChooser jfc = new JFileChooser(".");
InputStream is;
SequenceInputStream sis;
File outputFile;
FileOutputStream out;
public JDD02( ) { addWindowListener(new WinListener()); }
public static void main(String[] args) throws IOException
{
JDD02 test = new JDD02();
test.setTitle("文字檔合併器");
test.setup();
test.setSize(300,200);
test.setVisible(true);
}
//設定畫面元件及 Listener
void setup()
{
Container content = this.getContentPane();
pn1.setLayout(new GridLayout(0,1));
pn1.add(msg);
bn1.addMouseListener(new MouseListen());
bn2.addMouseListener(new MouseListen());
bn3.addMouseListener(new MouseListen());
bn1.addActionListener(this);
bn2.addActionListener(this);
bn3.addActionListener(this);
pn1.add(bn1);
pn1.add(tfIn[0]);
pn1.add(bn2);
pn1.add(tfIn[1]);
pn1.add(bn3);
pn1.add(tf3);
content.add(pn1);
bnOK.addMouseListener(new MouseListen());
bnExit.addMouseListener(new MouseListen());
bnOK.addActionListener(this);
bnExit.addActionListener(this);
pn2.add(bnOK);
pn2.add(bnExit);
content.add(pn2,BorderLayout.SOUTH);
}
// 顯示開啟檔案對話方塊,並將所選取的檔案名稱放入 JTextField tfIn[] 中
void selectInFile(int i)
{
//回傳值為 0 代表使用者不是選擇 Cancel
if(jfc.showOpenDialog(this)==0){
tfIn[i-1].setText(jfc.getSelectedFile().toString());
}
}
// 顯示開啟檔案對話方塊,並將所選取的檔案名稱放入 JTextField tf3 中
void selectOutFile()
{
//回傳值為 0 代表使用者不是選擇 Cancel
if(jfc.showOpenDialog(this)==0){
tf3.setText(jfc.getSelectedFile().toString());
}
}
//進行檔案合併的動作
void combineFiles()
{
try
{
InputStream in0 = new FileInputStream(tfIn[0].getText().trim());
InputStream in1 = new FileInputStream(tfIn[1].getText().trim());
sis = new SequenceInputStream(in0,in1);
outputFile = new File(tf3.getText().trim());
out=new FileOutputStream(outputFile);
int c;
while((c=sis.read())!=-1)
{
System.out.write(c);
out.write(c);
}
sis.close();
out.close();
msg.setText("檔案合併完成");
tfIn[0].setText("");
tfIn[1].setText("");
tf3.setText("");
}
catch (Exception ex)
{
msg.setText("檔案合併失敗");
}
}
//對按鈕的動作做出回應
public void actionPerformed(ActionEvent e)
{
if(e.getSource() == bnExit)
{
//結束程式
dispose();
System.exit(0);
}
else if(e.getSource() == bnOK)
{
//進行檔案合併
combineFiles();
}
else if(e.getSource() == bn1)
{
// 顯示開啟檔案對話方塊,並將所選取的檔案名稱放入 JTextField tf[0] 中
selectInFile(1);
}
else if(e.getSource() == bn2)
{
selectInFile(2);
}
else if(e.getSource() == bn3)
{
selectOutFile();
}
}
//用來讓JFrame可以正常結束
class WinListener extends WindowAdapter
{
public void windowClosing(WindowEvent e)
{
e.getWindow().dispose();
System.exit(0);
}
}
//讓按鈕在滑鼠進入會變色
class MouseListen extends MouseAdapter
{
public void mouseEntered(MouseEvent e)
{
((JButton)(e.getSource())).setBackground(Color.YELLOW);
}
public void mouseExited(MouseEvent e)
{
((JButton)e.getSource()).setBackground(new Color(204,204,204));
}
}
}

參考答案
import java.awt.*;
import java.awt.event.*;
class JDD02 extends Frame
implements MouseListener, MouseMotionListener {
String msg="", info="";
int mouseX=0, mouseY=0 ;
public static void main(String arg[])
{
JDD02 mew=new JDD02();
}
//ctor
JDD02() {
super("滑鼠感應視窗");
addMouseListener(this);
addMouseMotionListener(this);
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent we) {
dispose();
}
});
setBackground(Color.white);
setSize(250,200);
//setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
public void mouseClicked(MouseEvent me) {
}
public void mouseEntered(MouseEvent me) {
//請在此撰寫滑鼠移入事件
this.setBackground(Color.yellow);
this.repaint();
}
public void mouseExited(MouseEvent me) {
//請在此撰寫滑鼠移出視窗事件
this.setBackground(Color.white);
mouseX=me.getX();
mouseY=me.getY();
info = "Mouse just left the window from ";
repaint();
}
public void mousePressed(MouseEvent me) {
//請在此撰寫滑鼠按下事件
mouseX=me.getX();
mouseY=me.getY();
msg="Down";
info="Mouse is pressed at ";
repaint();
}
public void mouseReleased(MouseEvent me) {
//請在此撰寫滑鼠放開事件
mouseX=me.getX();
mouseY=me.getY();
msg="Up";
info="Mouse is released from ";
repaint();
}
public void mouseDragged(MouseEvent me) {
//請在此撰寫滑鼠拖曳事件
mouseX=me.getX();
mouseY=me.getY();
msg="Dragging";
info="Mouse is Dragging at ";
repaint();
}
public void mouseMoved(MouseEvent me) {
//請在此撰寫滑鼠移動事件
mouseX=me.getX();
mouseY=me.getY();
msg="";
info="Mouse is moving to ";
repaint();
}
public void paint(Graphics g) {
//請在此撰寫撰寫程式取得滑鼠座標
g.drawString(msg, mouseX, mouseY);
g.drawString(info+mouseX+","+mouseY, 10, 40);
}
}

參考答案
import java.awt.event.*;
import javax.swing.*;
class JDD01
{
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new MyJFrame().setVisible(true);
}
});
}
}
class MyJFrame extends javax.swing.JFrame {
private ButtonGroup answers;
private JRadioButton baseball;
private JRadioButton basketball;
private JRadioButton tennis;
private JRadioButton other;
private JButton okBtn;
private JTextField otherBallGame;
private JLabel question;
private String favoriteBallGame="棒球";
public MyJFrame() {
answers = new ButtonGroup();
okBtn = new JButton();
question = new JLabel();
baseball = new JRadioButton();
basketball = new JRadioButton();
tennis = new JRadioButton();
other = new JRadioButton();
otherBallGame = new JTextField();
setSize(340,290);
setLocationRelativeTo(null);
setLayout(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
setTitle("問卷調查");
okBtn.setText("確定");
okBtn.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent evt){
String tmp;
if(favoriteBallGame.equals(""))
tmp = otherBallGame.getText();
else
tmp = favoriteBallGame;
JOptionPane.showMessageDialog(MyJFrame.this, "你最喜好的球類運動是"+tmp,"test",JOptionPane.INFORMATION_MESSAGE);
}
});
question.setText("下列何者是您最喜好的球類運動？(單選)");
answers.add(baseball);
baseball.setText("棒球");
baseball.setSelected(true);
baseball.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent evt){
otherBallGame.setEnabled(false);
favoriteBallGame="棒球";
}
});
answers.add(basketball);
basketball.setText("籃球");
basketball.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent evt)
{
otherBallGame.setEnabled(false);
favoriteBallGame="籃球";
}
});
answers.add(tennis);
tennis.setText("網球");
tennis.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent evt){
otherBallGame.setEnabled(false);
favoriteBallGame="網球";
}
});
answers.add(other);
other.setText("其它");
other.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent evt){
otherBallGame.setEnabled(true);
favoriteBallGame = "";
}
});
otherBallGame.setEnabled(false);
question.setSize(240, 30);
question.setLocation(50,20);
baseball.setSize(100,30);
baseball.setLocation(50,50);
basketball.setSize(100,30);
basketball.setLocation(50,80);
tennis.setSize(100,30);
tennis.setLocation(50,110);
other.setSize(70,30);
other.setLocation(50, 140);
otherBallGame.setSize(100,20);
otherBallGame.setLocation(120, 145);
okBtn.setSize(100,20);
okBtn.setLocation(120, 200);
getContentPane().add(question);
getContentPane().add(baseball);
getContentPane().add(basketball);
getContentPane().add(tennis);
getContentPane().add(other);
getContentPane().add(otherBallGame);
getContentPane().add(okBtn);
}
}

參考答案
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
class JDD01
{
public static void main(String[] args)
{
new MyFrame();
}
}
class MyFrame extends JFrame
{
Color curColor;
MyFrame()
{
//視窗大小、標題、位置與關閉事件設定
setSize(640,480);
setTitle("畫筆功能");
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
//加入自訂容器至中央區塊
setLayout(new BorderLayout());
add(new MyPanel(this), BorderLayout.CENTER);
setVisible(true);
}
}
class MyPanel extends Panel
{
MyFrame parent;
int curX,curY,lastX=-1,lastY=-1;
public MyPanel(MyFrame p)
{
parent = p;
setSize(600,480);
setBackground(Color.WHITE);
//當滑鼠按下時
this.addMouseListener(new MouseAdapter(){
public void mousePressed(MouseEvent e){
lastX=e.getX();
lastY=e.getY();//紀錄目前座標
}
});
//當滑鼠拖曳時
this.addMouseMotionListener(new MouseAdapter(){
public void mouseDragged(MouseEvent e){
Graphics g = MyPanel.this.getGraphics();
g.setColor(parent.curColor);
curX=e.getX();
curY=e.getY();
//從最後紀錄的座標畫至目前座標
g.drawLine(lastX, lastY, curX, curY);
//繪製完畢後，目前的座標成為下次繪製的起始座標
lastX=curX;
lastY=curY;
}
});
}
}

參考答案：
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
class JDD01
{
public static void main(String[] args)
{
new MyFrame();
}
}
class MyFrame extends JFrame
{
Color curColor;
MyFrame()
{
Panel toolbar;
Button redBtn, blueBtn;
//設定視窗標題、大小、位置、排版方式
this.setTitle("繪製圓形");
this.setSize(640,480);
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(EXIT_ON_CLOSE);
this.setLayout(new BorderLayout());
// 加入自訂容器至中央區塊
this.add(new MyPanel(this),BorderLayout.CENTER);
toolbar = new Panel();
curColor = Color.red; //預設繪製顏色為紅色
redBtn = new Button("Red");
blueBtn = new Button("Blue");
//按下RED按鈕時，設定目前顏色為紅色
redBtn.addMouseListener(new MouseAdapter(){
public void mousePressed(MouseEvent e){
MyFrame.this.curColor=Color.red;
}
});
//按下BLUE按鈕時，設定目前顏色為藍色
blueBtn.addMouseListener(new MouseAdapter(){
public void mousePressed(MouseEvent e){
MyFrame.this.curColor=Color.blue;
}
});
//配置下方的工具按鈕
toolbar.setLayout(new FlowLayout());
toolbar.add(redBtn);
toolbar.add(blueBtn);
this.add(toolbar, BorderLayout.SOUTH);
setVisible(true);
}
}
class MyPanel extends Panel
{
MyFrame parent;
public MyPanel(MyFrame p)
{
parent = p;
this.setSize(600,480);
this.setBackground(Color.WHITE);
//當滑鼠按下時，在目前位置以繪圖顏色畫一個20x20的圓形
addMouseListener(new MouseAdapter(){
public void mousePressed(MouseEvent e){
Graphics g = MyPanel.this.getGraphics();
g.setColor(parent.curColor);
g.fillOval(e.getX()-10, e.getY()-10, 20, 20);
}
});
}
}

1.題目說明：
2.設計說明：

參考答案：
import java.awt.event.*;
import javax.swing.*;
import java.awt.*;
 
class JDD01
{   
        public static void main(String args[]) {
        java.awt.EventQueue.invokeLater(new Runnable() {
            public void run() {
                new MyJFrame().setVisible(true);
            }
        });
    }
}
class MyJFrame extends javax.swing.JFrame {
 
    private JButton btn1, btn2, btn3, btn4, btn5;
    private LayoutManager layout;
    
    public MyJFrame() {
      
        this.setSize(500,400);
        this.setLocationRelativeTo(null);
        this.setLayout(new BorderLayout());
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    
        JButton btn1 = new JButton("Button 1");
        JButton btn2 = new JButton("Button 2");
        JButton btn3 = new JButton("Button 3");
        JButton btn4 = new JButton("Button 4");
        JButton btn5 = new JButton("Button 5");
        this.getContentPane().add(btn1, BorderLayout.CENTER);
        this.getContentPane().add(btn2, BorderLayout.EAST);
        this.getContentPane().add(btn3, BorderLayout.SOUTH);
        this.getContentPane().add(btn4, BorderLayout.WEST);
        this.getContentPane().add(btn5, BorderLayout.NORTH);
    }
}

參考答案：
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class JDD01
{
    public static void main(String args[])
    {
        new MyApp();
    }
}
class MyApp
{
    MyApp()
    {
        JFrame f = new JFrame();  //建立新視窗
        f.setSize(200, 200);  //設定寬高
        f.setVisible(true);  //讓視窗顯示在螢幕
        f.setLocationRelativeTo(null);  //設定視窗位置在螢幕中央
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    //設定當視窗被關閉時，執行關閉動作
        
        //建立選擇顏色視窗(在f視窗之上,標題,預設選擇的顏色是f視窗的背景色)
        Color c = JColorChooser.showDialog(f, "Choose Background Color", f.getContentPane().getBackground());
        
        f.getContentPane().setBackground(c); //改變背景色
    }
}

參考答案：
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class JDD01
{
    public static void main(String args[])
    {
        new MyApp();
    }
}
class MyApp
{
    MyApp()
    {
        JFrame f = new JFrame();
        f.setSize(300, 200);
        f.setVisible(true);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setLocationRelativeTo(null);
        
        JFileChooser chooser = new JFileChooser();
        
        String[] exts={".java",".class"};
        AppFiles filter = new AppFiles(exts,"Java-Related Files");
        chooser.setFileFilter(filter);
        int returnVal = chooser.showOpenDialog(f);
        
        if(returnVal==JFileChooser.APPROVE_OPTION)
            f.setTitle(chooser.getSelectedFile().getName());  //如果使用者有選擇檔案，改變視窗標題
        else
            f.setTitle("You don`t choose any file");  //沒有回傳值代表沒有選擇
    }
}
class AppFiles extends javax.swing.filechooser.FileFilter  //建立繼承FileFilter的class，命名為AppFiles
{
    String[] extensions;
    String description;
    
    AppFiles(String[] exts,String descr)
    {
        extensions = exts;
        description = descr;
        
        for(int i=0;i<exts.length;i++)
            extensions[i] = exts[i].toLowerCase();
    }
    @Override  //此Function為FileFilter強制實作
    public boolean accept(File f) {
        // TODO Auto-generated method stub
        if(f.isDirectory())  
            return true;
        else
        {
            String fname = f.getName().toLowerCase();  //取得完整檔名，並全數轉為小寫
            for(String s:extensions)
            {
                if(fname.endsWith(s))  //看字串的尾端是否和extentions內的字串相等 (比對副檔名)
                return true; //如果其中一個相等回傳true
            }
        }
        
        return false; //找不到就會跳出迴圈，回傳false
    }
    @Override //此Function為FileFilter強制實作
    public String getDescription() {
        // TODO Auto-generated method stub
        return description;  
    }
    
    
}