正文
java记事本源代码完整,java记事本代码讲解
提示：扫一扫查出行【扫一扫了解最新限行尾号】
复制提示
Java记事本源代码
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.Transferable;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.InputEvent;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.KeyStroke;
import javax.swing.filechooser.FileFilter;
public class Demo extends JFrame {
private static final long serialVersionUID = 1L; //Eclipse自动生成序列号
String name = "无标题";
JPanel menuPanel = new JPanel();
JTextArea text = new TextAreaMenu(); //文本编辑区
JScrollPane jsp = new JScrollPane(text); //可滚动编辑区
JMenuBar mnbMain = new JMenuBar();
JMenu mnServer = new JMenu("文件(F)");
JMenu mnEdit = new JMenu("编辑(E)");
JMenuItem[] mniServers = new JMenuItem[]{
new JMenuItem("新建(N)"),
new JMenuItem("保存(S)"),
new JMenuItem("打开(O)"),
new JMenuItem("退出(X)"),
};
{
menuPanel.setLayout(new FlowLayout(FlowLayout.LEFT, 0, 0));
mnbMain.add(mnServer);
menuPanel.add(mnbMain);
mnbMain.setBounds(5, 0, 50, 30);
for (int i = 0; i mniServers.length; i++) {
mnServer.add(mniServers[i]);
}
mniServers[0].addActionListener(new ActionListener() { //定义"新建"组件操作
@Override
public void actionPerformed(ActionEvent arg0) {
new Demo(getLocation().x+15,getLocation().y+5);
}
});
mniServers[1].addActionListener(new ActionListener() { //定义"保存"组件操作
@Override
public void actionPerformed(ActionEvent arg0) {
chooseToSave();
}
});
mniServers[2].addActionListener(new ActionListener() { //定义"打开"组件操作
@Override
public void actionPerformed(ActionEvent arg0) {
chooseToOpen();
}
});
mniServers[3].addActionListener(new ActionListener() { //定义"退出"组件操作
@Override
public void actionPerformed(ActionEvent arg0) {
System.exit(0);
}
});
text.addFocusListener(new FocusListener() {
@Override
public void focusLost(FocusEvent e) {
// TODO Auto-generated method stub
}
@Override
public void focusGained(FocusEvent e) {
}
});
}
public Demo(int x,int y) {
this.setTitle( name +" - 记事本");
this.setBounds(x, y, 600, 400);
this.setLayout(new BorderLayout());
this.add(menuPanel, BorderLayout.NORTH);
this.add(jsp);
jsp.setBounds(5, 30, getWidth()-10, getHeight()-50);
this.setDefaultCloseOperation(DISPOSE_ON_CLOSE);
this.setVisible(true);
}
public Demo() {
this(200,200);
}
protected void chooseToSave() {
File file = chooseFile();
if(null==file)return;
if(file.exists()){
int cho = JOptionPane.showConfirmDialog(this, "文件已存在，是否覆盖？");
System.out.println(cho);
if(cho==JOptionPane.OK_OPTION)save(file);
else return;
}
else save(file);
}
private void save(File file) {
name = file.getName();
write(text.getText(),file.getPath());
this.setTitle( name +" - 记事本");
}
protected void chooseToOpen() {
File file = chooseFile();
if(null==file||!file.exists())return;
name = file.getName();
Demo.this.setTitle( name +" - 记事本");
read(text,file);
}
/*********************************************MAIN**************************************************/
public static void main(String[] args) {
new Demo();
}
private File chooseFile(){
JFileChooser chooser = new JFileChooser(); //构建文件选择器
chooser.setFileFilter(new FileFilter() {
@Override
public String getDescription() {
return "文本文件";
}
@Override
public boolean accept(File f) {
String name = f.getName().toLowerCase();
return f.isDirectory() || name.endsWith(".txt")
||name.endsWith(".c") || name.endsWith(".java")
||name.endsWith(".cpp"); //可识别文件
}
});
int result = chooser.showDialog(null, "确定");
if (result==JFileChooser.APPROVE_OPTION) {
File file = chooser.getSelectedFile();
System.out.println(file.getAbsolutePath());
} else {
System.out.println("未选择文件");
}
return chooser.getSelectedFile();
}
public static void read(JTextArea text,File file){ //定义读取文件操作
FileReader fr;
try {
fr = new FileReader(file);
BufferedReader br = new BufferedReader(fr);
String string = null;
while((string = br.readLine()) != null){
text.append(string+"\n");
}
br.close();
fr.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public static void write(String txt,String fileName){
FileWriter fw;
try {
fw = new FileWriter(fileName);
BufferedWriter bw = new BufferedWriter(fw);
bw.write(txt);
bw.flush();
bw.close();
fw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
class TextAreaMenu extends JTextArea implements MouseListener {
private static final long serialVersionUID = -2308615404205560110L;
private JPopupMenu pop = null; // 弹出菜单
private JMenuItem selectAll = null,copy = null, paste = null, cut = null, cancel=null; // 功能菜单
public TextAreaMenu() {
super();
init();
}
private void init() {
this.addMouseListener(this);
this.setSelectedTextColor(Color.red);
pop = new JPopupMenu();
pop.add(selectAll = new JMenuItem("全选"));
pop.add(copy = new JMenuItem("复制"));
pop.add(paste = new JMenuItem("粘贴"));
pop.add(cut = new JMenuItem("剪切"));
pop.add(cancel = new JMenuItem("撤销"));
selectAll.setAccelerator(KeyStroke.getKeyStroke('A', InputEvent.CTRL_MASK));
copy.setAccelerator(KeyStroke.getKeyStroke('C', InputEvent.CTRL_MASK));
paste.setAccelerator(KeyStroke.getKeyStroke('V', InputEvent.CTRL_MASK));
cut.setAccelerator(KeyStroke.getKeyStroke('X', InputEvent.CTRL_MASK));
cancel.setAccelerator(KeyStroke.getKeyStroke('Z', InputEvent.CTRL_MASK));
copy.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
action(e);
}
});
paste.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
action(e);
}
});
cut.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
action(e);
}
});
this.add(pop);
}
/**
* 菜单动作
* @param e
*/
public void action(ActionEvent e) {
String str = e.getActionCommand();
if (str.equals(selectAll.getText())) { // 全选
this.selectAll();
}
else if (str.equals(copy.getText())) { // 复制
this.copy();
} else if (str.equals(paste.getText())) { // 粘贴
this.paste();
} else if (str.equals(cut.getText())) { // 剪切
this.cut();
}
else if (str.equals(cancel.getText())) { //撤销
this.cut();
}
}
public JPopupMenu getPop() {
return pop;
}
public void setPop(JPopupMenu pop) {
this.pop = pop;
}
/**
* 剪切板中是否有文本数据可供粘贴
*
* @return true为有文本数据
*/
public boolean isClipboardString() {
boolean b = false;
Clipboard clipboard = this.getToolkit().getSystemClipboard();
Transferable content = clipboard.getContents(this);
try {
if (content.getTransferData(DataFlavor.stringFlavor) instanceof String) {
b = true;
}
} catch (Exception e) {
}
return b;
}
/**
* 文本组件中是否具备复制的条件
*
* @return true为具备
*/
public boolean isCanCopy() {
boolean b = false;
int start = this.getSelectionStart();
int end = this.getSelectionEnd();
if (start != end)
b = true;
return b;
}
public void mouseClicked(MouseEvent e) {
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
if (e.getButton() == MouseEvent.BUTTON3) {
copy.setEnabled(isCanCopy());
paste.setEnabled(isClipboardString());
cut.setEnabled(isCanCopy());
pop.show(this, e.getX(), e.getY());
}
}
public void mouseReleased(MouseEvent e) {
}
}
相关问答
Q1: java记事本源代码
给你个做好了的Java的源程序的记事本，自己看看就行了的，不怎么难的···
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import javax.swing.*;
public class MyNotepad implements ActionListener{
private JFrame frame=new JFrame("新记事本");
private JTextArea jta=new JTextArea();
private String result="";
private boolean flag=true;
private File f;
private JButton jb=new JButton("开始");
private JTextField jtf=new JTextField(15);
private JTextField jt=new JTextField(15);
private JButton jbt=new JButton("替换为");
private JButton jba=new JButton("全部替换");
private Icon ic=new ImageIcon("D:\\java课堂笔记\\GUI\\11.gif");
private String value;
private int start=0;
private JFrame jf=new JFrame("查找");
private JFrame jfc=new JFrame("替换");
@Override
public void actionPerformed(ActionEvent e) {
String comm=e.getActionCommand();
if("新建".equals(comm)){
if(!(frame.getTitle().equals("新记事本"))){
if(!flag){
write();
newNew();
}else{
JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");
int returnVal = jfc.showDialog(null,"保存为");
if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性
f=jfc.getSelectedFile();
flag=false;
write();
}
}
}else if(!(jta.getText().isEmpty())){
JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");
int returnVal = jfc.showDialog(null,"保存为");
if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性
f=jfc.getSelectedFile();
flag=false;
write();
newNew();
}
}else{
newNew();
}
}else if("打开".equals(comm)){
JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");
jfc.setDialogType(JFileChooser.OPEN_DIALOG);
int returnVal = jfc.showOpenDialog(null);
if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性
f=jfc.getSelectedFile();
frame.setTitle(f.getName());
result=read();
flag=false;
value=result;
jta.setText(result);
}
}else if("保存".equals(comm)){
JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");
if(flag){
int returnVal = jfc.showDialog(null,"保存为");
if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性
f=jfc.getSelectedFile();
flag=false;
write();
}
}else{
write();
}
}else if("另存".equals(comm)){
JFileChooser jfc=new JFileChooser("D:\\java课堂笔记");
int returnVal = jfc.showDialog(null,"另存");
if(returnVal == JFileChooser.APPROVE_OPTION) {//选择文件后再执行下面的语句，保证了程序的健壮性
f=jfc.getSelectedFile();
write();
}
}else if("退出".equals(comm)){
System.exit(0);
}else if("撤销".equals(comm)){
jta.setText(value);
}else if("剪切".equals(comm)){
value=jta.getText();
jta.cut();
}else if("复制".equals(comm)){
jta.copy();
}else if("粘贴".equals(comm)){
value=jta.getText();
jta.paste();
}else if("删除".equals(comm)){
value=jta.getText();
jta.replaceSelection(null);
}else if("全选".equals(comm)){
jta.selectAll();
}else if("查找".equals(comm)){
value=jta.getText();
jf.add(jtf,BorderLayout.CENTER);
jf.add(jb,BorderLayout.SOUTH);
jf.setLocation(300,300);
jf.pack();
jf.setVisible(true);
jf.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}else if("替换".equals(comm)){
value=jta.getText();
GridLayout gl=new GridLayout(3,3);
JLabel jl1=new JLabel("查找内容:");
JLabel jl2=new JLabel("替换为:");
jfc.setLayout(gl);
jfc.add(jl1);
jfc.add(jtf);
jfc.add(jb);
jfc.add(jl2);
jfc.add(jt);
jfc.add(jbt);
JLabel jl3=new JLabel();
JLabel jl4=new JLabel();
jfc.add(jl3);
jfc.add(jl4);
jfc.add(jba);
jfc.setLocation(300,300);
jfc.pack();
jfc.setVisible(true);
jfc.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}else if("版本".equals(comm)){
JDialog jd=new JDialog(frame,"关于对话框");
jd.setSize(200,200);
JLabel l=new JLabel("哈哈哈哈哈哈哈哈哈哈呵呵呵呵呵呵呵呵呵呵呵呵呵");
jd.add(l,BorderLayout.CENTER);
jd.setLocation(100,200);
jd.setSize(300,300);
jd.setVisible(true);
// jd.pack();
jd.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
}else if("开始".equals(comm)||"下一个".equals(comm)){
String temp=jtf.getText();
int s=value.indexOf(temp,start);
if(value.indexOf(temp,start)!=-1){
jta.setSelectionStart(s);
jta.setSelectionEnd(s+temp.length());
jta.setSelectedTextColor(Color.GREEN);
start=s+1;
jb.setText("下一个");
// value=value.substring(s+temp.length());//不能截取字串
}else {
JOptionPane.showMessageDialog(jf, "查找完毕!", "提示", 0, ic);
jf.dispose();
}
}else if("替换为".equals(comm)){
String temp=jtf.getText();
int s=value.indexOf(temp,start);
if(value.indexOf(temp,start)!=-1){
jta.setSelectionStart(s);
jta.setSelectionEnd(s+temp.length());
jta.setSelectedTextColor(Color.GREEN);
start=s+1;
jta.replaceSelection(jt.getText());
}else {
JOptionPane.showMessageDialog(jf, "查找完毕!", "提示", 0, ic);
jf.dispose();
}
}else if("全部替换".equals(comm)){
String temp=jta.getText();
temp=temp.replaceAll(jtf.getText(), jt.getText());
jta.setText(temp);
}
}
public String read(){
String temp="";
try {
FileInputStream fis = new FileInputStream(f.getAbsolutePath());
byte[] b=new byte[1024];
while(true){
int num=fis.read(b);
if(num==-1)break;
temp=temp+new String(b,0,num);
}
fis.close();
} catch (Exception e1) {
e1.printStackTrace();
}
return temp;
}
public void write(){
try {
FileOutputStream fos=new FileOutputStream(f);
fos.write(jta.getText().getBytes());
fos.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public void newNew(){
frame.dispose();
new MyNotepad();
flag=true;
}
public MyNotepad(){
JMenuBar jmb=new JMenuBar();
String[] menuLab={"文件","编辑","帮助"};
String[][] menuItemLab={{"新建","打开","保存","另存","退出"},
{"撤销","剪切","复制","粘贴","删除","全选","查找","替换"},
{"版本"}};
for(int i=0;imenuLab.length;i++){
JMenu menu=new JMenu(menuLab[i]);
jmb.add(menu);
for(int j=0;jmenuItemLab[i].length;j++){
JMenuItem jmi=new JMenuItem(menuItemLab[i][j]);
menu.add(jmi);
jmi.addActionListener(this);
}
}
frame.setJMenuBar(jmb);
jta.setLineWrap(true);//自动换行
JScrollPane jsp=new JScrollPane(jta);//滚动窗口面板
frame.add(jsp);
jb.addActionListener(this);
jbt.addActionListener(this);
jba.addActionListener(this);
frame.setLocation(200,50);
frame.setSize(620,660);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public static void main(String[] args) {
new MyNotepad();
}
}
Q2: 用Java编写简易记事本源代码
importjava.awt.BorderLayout;importjava.awt.Container;importjava.awt.Font;importjava.awt.event.ActionEvent;importjava.awt.event.ActionListener;importjava.awt.event.InputEvent;importjava.awt.event.KeyAdapter;importjava.awt.event.KeyEvent;importjava.awt.event.MouseAdapter;importjava.awt.event.MouseEvent;importjava.awt.event.WindowAdapter;importjava.awt.event.WindowEvent;importjava.io.BufferedReader;importjava.io.BufferedWriter;importjava.io.File;importjava.io.FileReader;importjava.io.FileWriter;importjava.io.IOException;importjavax.swing.BorderFactory;importjavax.swing.JFileChooser;importjavax.swing.JFrame;importjavax.swing.JLabel;importjavax.swing.JMenu;importjavax.swing.JMenuBar;importjavax.swing.JMenuItem;importjavax.swing.JOptionPane;importjavax.swing.JPopupMenu;importjavax.swing.JScrollPane;importjavax.swing.JTextArea;importjavax.swing.KeyStroke;importjavax.swing.ScrollPaneConstants;importjavax.swing.SwingConstants;publicclassJNotePadUIextendsJFrame{privateJMenuItemmenuOpen;privateJMenuItemmenuSave;privateJMenuItemmenuSaveAs;privateJMenuItemmenuClose;privateJMenueditMenu;privateJMenuItemmenuCut;privateJMenuItemmenuCopy;privateJMenuItemmenuPaste;privateJMenuItemmenuAbout;privateJTextAreatextArea;privateJLabelstateBar;privateJFileChooserfileChooser;privateJPopupMenupopUpMenu;publicJNotePadUI(){super("新建文本文件");setUpUIComponent();setUpEventListener();setVisible(true);}privatevoidsetUpUIComponent(){setSize(640,480);//菜单栏JMenuBarmenuBar=newJMenuBar();//设置「文件」菜单JMenufileMenu=newJMenu("文件");menuOpen=newJMenuItem("打开");//快捷键设置menuOpen.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_O,InputEvent.CTRL_MASK));menuSave=newJMenuItem("保存");menuSave.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_S,InputEvent.CTRL_MASK));menuSaveAs=newJMenuItem("另存为");menuClose=newJMenuItem("关闭");menuClose.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_Q,InputEvent.CTRL_MASK));fileMenu.add(menuOpen);fileMenu.addSeparator();//分隔线fileMenu.add(menuSave);fileMenu.add(menuSaveAs);fileMenu.addSeparator();//分隔线fileMenu.add(menuClose);//设置「编辑」菜单JMenueditMenu=newJMenu("编辑");menuCut=newJMenuItem("剪切");menuCut.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_X,InputEvent.CTRL_MASK));menuCopy=newJMenuItem("复制");menuCopy.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C,InputEvent.CTRL_MASK));menuPaste=newJMenuItem("粘贴");menuPaste.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_V,InputEvent.CTRL_MASK));editMenu.add(menuCut);editMenu.add(menuCopy);editMenu.add(menuPaste);//设置「关于」菜单JMenuaboutMenu=newJMenu("关于");menuAbout=newJMenuItem("关于JNotePad");aboutMenu.add(menuAbout);menuBar.add(fileMenu);menuBar.add(editMenu);menuBar.add(aboutMenu);setJMenuBar(menuBar);//文字编辑区域textArea=newJTextArea();textArea.setFont(newFont("宋体",Font.PLAIN,16));textArea.setLineWrap(true);JScrollPanepanel=newJScrollPane(textArea,ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);ContainercontentPane=getContentPane();contentPane.add(panel,BorderLayout.CENTER);//状态栏stateBar=newJLabel("未修改");stateBar.setHorizontalAlignment(SwingConstants.LEFT);stateBar.setBorder(BorderFactory.createEtchedBorder());contentPane.add(stateBar,BorderLayout.SOUTH);popUpMenu=editMenu.getPopupMenu();fileChooser=newJFileChooser();}privatevoidsetUpEventListener(){//按下窗口关闭钮事件处理addWindowListener(newWindowAdapter(){publicvoidwindowClosing(WindowEvente){closeFile();}});//菜单-打开menuOpen.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){openFile();}});//菜单-保存menuSave.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){saveFile();}});//菜单-另存为menuSaveAs.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){saveFileAs();}});//菜单-关闭文件menuClose.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){closeFile();}});//菜单-剪切menuCut.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){cut();}});//菜单-复制menuCopy.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){copy();}});//菜单-粘贴menuPaste.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){paste();}});//菜单-关于menuAbout.addActionListener(newActionListener(){publicvoidactionPerformed(ActionEvente){//显示对话框JOptionPane.showOptionDialog(null,"程序名称:\nJNotePad\n"+"程序设计:\n\n"+"简介:\n一个简单的文字编辑器\n"+"可作为验收Java的实现对象\n"+"欢迎网友下载研究交流\n\n"+"/","关于JNotePad",JOptionPane.DEFAULT_OPTION,JOptionPane.INFORMATION_MESSAGE,null,null,null);}});//编辑区键盘事件textArea.addKeyListener(newKeyAdapter(){publicvoidkeyTyped(KeyEvente){processTextArea();}});//编辑区鼠标事件textArea.addMouseListener(newMouseAdapter(){publicvoidmouseReleased(MouseEvente){if(e.getButton()==MouseEvent.BUTTON3)popUpMenu.show(editMenu,e.getX(),e.getY());}publicvoidmouseClicked(MouseEvente){if(e.getButton()==MouseEvent.BUTTON1)popUpMenu.setVisible(false);}});}privatevoidopenFile(){if(isCurrentFileSaved()){//文件是否为保存状态open();//打开}else{//显示对话框intoption=JOptionPane.showConfirmDialog(null,"文件已修改，是否保存？","保存文件？",JOptionPane.YES_NO_OPTION,JOptionPane.WARNING_MESSAGE,null);switch(option){//确认文件保存caseJOptionPane.YES_OPTION:saveFile();//保存文件break;//放弃文件保存caseJOptionPane.NO_OPTION:open();break;}}}privatebooleanisCurrentFileSaved(){if(stateBar.getText().equals("未修改")){returnfalse;}else{returntrue;}}privatevoidopen(){//fileChooser是JFileChooser的实例//显示文件选取的对话框intoption=fileChooser.showDialog(null,null);//使用者按下确认键if(option==JFileChooser.APPROVE_OPTION){try{//开启选取的文件BufferedReaderbuf=newBufferedReader(newFileReader(fileChooser.getSelectedFile()));//设定文件标题setTitle(fileChooser.getSelectedFile().toString());//清除前一次文件textArea.setText("");//设定状态栏stateBar.setText("未修改");//取得系统相依的换行字符StringlineSeparator=System.getProperty("line.separator");//读取文件并附加至文字编辑区Stringtext;while((text=buf.readLine())!=null){textArea.append(text);textArea.append(lineSeparator);}buf.close();}catch(IOExceptione){JOptionPane.showMessageDialog(null,e.toString(),"开启文件失败",JOptionPane.ERROR_MESSAGE);}}}privatevoidsaveFile(){//从标题栏取得文件名称Filefile=newFile(getTitle());//若指定的文件不存在if(!file.exists()){//执行另存为saveFileAs();}else{try{//开启指定的文件BufferedWriterbuf=newBufferedWriter(newFileWriter(file));//将文字编辑区的文字写入文件buf.write(textArea.getText());buf.close();//设定状态栏为未修改stateBar.setText("未修改");}catch(IOExceptione){JOptionPane.showMessageDialog(null,e.toString(),"写入文件失败",JOptionPane.ERROR_MESSAGE);}}}privatevoidsaveFileAs(){//显示文件对话框intoption=fileChooser.showSaveDialog(null);//如果确认选取文件if(option==JFileChooser.APPROVE_OPTION){//取得选择的文件Filefile=fileChooser.getSelectedFile();//在标题栏上设定文件名称setTitle(file.toString());try{//建立文件file.createNewFile();//进行文件保存saveFile();}catch(IOExceptione){JOptionPane.showMessageDialog(null,e.toString(),"无法建立新文件",JOptionPane.ERROR_MESSAGE);}}}privatevoidcloseFile(){//是否已保存文件if(isCurrentFileSaved()){//释放窗口资源，而后关闭程序dispose();}else{intoption=JOptionPane.showConfirmDialog(null,"文件已修改，是否保存？","保存文件？",JOptionPane.YES_NO_OPTION,JOptionPane.WARNING_MESSAGE,null);switch(option){caseJOptionPane.YES_OPTION:saveFile();break;caseJOptionPane.NO_OPTION:dispose();}}}privatevoidcut(){textArea.cut();stateBar.setText("已修改");popUpMenu.setVisible(false);}privatevoidcopy(){textArea.copy();popUpMenu.setVisible(false);}privatevoidpaste(){textArea.paste();stateBar.setText("已修改");popUpMenu.setVisible(false);}privatevoidprocessTextArea(){stateBar.setText("已修改");}publicstaticvoidmain(String[]args){newJNotePadUI();}}
Q3: JAVA记事本的源代码
我给你如下：/*
* WriteBoard.java
*
* Created on 2006年12月19日, 下午7:26
*/
/**
*
* @author LecH.giF
*/
import java.awt.datatransfer.*;
import java.awt.event.*;
import java.awt.*;
import java.io.*;
import java.awt.FileDialog;
public class WriteBoard extends java.awt.Frame {
Clipboard clipboard =null;
FileDialog fc = new FileDialog(this);
/** Creates new form WriteBoard */
public WriteBoard() {
clipboard = getToolkit().getSystemClipboard();
initComponents();
}
/** This method is called from within the constructor to
* initialize the form.
* WARNING: Do NOT modify this code. The content of this method is
* always regenerated by the Form Editor.
*/
// editor-fold defaultstate="collapsed" desc=" Generated Code "
private void initComponents() {
textArea1 = new java.awt.TextArea();
menuBar1 = new java.awt.MenuBar();
menu1 = new java.awt.Menu();
menuItem1 = new java.awt.MenuItem();
menuItem2 = new java.awt.MenuItem();
menuItem3 = new java.awt.MenuItem();
menuItem4 = new java.awt.MenuItem();
menuItem5 = new java.awt.MenuItem();
menu2 = new java.awt.Menu();
menuItem6 = new java.awt.MenuItem();
menuItem7 = new java.awt.MenuItem();
menuItem8 = new java.awt.MenuItem();
setTitle("WriteBoard");
addWindowListener(new java.awt.event.WindowAdapter() {
public void windowClosing(java.awt.event.WindowEvent evt) {
exitForm(evt);
}
});
add(textArea1, java.awt.BorderLayout.CENTER);
menu1.setLabel("Menu");
menuItem1.setLabel("\u65b0\u5efa");
menuItem1.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
newText(evt);
}
});
menu1.add(menuItem1);
menuItem2.setLabel("\u6253\u5f00");
menuItem2.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
open(evt);
}
});
menu1.add(menuItem2);
menuItem3.setLabel("\u4fdd\u5b58");
menuItem3.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
menuItem3ActionPerformed(evt);
}
});
menu1.add(menuItem3);
menuItem4.setLabel("\u53e6\u5b58\u4e3a");
menuItem4.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
menuItem4ActionPerformed(evt);
}
});
menu1.add(menuItem4);
menuItem5.setLabel("\u9000\u51fa");
menuItem5.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
exit(evt);
}
});
menu1.add(menuItem5);
menuBar1.add(menu1);
menu2.setLabel("\u7f16\u8f91");
menuItem6.setLabel("\u526a\u5207");
menuItem6.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
menuItem6ActionPerformed(evt);
}
});
menu2.add(menuItem6);
menuItem7.setLabel("\u590d\u5236");
menuItem7.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
menuItem7ActionPerformed(evt);
}
});
menu2.add(menuItem7);
menuItem8.setLabel("\u7c98\u8d34");
menuItem8.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed(java.awt.event.ActionEvent evt) {
menuItem8ActionPerformed(evt);
}
});
menu2.add(menuItem8);
menuBar1.add(menu2);
setMenuBar(menuBar1);
pack();
}// /editor-fold
private void menuItem4ActionPerformed(java.awt.event.ActionEvent evt) {
fc.show();
if(fc.getFile()!=null){
File file = new File(fc.getFile());
try {
PrintWriter pw = new PrintWriter(file);
pw.print(textArea1.getText());
pw.flush();
pw.close();
} catch (FileNotFoundException ex) {
ex.printStackTrace();
}
}
else{
return;
}
}
private void menuItem3ActionPerformed(java.awt.event.ActionEvent evt) {
fc.show();
if(fc.getFile()!=null){
File file = new File(fc.getFile());
try {
PrintWriter pw = new PrintWriter(file);
pw.print(textArea1.getText());
pw.flush();
pw.close();
} catch (FileNotFoundException ex) {
ex.printStackTrace();
}
}
else{
return;
}
}
private void menuItem8ActionPerformed(java.awt.event.ActionEvent evt) {
Transferable contents = clipboard.getContents(this);
DataFlavor flavor = DataFlavor.stringFlavor;
if(contents.isDataFlavorSupported(flavor))
try{
String str;
str=(String)contents.getTransferData(flavor);
textArea1.append(str);
}catch(Exception e){}
}
private void menuItem7ActionPerformed(java.awt.event.ActionEvent evt) {
String temp = this.textArea1.getSelectedText();
StringSelection text = new StringSelection(temp);
clipboard.setContents(text,null);
}
private void menuItem6ActionPerformed(java.awt.event.ActionEvent evt) {
String temp = this.textArea1.getSelectedText();
StringSelection text = new StringSelection(temp);
clipboard.setContents(text,null);
int start = textArea1.getSelectionStart();
int end = textArea1.getSelectionEnd();
textArea1.replaceRange("",start,end);
}
private void open(java.awt.event.ActionEvent evt) {
fc.show();
if(fc.getFile()!=null){
File file = new File(fc.getFile());
try {
FileReader fr = new FileReader(file);
BufferedReader br = new BufferedReader(fr);
String s;
try {
while((s= br.readLine())!=null){
textArea1.append(s+"\n");
}
fr.close();
br.close();
} catch (IOException ex) {
ex.printStackTrace();
}
} catch (FileNotFoundException ex) {
ex.printStackTrace();
}
}
else{
return;
}
}
private void newText(java.awt.event.ActionEvent evt) {
this.textArea1.setText("");
}
private void exit(java.awt.event.ActionEvent evt) {
System.exit(0);
}
/** Exit the Application */
private void exitForm(java.awt.event.WindowEvent evt) {
System.exit(0);
}
/**
* @param args the command line arguments
*/
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new WriteBoard().setVisible(true);
}
});
}
// Variables declaration - do not modify
private java.awt.Menu menu1;
private java.awt.Menu menu2;
private java.awt.MenuBar menuBar1;
private java.awt.MenuItem menuItem1;
private java.awt.MenuItem menuItem2;
private java.awt.MenuItem menuItem3;
private java.awt.MenuItem menuItem4;
private java.awt.MenuItem menuItem5;
private java.awt.MenuItem menuItem6;
private java.awt.MenuItem menuItem7;
private java.awt.MenuItem menuItem8;
private java.awt.TextArea textArea1;
// End of variables declaration
}
