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import java.awt.event.ActionListener;
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import java.util.EventListener;
import java.awt.event.*;
import java.awt.*;
import java.io.*;
import java.lang.*;
import java.awt.datatransfer.*;
import javax.swing.*;
public class MiniEdit extends JFrame implements ActionListener {
/**
* Method main
*
*
* @param args
*
*/
MenuBar menuBar = new MenuBar();
Menu file = new Menu("File"),
edit = new Menu("Edit"),
help = new Menu("Help");
MenuItem[] menuItem ={
new MenuItem("New"),
new MenuItem("Open"),
new MenuItem("Save"),
new MenuItem("Exit"),
new MenuItem("Select All"),
new MenuItem("Copy"),
new MenuItem("Cut"),
new MenuItem("Paste"),
new MenuItem("Help")
};
TextArea textArea = new TextArea();
String fileName = "NoName";
Toolkit toolKit = Toolkit.getDefaultToolkit();
Clipboard clipboard = toolKit.getSystemClipboard();
//opne and close message dialogs
private FileDialog openFileDialog =
new FileDialog(this,"Open File",FileDialog.LOAD);
private FileDialog saveFileDialog =
new FileDialog(this,"Save File",FileDialog.SAVE);
public static void main(String[] args) {
// TODO: Add your code here
MiniEdit MyEdit = new MiniEdit();
MyEdit.show();
}
/**
* Method MiniEdit
*
*
*/
public MiniEdit() {
// TODO: Add your code here
setTitle("MiniEdit");
setFont(new Font("Times New Roman",Font.PLAIN,15));
setBackground(Color.white);
setSize(500,500);
setMenuBar(menuBar);
menuBar.add(file);
menuBar.add(edit);
menuBar.add(help);
for(int i=0;i4;i++)
{
file.add(menuItem[i]);
edit.add(menuItem[i+4]);
}
help.add(menuItem[8]);
add(textArea);
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
e.getWindow().dispose();
System.exit(0);
}
});
//add actionListener
for(int i=0;imenuItem.length;i++)
{
menuItem[i].addActionListener(this);
}
}
/**
* Method actionPerformed
*
*
* @param e
*
*/
public void actionPerformed(ActionEvent e) {
// TODO: Add your code here
Object eventSource = e.getSource();
if(eventSource == menuItem[0])//newItem
{
textArea.setText("");
}
else if(eventSource == menuItem[1])//OpenItem
{
openFileDialog.show();
fileName = openFileDialog.getDirectory()+openFileDialog.getFile();
if(fileName != null)
{
openFile(fileName);
}
}
else if(eventSource ==menuItem[2])//SaveItem
{
saveFileDialog.show();
fileName = saveFileDialog.getDirectory()+saveFileDialog.getFile();
if(fileName !=null)
{
writeFile(fileName);
}
}
else if(eventSource==menuItem[3])//exitItem
{
System.exit(0);
}
else if(eventSource == menuItem[4])//Select All
{
textArea.selectAll();
}
else if(eventSource == menuItem[5])//copy
{
String text = textArea.getSelectedText();
StringSelection selection= new StringSelection(text);
clipboard.setContents(selection,null);
}
else if(eventSource == menuItem[6])//cut
{
String text = textArea.getSelectedText();
StringSelection selection = new StringSelection(text);
clipboard.setContents(selection,null);
textArea.replaceText("",textArea.getSelectionStart(),
textArea.getSelectionEnd());
}
else if(eventSource == menuItem[7])//Paste
{
Transferable contents = clipboard.getContents(this);
if(contents==null)
return;
String text;
text="";
try{
text = (String)contents.getTransferData(DataFlavor.stringFlavor);
}catch(Exception ex){}
textArea.replaceText(text,
textArea.getSelectionStart(),textArea.getSelectionEnd());
}
else if(eventSource == menuItem[8])
{
// JOptionPane.showMessageDialog(null,"This is a MiniEdit.");
}
}
//Read file
public void openFile(String fileName){
try{
File file = new File(fileName);
FileReader readIn = new FileReader(file);
int size = (int)file.length();
int charsRead = 0;
char[] content = new char[size];
while(readIn.ready())
charsRead += readIn.read(content,charsRead,size-charsRead);
readIn.close();
textArea.setText(new String(content,0,charsRead));
}catch(Exception e)
{
System.out.println("Error opening file!");
}
}
//write file
public void writeFile(String fileName){
try{
File file = new File(fileName);
FileWriter write = new FileWriter(file);
write.write(textArea.getText());
write.close();
}catch(Exception e){
System.out.println("Error closing file!");
就这样交，不会错的
//继承的类换一下，应该用swing包里面
class Jsben extends Frame { -- class Jsben extends JFrame {
frame的方法setMenuBar(bar);和setJMenuBar(bar);这个不太一样，功能类似
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();
}
}
import java.awt.BorderLayout;
import java.awt.FileDialog;
import java.awt.Font;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.DataFlavor;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.datatransfer.UnsupportedFlavorException;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
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.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.border.TitledBorder;
/*因为根据个人的电脑路径可能有所偏差，没有源路径的情况下，设置默认保存路径为D盘根目录下
* 若要选择保存其他地方，可以选择 另存为*/
public class TestDemo extends JFrame {
private static final long serialVersionUID = -5355432125621015300L;
private String url = null;//文件路径
private String str=null;//复制或剪切 的字符串
private StringSelection stringSelection=null;
private Clipboard clipboard=new Clipboard(str);
private Transferable transferable=null;
private DataFlavor flavor=null;
public TestDemo() {
init();
}
private void init() {
setTitle("我的记事本");
setSize(500, 600);
setContentPane(createContentPane());//添加主面板
}
/*创建主面板*/
private JPanel createContentPane() {
JPanel pane = new JPanel(new BorderLayout());
pane.add(BorderLayout.NORTH, createChocePane());//添加菜单栏
pane.add(createAreaPane());//添加文本编辑区域
return pane;
}
/*创建菜单栏，以及实现功能*/
private JPanel createChocePane() {
JPanel pane = new JPanel();
JMenuBar menuBar1 = new JMenuBar();
JMenu menu = new JMenu("文件");
menuBar1.add(menu);
JMenuItem menuIt1 = new JMenuItem("新建");
JMenuItem menuIt2 = new JMenuItem("打开");
JMenuItem menuIt3 = new JMenuItem("保存");
JMenuItem menuIt4 = new JMenuItem("另存为");
menu.add(menuIt1);
menu.add(menuIt2);
menu.add(menuIt3);
menu.add(menuIt4);
JMenuBar menuBar2 = new JMenuBar();
JMenu menu2 = new JMenu("编辑");
menuBar2.add(menu2);
JMenuItem menuIt5 = new JMenuItem("复制");
JMenuItem menuIt6 = new JMenuItem("剪切");
JMenuItem menuIt7 = new JMenuItem("粘帖");
menu2.add(menuIt5);
menu2.add(menuIt6);
menu2.add(menuIt7);
JMenuBar menuBar3 = new JMenuBar();
JMenu menu3 = new JMenu("帮助");
menuBar3.add(menu3);
JMenuItem menuIt8 = new JMenuItem("关于记事本");
menu3.add(menuIt8);
pane.add(menuBar1);
pane.add(menuBar2);
pane.add(menuBar3);
menuIt1.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
testArea.setText(null);
}
});
menuIt2.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
final FileDialog fd = new FileDialog(new JFrame(), "查找文件",
FileDialog.LOAD);
fd.setVisible(true);
if (fd.getDirectory() != null fd.getFile() != null) {
testArea.setText(null);
url = fd.getDirectory() + fd.getFile();
try {
BufferedReader in = new BufferedReader(new FileReader(
url));
for (int i = 0;; i++) {
testArea.append(in.readLine());
if (in.read() == -1) {
break;
} else
continue;
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
}
});
menuIt3.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (url==null) {
url="D:\\新建 文本文档.txt";
}
File f = new File(url);
BufferedWriter out = null;
try {
out = new BufferedWriter(new FileWriter(url));
f.createNewFile();
out.append(testArea.getText());
out.flush();
} catch (IOException e1) {
e1.printStackTrace();
} finally {
try {
out.close();
} catch (IOException e1) {
e1.printStackTrace();
}
}
}
});
menuIt4.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
FileDialog fd = new FileDialog(new JFrame(), "保存文本",
FileDialog.SAVE);
fd.setVisible(true);
if (url!=null) {
File f = new File(url);
BufferedWriter out = null;
try {
f.createNewFile();
out = new BufferedWriter(new FileWriter(url));
out.append(testArea.getText());
out.flush();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
});
menuIt5.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
str=testArea.getSelectedText();
stringSelection=new StringSelection(str);
clipboard.setContents(stringSelection, null);
}
});
menuIt6.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
str=testArea.getSelectedText();
stringSelection=new StringSelection(str);
clipboard.setContents(stringSelection, null);
int start=testArea.getSelectionStart();
int end=testArea.getSelectionEnd();
testArea.replaceRange( null,start,end);
}
});
menuIt7.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
transferable=clipboard.getContents(this);
flavor=DataFlavor.stringFlavor;
if (transferable.isDataFlavorSupported(flavor)) {
int start=testArea.getSelectionStart();
int end=testArea.getSelectionEnd();
testArea.replaceRange( null,start,end);
int pos=testArea.getCaretPosition();
try {
str=(String)transferable.getTransferData(flavor);
testArea.insert(str, pos);
} catch (UnsupportedFlavorException e1) {
e1.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
}
}
}
});
menuIt8.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(null,"功能简单，绝对原创 ");
}
});
return pane;
}
JTextArea testArea;
private JScrollPane createAreaPane() {
JScrollPane pane = new JScrollPane();
pane.setBorder(new TitledBorder("编辑区域"));
testArea = new JTextArea();
testArea.setFont(new Font("宋体", Font.BOLD, 13));
testArea.setLineWrap(true);
pane.getViewport().add(testArea);
return pane;
}
public static void main(String[] args) {
TestDemo td = new TestDemo();
td.setVisible(true);
}
}
1. 新建一个记事本，后缀名是 .java ；然后在里面写一段java的代码，如图：
2.把写好的java文件丢进D盘，就是第一步给出的那个class文件；
3. 打开dos界面 开始-〉运行-〉cmd-〉 这个是命令行模式,选择D盘，如图：
4.选择D盘之后，在命令提示符中输入“javac 文件名.java”,我的文件名为java，所以输入javac java.java然后回车，等待编译。这时候你就会发现它提示说javac不是内部文件。接下来就是java环境变量设置的问题了；
5.下载一个jdk执行默认安装。例如我下的jdk版本是： jdk-6u10-rc2-bin-b32-windows-i586-p-12_sep_2008.exe；
6.配置环境：右击我的电脑点属性，进去点高级就能看到环境变量。点进去就能设置你的系统变量了，如图：
6-1。变量名：classpath 变量值：(.;C:\Program Files\Java\jdk1.6.0_10\lib;)括号里面都是 （主要我们在编译运行程序的时候通过classpath可以帮助我们找到一些需要的系统类，“.”号是表示当前路径；“;”号是用来隔开多个变量值，如果你的系统里面已经有classpath环 境变量，就不用新建了，直接加“;”号，在后面加新值）；如图所示
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) {
}
}
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