java简单记事本

import javax.swing.*; import java.awt.event.*; import java.io.*; public class TestTxt extends JFrame{ File file = null; JTextPane text = new JTextPane(); static JMenuBar menubar = new JMenuBar(); JFileChooser filechooser = new JFileChooser(); void inTextPane() { getContentPane().add(new JScrollPane(text)); } JMenu[] menus = new JMenu[] { new JMenu("文件"),new JMenu("编辑"),new JMenu("帮助") }; JMenuItem menuitems[][] = new JMenuItem[][] { { new JMenuItem("新建"),new JMenuItem("打开"),new JMenuItem("保存"),new JMenuItem("退出") }, { new JMenuItem("复制"),new JMenuItem("剪切"),new JMenuItem("粘贴") }, { new JMenuItem("关于") } }; void inMenu() { for (int i = 0;i < menus.length; i ++) { menubar.add(menus[i]); for(int j = 0; j < menuitems[i].length; j ++) { menus[i].add(menuitems[i][j]); menuitems[i][j].addActionListener(action); } } //this.setJMenuBar(menubar); } ActionListener action = new ActionListener() { public void actionPerformed(ActionEvent e) { JMenuItem mi = (JMenuItem)e.getSource(); String id = mi.getText(); if(id.equals("新建")) { text.setText("sorry!此功能尚不支持！"); file = null; }else if(id.equals("打开")) { if(file != null) filechooser.setSelectedFile(file); int returnVal = filechooser.showOpenDialog(null); if(returnVal == JFileChooser.APPROVE_OPTION) { file = filechooser.getSelectedFile(); openFile(); } }else if(id.equals("保存")) { if(file != null) filechooser.setSelectedFile(file); int returnVal = filechooser.showSaveDialog(null); if(returnVal == JFileChooser.APPROVE_OPTION) { file = filechooser.getSelectedFile(); saveFile(); } }else if(id.equals("退出")) { TestTxt txt = new TestTxt(); int s = JOptionPane.showConfirmDialog(txt, "你真的要退出吗？"); if(s ==JOptionPane.YES_OPTION) System.exit(0); }else if(id.equals("剪切")) { text.cut(); }else if(id.equals("复制")) { text.copy(); }else if(id.equals("粘贴")) { text.paste(); }else if(id.equals("关于")) { TestTxt txt = new TestTxt(); JDialog dialog = new JDialog(txt,"help"); dialog.getContentPane().add(new JLabel(" 测试版本（by_xgc)")); dialog.setSize(200,150); dialog.setVisible(true); } } private void saveFile() { // TODO 自动生成方法存根 try { FileWriter fw = new FileWriter(file); fw.write(text.getText()); fw.close(); }catch(Exception e) { e.printStackTrace(); } } private void openFile() { try { FileReader fr = new FileReader(file); int len = (int)file.length(); char[] mu = new char[len]; fr.read(mu, 0, len); fr.close(); text.setText(new String(mu)); }catch(Exception e) { e.printStackTrace(); } } }; TestTxt() { inTextPane(); inMenu(); } public static void main(String[] args) { TestTxt txt = new TestTxt(); //txt.setLayout(new FlowLayout()); txt.setVisible(true); txt.setSize(800,600); txt.setTitle("记事本"); txt.addWindowListener( new WindowAdapter() { public void windowClosing(WindowEvent e) { TestTxt txt = new TestTxt(); int s = JOptionPane.showConfirmDialog(txt, "你真的要结束吗？"); if (s == JOptionPane.YES_OPTION) System.exit(0); } } ); txt.setJMenuBar(menubar); txt.show(); } }