java模仿window平台的NotePad，编写的一个简单的“记事本”程序

/* * To change this template, choose Tools | Templates * and open the template in the editor. */ /** * * @author Administrator */ 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.JFileChooser; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JOptionPane; import javax.swing.JScrollPane; import javax.swing.JTextArea; import javax.swing.filechooser.FileFilter; public class NotePad extends JFrame { private static final long serialVersionUID = 1L; //Eclipse自动生成序列号 String name = "无标题"; JTextArea text = new JTextArea(); //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)"); JMenuItem[] mniServers = new JMenuItem[]{ new JMenuItem("新建(N)"), new JMenuItem("保存(S)"), new JMenuItem("打开(O)"), new JMenuItem("退出(X)"), }; { mnbMain.add(mnServer); 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 NotePad(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) { while(name.equals("无标题")){ String input = JOptionPane.showInputDialog(mniServers[0],"输入文件名(后缀为txt、c或java)").toLowerCase(); if(input.endsWith(".txt")||input.endsWith(".c") || input.endsWith(".java")) { name = input; } } write(text.getText(),name); NotePad.this.setTitle( name +" - 记事本"); JOptionPane.showConfirmDialog(NotePad.this, "文件已经存入C:/Documents and Settings/Administrator/桌面 下"); } }); mniServers[2].addActionListener(new ActionListener() { //定义"打开"组件操作 @Override public void actionPerformed(ActionEvent arg0) { 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"); } name = chooser.getSelectedFile().getName(); NotePad.this.setTitle( name +" - 记事本"); read(chooser.getSelectedFile()); } }); mniServers[3].addActionListener(new ActionListener() { //定义"退出"组件操作 @Override public void actionPerformed(ActionEvent arg0) { System.exit(0); } }); } public NotePad() { this(200,200); } public NotePad(int x,int y) { this.setTitle( name +" - 记事本"); this.setBounds(x, y, 600, 400); this.setLayout(null); this.add(mnbMain); mnbMain.setBounds(5, 0, 50, 30); this.add(jsp); jsp.setBounds(5, 30, getWidth()-10, getHeight()-50); this.setDefaultCloseOperation(DISPOSE_ON_CLOSE); this.setVisible(true); } /*********************************************MAIN**************************************************/ public static void main(String[] args) { new NotePad(); } private void read(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(); } } private void write(String txt,String fileName){ FileWriter fw; try { fw = new FileWriter("C:/Documents and Settings/Administrator/桌面/"+fileName); BufferedWriter bw = new BufferedWriter(fw); bw.write(txt); bw.flush(); bw.close(); fw.close(); } catch (IOException e) { e.printStackTrace(); } } }