java简易编辑器

package peng_jun;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import java.util.*;
import java.io.*;
import javax.swing.filechooser.*;
import javax.swing.filechooser.FileFilter;
import java.awt.datatransfer.*;

public class Text extends JFrame {
    TextArea area;//文本域
    String name = null;//文件名
    String board = null;
    private Clipboard cb;//系统粘贴板

    Text() throws Exception {//构造函数
        setTitle("记事本");
        Toolkit kit = Toolkit.getDefaultToolkit();//Toolkit获得本机系统的屏幕的参数
        //Image img = kit.getImage("01.jpg");
        //setIconImage(img);
        
        
        JMenuBar jmb = new JMenuBar();//创建菜单条
        add(jmb);
        setJMenuBar(jmb);
        area = new TextArea();
        add(area);
        
        JMenu file = new JMenu("文件");//定义“文件”菜单项
        JMenuItem rebuild = new JMenuItem("新建");
        rebuild.setAccelerator(KeyStroke.getKeyStroke("ctrl N"));
        JMenuItem save = new JMenuItem("保存");
        save.setAccelerator(KeyStroke.getKeyStroke("ctrl S"));
        JMenuItem open = new JMenuItem("打开");
        open.setAccelerator(KeyStroke.getKeyStroke("ctrl O"));
        JMenuItem anotherSave = new JMenuItem("另存为");
        file.add(rebuild);
        file.add(save);
        file.add(open);
        file.add(anotherSave);
        // JScrollPane scroldPane=new JScrollPane(area); //设置滚动轴
        // add(scroldPane);
        JMenu edit = new JMenu("编辑");//定义“编辑”菜单项
        JMenuItem cut = new JMenuItem("剪切");
        cut.setAccelerator(KeyStroke.getKeyStroke("ctrl X"));
        JMenuItem copy = new JMenuItem("复制");
        copy.setAccelerator(KeyStroke.getKeyStroke("ctrl C"));
        JMenuItem plaster = new JMenuItem("粘贴");
        plaster.setAccelerator(KeyStroke.getKeyStroke("ctrl V"));
        JMenuItem all = new JMenuItem("全选");
        all.setAccelerator(KeyStroke.getKeyStroke("ctrl A"));
        edit.add(cut);
        edit.add(copy);
        edit.add(plaster);
        edit.add(all);
        JMenu help = new JMenu("帮助");//定义“帮助”菜单项
        JMenuItem about = new JMenuItem("关于");
        help.add(about);
        
        jmb.add(file);
        jmb.add(edit);
        jmb.add(help);
        setSize(600, 400);
        //setLocation(300, 200);
        setVisible(true);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        cb = Toolkit.getDefaultToolkit().getSystemClipboard();//调用系统剪贴板
        save.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                try {
                    saveText();
                } catch (Exception ex) {
                }
            }
        });
        open.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                try {
                    openText();
                } catch (Exception ex) {
                }
            }
        });
        rebuild.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                try {
                    area.setText("");
                    name = null;
                } catch (Exception ex) {
                }
            }
        });
        anotherSave.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                anotherSaveText();
            }
        });
        
        cut.addActionListener(new ActionListener() // 剪切
        {
            public void actionPerformed(ActionEvent e) {
                board = area.getSelectedText();
                cb.setContents(new StringSelection(board), null);
                area.replaceRange("", area.getSelectionStart(),
                        area.getSelectionEnd());
            }
        });
        copy.addActionListener(new ActionListener() // 复制
        {
            public void actionPerformed(ActionEvent e) {
                board = area.getSelectedText();
                cb.setContents(new StringSelection(board), null);
            }
        });
        plaster.addActionListener(new ActionListener() // 粘贴
        {
            public void actionPerformed(ActionEvent e) {
                try {
                    Transferable content = cb.getContents(null);
                    String st = (String) content
                            .getTransferData(DataFlavor.stringFlavor);
                    area.replaceRange(st, area.getSelectionStart(),
                            area.getSelectionEnd());
                } catch (Exception ex) {
                }
            }
        });
        all.addActionListener(new ActionListener() // 全选
        {
            public void actionPerformed(ActionEvent e) {
                area.setSelectionStart(0);
                area.setSelectionEnd(area.getText().length());
            }
        });
        about.addActionListener(new ActionListener() {//帮助
            public void actionPerformed(ActionEvent e) {
                JFrame frame = new JFrame("关于");
                frame.setSize(150, 100);
                frame.setLocation(400, 300);
                JTextArea area1 = new JTextArea("java简易文本编辑器");
                frame.add(area1);
                frame.setVisible(true);
            }
        });
    }

    public void openText() // 打开
    {
        JFileChooser chooser = new JFileChooser();
        FileNameExtensionFilter filter = new FileNameExtensionFilter("Files",
                "txt", "java");
        chooser.setFileFilter(filter);
        chooser.setCurrentDirectory(new File("."));
        int result = chooser.showOpenDialog(Text.this);
        if (result == JFileChooser.APPROVE_OPTION) {
            name = chooser.getSelectedFile().getPath();
            setTitle(name);
            try {
                BufferedReader in = new BufferedReader(new FileReader(name));
                String line = null;
                String datas = "";
                while ((line = in.readLine()) != null) {
                    if (datas == "") {
                        datas = datas + line;
                    } else {
                        datas = datas + "
" + line;
                    }
                }
                area.setText(datas);
                in.close();
            } catch (Exception ex) {
            }
        }
    }

    public void saveText() // 保存
    {
        if (name == null) {
            JFileChooser chooser = new JFileChooser();
            FileNameExtensionFilter filter = new FileNameExtensionFilter(
                    "Files", "txt", "java");
            chooser.setFileFilter(filter);
            chooser.setCurrentDirectory(new File("."));
            int result = chooser.showSaveDialog(Text.this);
            if (result == JFileChooser.APPROVE_OPTION) {
                name = chooser.getSelectedFile().getPath();
                try {
                    OutputStream out = new FileOutputStream(name);
                    String datas = area.getText();
                    out.write(datas.getBytes());
                    out.close();
                } catch (Exception ex) {
                }
            }
        } else {
            try {
                OutputStream out = new FileOutputStream(name);
                String datas = area.getText();
                out.write(datas.getBytes());
                out.close();
            } catch (Exception ex) {
            }
        }
    }

    public void anotherSaveText() // 另存为
    {
        JFileChooser chooser = new JFileChooser();
        FileNameExtensionFilter filter = new FileNameExtensionFilter("Files",
                "txt", "java");
        chooser.setFileFilter(filter);
        chooser.setCurrentDirectory(new File("."));
        int result = chooser.showSaveDialog(Text.this);
        if (result == JFileChooser.APPROVE_OPTION) {
            name = chooser.getSelectedFile().getPath();
            try {
                OutputStream out = new FileOutputStream(name);
                String datas = area.getText();
                out.write(datas.getBytes());
                out.close();
            } catch (Exception ex) {
            }
        }
    }

    public static void main(String[] args) throws Exception {
        new Text();
    }
}