java简易记事本代码,java简单记事本代码

记事本java代码

//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

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语言编写一个记事本程序

import java.awt.*;

import java.awt.event.*;

import java.io.FileReader;

import java.io.FileWriter;

import javax.swing.JFileChooser; import java.awt.*;

import java.awt.event.*;

import java.io.FileReader;

import java.io.FileWriter;

import javax.swing.JFileChooser;

public class TextEditor extends Frame implements ActionListener{

MenuBar mainmenubar=new MenuBar();

Menu file;

MenuItem nw;

MenuItem op;

MenuItem cl;

MenuItem sf;

MenuItem ex;

TextArea tx;

public TextEditor(String title){

super(title);

CloseHandler handler= new CloseHandler();

this.addWindowListener(handler);

setSize(400,400);

setLocationRelativeTo(null);

menuinit();

tx=new TextArea();

this.add(tx);

setVisible(true);

}

void menuinit(){

mainmenubar =new MenuBar();

file=new Menu("File");

nw=new MenuItem("Great");

op=new MenuItem("Open");

cl=new MenuItem("Close");

sf=new MenuItem("save");

ex=new MenuItem("Exit");

file.add(nw);

file.add(op);

file.add(cl);

file.add(sf);

file.add(ex);

mainmenubar.add(file);

setMenuBar(mainmenubar);

nw.addActionListener(this);

op.addActionListener(this);

cl.addActionListener(this);

sf.addActionListener(this);

ex.addActionListener(this);

}

public void actionPerformed(ActionEvent e){

Object ob=e.getSource();

JFileChooser f =new JFileChooser();

if((ob==nw)||(ob==ex)){

tx.setText("write word in here");

}else if(ob==op){

f.showOpenDialog(this);

try{

StringBuffer s=new StringBuffer();

FileReader in=new FileReader(f.getSelectedFile());

while(true){

int b=in.read();

if(b==-1)

break;

s.append((char)b);

}

String myString=s.toString();

char[] mychar=myString.toCharArray();

String unkeyFile =FileEncry(mychar);

tx.setText(unkeyFile.toString());

in.close();

}catch(Exception ee){

}

}else if(ob==sf){

f.showSaveDialog(this);

try{

FileWriter out =new FileWriter(f.getSelectedFile());

String mystr=tx.getText();

char[] strchar=mystr.toCharArray();

String keyFile =FileEncry(strchar);

out.write(keyFile);

out.close();

}catch (Exception ee){

}

}else if(ob==ex)

System.exit(0);

}

public static void main(String[] args){

new TextEditor("Simple TextEdit");

}

public String FileEncry(char[] encry){

StringBuffer str=new StringBuffer();

char[] encry1 =new char[encry.length];

for(int i=0; iencry.length;i++){

encry1[i]=(char) (encry[i]^'F');

str.append(encry1[i]);

}

return str.toString();

}

}

class CloseHandler extends WindowAdapter{

public void windowClosing(WindowEvent e){

System.exit(0);

}

}

Q3: java简单记事本源代码 带解释

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import javax.swing.border.*;

class test implements ActionListener

{

JFrame frame;

JButton b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,b15,b16,b17,b18,b19,b20,b21,b22,b23,b24,b25,b26,b27,b28,b29,b30,b31;

JTextArea ta;

JPanel p1,p2,p3,p4;

JMenuBar mb;

JMenu m1,m2,m3;

JMenuItem mt1,mt2,mt3,mt4,mt5,mt6,mt7;

JRadioButton rb1,rb2;

ButtonGroup bg;

Double d1=0.0,d2=0.0,d3=0.0,d4=1.0,d5=1.0;

String s1="",s2="",s3="",s4="";

int a=0;

char c1;

int i=0;

public static void main(String[] args)

{

test that=new test();

that.go();

}

public void go()

{

frame=new JFrame("计算器");

Container cp= frame.getContentPane();

cp.setLayout(new FlowLayout());

b1=new JButton("7");b2=new JButton("8");b3=new JButton("9");b4=new JButton("/");b5=new JButton("1/x");b6=new JButton("sin");b7=new JButton("log");

b8=new JButton("4");b9=new JButton("5");b10=new JButton("6");b11=new JButton("*");b12=new JButton("x^y");b13=new JButton("cos");b14=new JButton("ln");

b15=new JButton("1");b16=new JButton("2");b17=new JButton("3");b18=new JButton("-");b19=new JButton(new ImageIcon("lanying.gif"));b20=new JButton("tan");b21=new JButton("x^3");

b22=new JButton("0");b23=new JButton("+/-");b24=new JButton(".");b25=new JButton("+");b26=new JButton("√x");b27=new JButton("cot");b28=new JButton("x^2");

b29=new JButton("Backspace");b30=new JButton("C");b31=new JButton("=");

mb=new JMenuBar();

m1=new JMenu("文件(F)");m2=new JMenu("编辑(E)");m3=new JMenu("帮助(H)");

mt1=new JMenuItem("清零");mt2=new JMenuItem("退出");mt3=new JMenuItem("复制");mt4=new JMenuItem("粘贴");mt5=new JMenuItem("版本");mt6=new JMenuItem("标准型");mt7=new JMenuItem("科学型");

ta=new JTextArea(1,30);

p1=new JPanel();p2=new JPanel();p3=new JPanel();p4=new JPanel();

rb1=new JRadioButton("科学型");rb2=new JRadioButton("标准型");

bg=new ButtonGroup();

b1.setForeground(Color.blue);b1.setBackground(Color.white);b2.setForeground(Color.blue);b2.setBackground(Color.white);

b3.setForeground(Color.blue);b3.setBackground(Color.white);b8.setForeground(Color.blue);b8.setBackground(Color.white);

b9.setForeground(Color.blue);b9.setBackground(Color.white);b10.setForeground(Color.blue);b10.setBackground(Color.white);

b15.setForeground(Color.blue);b15.setBackground(Color.white);b16.setForeground(Color.blue);b16.setBackground(Color.white);

b17.setForeground(Color.blue);b17.setBackground(Color.white);b22.setForeground(Color.blue);b22.setBackground(Color.white);

b23.setForeground(Color.blue);b23.setBackground(Color.white);b24.setForeground(Color.blue);b24.setBackground(Color.white);

b4.setForeground(Color.red);b4.setBackground(Color.white);b11.setForeground(Color.red);b11.setBackground(Color.white);

b18.setForeground(Color.red);b18.setBackground(Color.white);b25.setForeground(Color.red);b25.setBackground(Color.white);

b5.setForeground(Color.blue);b5.setBackground(Color.white);b6.setForeground(Color.blue);b6.setBackground(Color.white);

b7.setForeground(Color.blue);b7.setBackground(Color.white);b12.setForeground(Color.blue);b12.setBackground(Color.white);

b13.setForeground(Color.blue);b13.setBackground(Color.white);b14.setForeground(Color.blue);b14.setBackground(Color.white);

b19.setForeground(Color.blue);b19.setBackground(Color.white);b20.setForeground(Color.blue);b20.setBackground(Color.white);

b21.setForeground(Color.blue);b21.setBackground(Color.white);b26.setForeground(Color.blue);b26.setBackground(Color.white);

b27.setForeground(Color.blue);b27.setBackground(Color.white);b28.setForeground(Color.blue);b28.setBackground(Color.white);

b29.setForeground(Color.red);b29.setBackground(Color.white);b30.setForeground(Color.red);b30.setBackground(Color.white);

b31.setForeground(Color.red);b31.setBackground(Color.white);

bg.add(rb1);bg.add(rb2);

p1.setBackground(Color.yellow);

cp.setBackground(Color.CYAN);

m1.setMnemonic(KeyEvent.VK_F);m2.setMnemonic(KeyEvent.VK_E);m3.setMnemonic(KeyEvent.VK_H);

m1.add(mt6);m1.add(mt7);m1.addSeparator();m1.add(mt1);m1.addSeparator();m1.add(mt2);m2.add(mt3);m2.addSeparator();m2.add(mt4);m3.add(mt5);

mb.add(m1);mb.add(m2);mb.add(m3);

frame.setJMenuBar(mb);

p2.setLayout(new GridLayout(4,7));

p3.setLayout(new GridLayout(1,3));

ta.setEditable(false);

p1.add(ta);

p2.add(b1);p2.add(b2);p2.add(b3);p2.add(b4);p2.add(b5);p2.add(b6);p2.add(b7);

p2.add(b8);p2.add(b9);p2.add(b10);p2.add(b11);p2.add(b12);p2.add(b13);p2.add(b14);

p2.add(b15);p2.add(b16);p2.add(b17);p2.add(b18);p2.add(b19);p2.add(b20);p2.add(b21);

p2.add(b22);p2.add(b23);p2.add(b24);p2.add(b25);p2.add(b26);p2.add(b27);p2.add(b28);

p3.add(b29);p3.add(b30);p3.add(b31);

Border etched=BorderFactory.createEtchedBorder();

Border border=BorderFactory.createTitledBorder(etched,"计算类型");

p4.add(rb1);p4.add(rb2);

p4.setBorder(border);

b2.setActionCommand("8");

b2.addActionListener(this);

cp.add(p1);cp.add(p4);cp.add(p2);cp.add(p3);

frame.setSize(400,330);

frame.setVisible(true);

frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

b1.setActionCommand("7");

b1.addActionListener(this);

b2.setActionCommand("8");

b2.addActionListener(this);

b3.setActionCommand("9");

b3.addActionListener(this);

b4.setActionCommand("/");

b4.addActionListener(this);

b5.setActionCommand("1/x");

b5.addActionListener(this);

b6.setActionCommand("sin");

b6.addActionListener(this);

b7.setActionCommand("log");

b7.addActionListener(this);

b8.setActionCommand("4");

b8.addActionListener(this);

b9.setActionCommand("5");

b9.addActionListener(this);

b10.setActionCommand("6");

b10.addActionListener(this);

b11.setActionCommand("*");

b11.addActionListener(this);

b12.setActionCommand("x^y");

b12.addActionListener(this);

b13.setActionCommand("cos");

b13.addActionListener(this);

b14.setActionCommand("ln");

b14.addActionListener(this);

b15.setActionCommand("1");

b15.addActionListener(this);

b16.setActionCommand("2");

b16.addActionListener(this);

b17.setActionCommand("3");

b17.addActionListener(this);

b18.setActionCommand("-");

b18.addActionListener(this);

b19.setActionCommand("x!");

b19.addActionListener(this);

b20.setActionCommand("tan");

b20.addActionListener(this);

b21.setActionCommand("x^3");

b21.addActionListener(this);

b22.setActionCommand("0");

b22.addActionListener(this);

b23.setActionCommand("+/-");

b23.addActionListener(this);

b24.setActionCommand(".");

b24.addActionListener(this);

b25.setActionCommand("+");

b25.addActionListener(this);

b26.setActionCommand("√x");

b26.addActionListener(this);

b27.setActionCommand("cot");

b27.addActionListener(this);

b28.setActionCommand("x^2");

b28.addActionListener(this);

b29.setActionCommand("Backspace");

b29.addActionListener(this);

b30.setActionCommand("C");

b30.addActionListener(this);

b31.setActionCommand("=");

b31.addActionListener(this);

rb1.setActionCommand("kxx");

rb1.addActionListener(this);

rb2.setActionCommand("bzx");

rb2.addActionListener(this);

}

public void actionPerformed(ActionEvent e) //throws Exception

{

if (e.getActionCommand()=="bzx")

{

b5.setEnabled(false);b6.setEnabled(false);b7.setEnabled(false);

b12.setEnabled(false);b13.setEnabled(false);b14.setEnabled(false);

b19.setEnabled(false);b20.setEnabled(false);b21.setEnabled(false);

b26.setEnabled(false);b27.setEnabled(false);b28.setEnabled(false);

}

if (e.getActionCommand()=="kxx")

{

b5.setEnabled(true);b6.setEnabled(true);b7.setEnabled(true);

b12.setEnabled(true);b13.setEnabled(true);b14.setEnabled(true);

b19.setEnabled(true);b20.setEnabled(true);b21.setEnabled(true);

b26.setEnabled(true);b27.setEnabled(true);b28.setEnabled(true);

}

if (e.getActionCommand()=="1")

{

ta.append("1");

}

if (e.getActionCommand()=="2")

{

ta.append("2");

}

if (e.getActionCommand()=="3")

{

ta.append("3");

}

if (e.getActionCommand()=="4")

{

ta.append("4");

}

if (e.getActionCommand()=="5")

{

ta.append("5");

}

if (e.getActionCommand()=="6")

{

ta.append("6");

}

if (e.getActionCommand()=="7")

{

ta.append("7");

}

if (e.getActionCommand()=="8")

{

ta.append("8");

}

if (e.getActionCommand()=="9")

{

ta.append("9");

}

if (e.getActionCommand()=="0")

{

ta.append("0");

}

if (e.getActionCommand()=="+")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

ta.setText("");

i=1;

}

if (e.getActionCommand()=="-")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

ta.setText("");

i=2;

}

if (e.getActionCommand()=="*")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

ta.setText("");

i=3;

}

if (e.getActionCommand()=="/")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

ta.setText("");

i=4;

}

if (e.getActionCommand()=="=")

{

s2=ta.getText();

d2=Double.parseDouble(s2);

if(i==1)

{

d3=d1+d2;

ta.setText( d3.toString());

}

if(i==2)

{

d3=d1-d2;

ta.setText( d3.toString());

}

if(i==3)

{

d3=d1*d2;

ta.setText( d3.toString());

}

if(i==4)

{

if(d2==0.0)

ta.setText("ERROR");

else

{

d3=d1/d2;

ta.setText( d3.toString());

}

}

if (i==5)

{

s2=ta.getText();

d2 = Double.parseDouble(s2);

for (int l=1;l=d2 ; l++)

{

d5=d5*d1;

}

ta.setText( d5.toString());

}

}

if (e.getActionCommand()=="C")

{

ta.setText("");

d4=1.0;

d5=1.0;

}

/*if (e.getActionCommand()=="Backspace")

{

s3=ta.getText();

a=s3.length();

//ta.cut(ta.select(a-1,a));

s4=ta.getText(1,3);

ta.setText(s4);

}

*/

if (e.getActionCommand()=="1/x")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

d2=1/d1;

ta.setText( d2.toString());

}

if (e.getActionCommand()==".")

{

ta.append(".");

}

if (e.getActionCommand()=="+/-")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

d2=0-d1;

ta.setText( d2.toString());

}

if (e.getActionCommand()=="x^2")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

d2=d1*d1;

ta.setText( d2.toString());

}

if (e.getActionCommand()=="x^3")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

d2=d1*d1*d1;

ta.setText( d2.toString());

}

if (e.getActionCommand()=="x^y")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

ta.setText("");

i=5;

// d2=d1*d1*d1;

// ta.setText( d2.toString());

}

if (e.getActionCommand()=="√x")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

d2=Math.sqrt(d1);

ta.setText( d2.toString());

}

if (e.getActionCommand()=="x!")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

if (d10)

{

ta.setText( "error");

}

else if (d1==0)

{

ta.setText( "0.0");

}

else {

for (int k=1;k=d1 ;k++ )

d4=d4*k;

ta.setText( d4.toString());

}

}

if (e.getActionCommand()=="sin")

{

s1=ta.getText();

d1 = Double.parseDouble(s1);

d2=Math.sin(3.1415926*d1/180);

ta.setText( d2.toString());

}

}

}

Q4: 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();}}

Q5: 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) {

}

}