import java.util.Scanner;
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import java.awt.*;
import java.awt.event.*;
public class Test extends WindowAdapter {
Panel p1 = new Panel();
Panel p2 = new Panel();
Panel p3 = new Panel();
TextField txt;
private Button[] b = new Button[17];
private String ss[] = { "7", "8", "9", "+", "4", "5", "6", "-", "1", "2",
"3", "*", "clear", "0", "=", "/", "close" };
static double a;
static String s, str;// 定义变量 创建对像
public static void main(String args[]) {
(new Test()).frame();
}
public void frame() {
Frame fm = new Frame("简单计算器");
for (int i = 0; i = 16; i++) {
b[i] = new Button(ss[i]);
}
for (int i = 0; i = 15; i++) {
p2.add(b[i]);
} // 创建按钮 并添加到P2
b[16].setBackground(Color.yellow);
txt = new TextField(15);
txt.setEditable(false);
for (int i = 0; i = 16; i++) {
b[i].addActionListener(new buttonlistener());// 添加监听器
}
b[16].addActionListener(new close());
fm.addWindowListener(this);
fm.setBackground(Color.red);
p1.setLayout(new BorderLayout());
p1.add(txt, "North");
p2.setLayout(new GridLayout(4, 4));
p3.setLayout(new BorderLayout());
p3.add(b[16]);
fm.add(p1, "North");
fm.add(p2, "Center");
fm.add(p3, "South");
fm.pack();
fm.setVisible(true);// 都是些窗中设置 添加相关组件和监听器
}
public void windowClosing(WindowEvent e) {
System.exit(0);// 退出系统
}
class buttonlistener implements ActionListener {// 编写监听器事件 通过按键得出给果
public void actionPerformed(ActionEvent e) {
Button btn = (Button) e.getSource();
if (btn.getLabel() == "=") {
jisuan();
str = String.valueOf(a);
txt.setText(str);
s = "";
} else if (btn.getLabel() == "+") {
jisuan();
txt.setText("");
s = "+";
} else if (btn.getLabel() == "-") {
jisuan();
txt.setText("");
s = "-";
} else if (btn.getLabel() == "/") {
jisuan();
txt.setText("");
s = "/";
} else if (btn.getLabel() == "*") {
jisuan();
txt.setText("");
s = "*";
} else {
txt.setText(txt.getText() + btn.getLabel());
if (btn.getLabel() == "clear")
txt.setText("");
}
}
public void jisuan() {// 编写具体计算方法
if (s == "+")
a += Double.parseDouble(txt.getText());
else if (s == "-")
a -= Double.parseDouble(txt.getText());
else if (s == "*")
a *= Double.parseDouble(txt.getText());
else if (s == "/")
a /= Double.parseDouble(txt.getText());
else
a = Double.parseDouble(txt.getText());
}
}
}
class close implements ActionListener {// 退出
public void actionPerformed(ActionEvent e) {
System.exit(0);
}
}
package example;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
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.border.EmptyBorder;
public class demo extends JFrame{
private JMenuBar menu = new JMenuBar();
private JPanel contentPane = new JPanel();
public demo()
{
setTitle("compiler");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setJMenuBar(menu);
//JMenu correct = new JMenu("正确用例");
//JMenu wrong = new JMenu("错误用例");
////JMenuItem WP = wrong.add("语法错误");
//JMenuItem WL = wrong.add("词法错误");
JMenu edit = new JMenu("编辑");
JMenu help = new JMenu("帮助");
JMenu document = new JMenu("文件");
JMenuItem copy = edit.add("复制");
JMenu color = new JMenu("颜色");
JMenuItem p = color.add("前景色");
p.addActionListener(new ActionListener()
{
@Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(null,
"该项目正在建设中", "信息",
JOptionPane.INFORMATION_MESSAGE);
}
});
JMenuItem b = color.add("背景色");
b.addActionListener(new ActionListener()
{
@Override
public void actionPerformed(ActionEvent e) {
JOptionPane.showMessageDialog(null,
"该项目正在建设中", "信息",
JOptionPane.INFORMATION_MESSAGE);
}
});
edit.add(color);
JMenuItem select = edit.add("全选");
menu.add(document);
menu.add(edit);
menu.add(help);
setLocation(400,200);
setSize(300, 300);
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
}
public static void main(String[]args)
{
demo browser = new demo();
browser.setVisible(true);
}
}
java设计计算器，主要是使用java swing，对每个按钮进行监听，实现相关功能，如下代码：
package com.qiu.lin.he;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingConstants;
public class Jisuanqi extends JFrame implements ActionListener {
/**
*
*/
private static final long serialVersionUID = 1L;
Result result = new Result(); // 定义text的面板
Number_Key number_key = new Number_Key(); // 定义按钮面板
// 当点击按钮+、-、*、/时，com = true
boolean com = false;
// 当i=0时说明是我们第一次输入，字符串text不会累加
int i = 0;
// 存放text的内容
String text = "";
// 存放点击按钮+、-、*、/之前的数值
double defbutton = 0;
// +、-、*、/的代号分别为1，2，3，4
int symbol = 0;
// 构造函数
Jisuanqi() {
super("WangJiao"); // 设定标题
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // 设定关闭窗体时退出程序
JPanel pane = new JPanel(); // 定义主面板
pane.setLayout(new BorderLayout());
setBounds(380, 220, 30, 80); // 前两个参数是在屏幕上显示的坐标，后两个是大小
// 替换图标
ImageIcon icon = new ImageIcon("F:1.GIF");
// Jisuanqi.class.getResource("APPLE.GIF")
// );
setIconImage(icon.getImage());
pane.add(result, BorderLayout.NORTH);
pane.add(number_key, BorderLayout.CENTER);
pane.add(number_key.equal, BorderLayout.SOUTH);
number_key.one.addActionListener(this); // 对1按钮添加监听事件
number_key.two.addActionListener(this); // 对2按钮添加监听事件
number_key.three.addActionListener(this); // 对3按钮添加监听事件
number_key.four.addActionListener(this); // 对4按钮添加监听事件
number_key.five.addActionListener(this); // 对5按钮添加监听事件
number_key.six.addActionListener(this); // 对6按钮添加监听事件
number_key.seven.addActionListener(this); // 对7按钮添加监听事件
number_key.eight.addActionListener(this); // 对8按钮添加监听事件
number_key.nine.addActionListener(this); // 对9按钮添加监听事件
number_key.zero.addActionListener(this); // 对0按钮添加监听事件
number_key.ce.addActionListener(this); // 对置零按钮添加监听事件
number_key.plus.addActionListener(this); // 对+按钮添加监听事件
number_key.equal.addActionListener(this); // 对=按钮添加监听事件
number_key.sub.addActionListener(this); // 对-按钮添加监听事件
number_key.mul.addActionListener(this); // 对*按钮添加监听事件
number_key.div.addActionListener(this); // 对/按钮添加监听事件
number_key.point.addActionListener(this); // 对.按钮添加监听事件
setContentPane(pane);
pack(); // 初始化窗体大小为正好盛放所有按钮
}
// 各个按钮触发的事件
public void actionPerformed(ActionEvent e) {
/*
* 如果是点击数字按钮那么先要判断是否在此之前点击了+、-、*、/、=，如果是那么com=true 如果没有com=
* false;或者是否点击数字键，如果是i = 1,如果没有 i = 0;
*/
if (e.getSource() == number_key.one) {
if (com || i == 0) {
result.text.setText("1");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "1");
}
} else if (e.getSource() == number_key.two) {
if (com || i == 0) {
result.text.setText("2");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "2");
}
} else if (e.getSource() == number_key.three) {
if (com || i == 0) {
result.text.setText("3");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "3");
}
} else if (e.getSource() == number_key.four) {
if (com || i == 0) {
result.text.setText("4");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "4");
}
} else if (e.getSource() == number_key.five) {
if (com || i == 0) {
result.text.setText("5");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "5");
}
} else if (e.getSource() == number_key.six) {
if (com || i == 0) {
result.text.setText("6");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "6");
}
} else if (e.getSource() == number_key.seven) {
if (com || i == 0) {
result.text.setText("7");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "7");
}
} else if (e.getSource() == number_key.eight) {
if (com || i == 0) {
result.text.setText("8");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "8");
}
} else if (e.getSource() == number_key.nine) {
if (com || i == 0) {
result.text.setText("9");
com = false;
i = 1;
} else {
text = result.text.getText();
result.text.setText(text + "9");
}
}
/*
* 对于0这个按钮有一定的说法，在我的程序里不会出现如00000这样的情况，我加了判断条件就是
* 如果text中的数值=0就要判断在这个数值中是否有.存在?如果有那么就在原来数值基础之上添 加0;否则保持原来的数值不变
*/
else if (e.getSource() == number_key.zero) { // result.text.getText()是得到text里内容的意思
if (com || i == 0) {
result.text.setText("0");
com = false;
i = 1;
} else {
text = result.text.getText();
if (Float.parseFloat(text) 0 || Float.parseFloat(text) 0) { // Float.parseFloat(text)就是类型转换了，下面都是一样
result.text.setText(text + "0");
} else {
if (text.trim().indexOf(".") == -1) {
result.text.setText(text);
} else {
result.text.setText(text + "0");
}
}
}
} else if (e.getSource() == number_key.ce) {
result.text.setText("0");
i = 0;
com = true;
// text = "";
defbutton = 0;
}
/*
* 本程序不会让一个数值中出现2个以上的小数点.具体做法是:判断是否已经存在.存在就不添加, 不存在就添加.
*/
else if (e.getSource() == number_key.point) {
if (com || i == 0) {
result.text.setText("0.");
com = false;
i = 1;
} else {
text = result.text.getText();
if (text.trim().indexOf(".") == -1) {
result.text.setText(text + ".");
} else {
result.text.setText(text);
}
}
} // 获得点击+之前的数值
else if (e.getSource() == number_key.plus) {
com = true;
i = 0;
defbutton = Double.parseDouble(result.text.getText());
symbol = 1;
} // 获得点击-之前的数值
else if (e.getSource() == number_key.sub) {
com = true;
i = 0;
defbutton = Double.parseDouble(result.text.getText());
symbol = 2;
} // 获得点击*之前的数值
else if (e.getSource() == number_key.mul) {
com = true;
i = 0;
defbutton = Double.parseDouble(result.text.getText());
System.out.println(defbutton);
symbol = 3;
} // 获得点击/之前的数值
else if (e.getSource() == number_key.div) {
com = true;
i = 0;
defbutton = Double.parseDouble(result.text.getText());
symbol = 4;
} else if (e.getSource() == number_key.equal) {
switch (symbol) {
case 1: { // 计算加法
double ad = defbutton
+ Double.parseDouble(result.text.getText());
result.text.setText(ad + "");
i = 0;
text = "";
break;
}
case 2: { // 计算减法
double ad = defbutton
- Double.parseDouble(result.text.getText());
result.text.setText(String.valueOf(ad));
i = 0;
text = "";
break;
}
case 3: { // 计算乘法
double ad = defbutton
* Double.parseDouble(result.text.getText());
result.text.setText(ad + "");
i = 0;
text = "";
break;
}
case 4: { // 计算除法
double ad = defbutton
/ Double.parseDouble(result.text.getText());
result.text.setText(ad + "");
i = 0;
text = "";
break;
}
}
System.out.println(com);
}
System.out.println(result.text.getText());
}
@SuppressWarnings("deprecation")
public static void main(String[] args) {
Jisuanqi loveyou = new Jisuanqi();
loveyou.show();
}
}
// 计算器数字按钮定义面板
class Number_Key extends JPanel {
/**
*
*/
private static final long serialVersionUID = 1L;
JButton zero = new JButton("0"); // 数字键0
JButton one = new JButton("1"); // 数字键1
JButton two = new JButton("2"); // 数字键2
JButton three = new JButton("3"); // 数字键3
JButton four = new JButton("4"); // 数字键4
JButton five = new JButton("5"); // 数字键5
JButton six = new JButton("6"); // 数字键6
JButton seven = new JButton("7"); // 数字键7
JButton eight = new JButton("8"); // 数字键8
JButton nine = new JButton("9"); // 数字键9
JButton plus = new JButton("+");
JButton sub = new JButton("-");
JButton mul = new JButton("*");
JButton div = new JButton("/");
JButton equal = new JButton("=");
JButton ce = new JButton("清零"); // 置零键
JButton point = new JButton(".");
Number_Key() {
setLayout(new GridLayout(4, 4, 1, 1)); // 定义布局管理器为网格布局
setBackground(Color.blue); // 设置背景颜色
// 添加按钮
add(one);
add(two);
add(three);
add(four);
add(five);
add(six);
add(seven);
add(eight);
add(nine);
add(zero);
add(plus);
add(sub);
add(mul);
add(div);
add(point);
add(equal);
add(ce);
}
}
// 计算器显示结果的窗体
class Result extends JPanel {
/**
*
*/
private static final long serialVersionUID = 1L;
// text先是输入和结果
JTextField text = new JTextField("0");
@SuppressWarnings("deprecation")
Result() { // 讲输入的数字或得到的结果在text的右边显示
text.setHorizontalAlignment(SwingConstants.RIGHT);
text.enable(false); // 文本框不能编辑
setLayout(new BorderLayout()); // 设定布局管理器边框布局
add(text, BorderLayout.CENTER); // text放置在窗体的中间
}
}
运行结果如下：
很简单的应用，为了节省字数，代码注释我就不加了
首先是显示层，LoinWindow：
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.border.EmptyBorder;
public class LoinWindow extends JFrame implements ActionListener, FocusListener {
private JPanel mainPanel, namePanel, btnPanel;
private JTextField tfName, tfPsd;
private JButton btnLogin, btnCancel;
private static final int WIDTH = 300;
private static final int HEIGHT = 200;
private LoginService service = new LoginService();
public LoinWindow() {
super("登录窗体");
}
public void launch() {
setSize(WIDTH, HEIGHT);
setVisible(true);
setDefaultCloseOperation(EXIT_ON_CLOSE);
GridLayout mainLayout = new GridLayout(2, 1);
mainLayout.setVgap(10);
mainPanel = new JPanel(mainLayout);
GridBagLayout nameLayout = new GridBagLayout();
namePanel = new JPanel(nameLayout);
namePanel.setBorder(new EmptyBorder(10, 10, 10, 10));
JLabel nameLabel = new JLabel("姓名：");
tfName = new JTextField();
JLabel psdLabel = new JLabel("密码：");
tfPsd = new JTextField();
JLabel blank = new JLabel(" ");
namePanel.add(nameLabel);
namePanel.add(tfName);
namePanel.add(blank);
namePanel.add(psdLabel);
namePanel.add(tfPsd);
GridBagConstraints s = new GridBagConstraints();
s.fill = GridBagConstraints.BOTH;
s.gridwidth = 1;
s.weightx = 0;
s.weighty = 0;
nameLayout.setConstraints(nameLabel, s);
s.gridwidth = 0;
s.weightx = 1;
s.weighty = 0;
nameLayout.setConstraints(tfName, s);
s.gridwidth = 0;
s.weightx = 4;
s.weighty = 0;
nameLayout.setConstraints(blank, s);
s.gridwidth = 1;
s.weightx = 0;
s.weighty = 0;
nameLayout.setConstraints(psdLabel, s);
s.gridwidth = 3;
s.weightx = 1;
s.weighty = 0;
nameLayout.setConstraints(tfPsd, s);
FlowLayout btnLayout = new FlowLayout();
btnLayout.setAlignment(FlowLayout.CENTER);
btnPanel = new JPanel(btnLayout);
btnLogin = new JButton("确定");
btnCancel = new JButton("取消");
btnPanel.add(btnLogin);
btnPanel.add(btnCancel);
btnCancel.addActionListener(this);
btnLogin.addActionListener(this);
mainPanel.add(namePanel);
mainPanel.add(btnPanel);
setContentPane(mainPanel);
tfName.addFocusListener(this);
tfPsd.addFocusListener(this);
pack();
setSize(WIDTH, HEIGHT);
setLocationRelativeTo(null);
}
@Override
public void actionPerformed(ActionEvent e) {
Object source = e.getSource();
if(source == btnCancel) {
System.exit(0);
} else if(source == btnLogin) {
String username = tfName.getText();
String password = tfPsd.getText();
boolean success = service.login(username, password);
if(success) {
warn("成功", "登录成功！");
} else {
warn("失败", "您输入的用户名或密码错误 ！");
}
}
}
@Override
public void focusGained(FocusEvent arg0) {
}
@Override
public void focusLost(FocusEvent e) {
Object source = e.getSource();
if(source == tfName) {
String username = tfName.getText();
try {
service.matchUsername(username);
} catch (LoginException e1) {
warn("验证错误", e1.getMessage());
}
} else if(source == tfPsd) {
String password = tfPsd.getText();
try {
service.matchPassword(password);
} catch (LoginException e1) {
warn("验证错误", e1.getMessage());
}
}
}
private void warn(String title, String msg) {
JOptionPane.showMessageDialog(null, msg, title, JOptionPane.INFORMATION_MESSAGE);
}
public static void main(String[] args) {
new LoinWindow().launch();
}
}
然后是模型层：LoginDao
public class LoginDao {
public boolean login(String username, String password) {
if(username.equals("admin") password.equals("12345")) {
return true;
}
return false;
}
}
LoginService
import java.util.regex.Pattern;
public class LoginService {
private static final Pattern LOGIN_PATTERN = Pattern.compile("[a-zA-Z]+");
private static final Pattern PASSWORD_PATTERN = Pattern.compile("[1-9]+");
private LoginDao dao = new LoginDao();
public boolean matchUsername(String username) throws LoginException {
if(null == username || username.isEmpty()) {
return false;
}
if(!LOGIN_PATTERN.matcher(username).matches()) {
throw new LoginException("您输入的用户名不合法，请输入英文！");
}
return true;
}
public boolean matchPassword(String password) throws LoginException {
if(null == password || password.isEmpty()) {
return false;
}
if(!PASSWORD_PATTERN.matcher(password).matches()) {
throw new LoginException("您输入的密码不合法，请输入数字！");
}
return true;
}
public boolean login(String username, String password) {
if(null == username || username.isEmpty()) {
return false;
}
if(null == password || password.isEmpty()) {
return false;
}
if(!dao.login(username, password)) {
return false;
}
return true;
}
}
LoginException
public class LoginException extends Exception {
public LoginException(String arg0) {
super(arg0);
}
}
不知道分层设计思想是不是我想的这样
import java.io.*;
public class FileLineNumber {
public static void main(String[] args) throws Exception {
appendLineNumber(new File("FileLineNumber.java"), new File("a.txt"));
}
public static void appendLineNumber(File from, File to) throws Exception {
BufferedReader in = new BufferedReader(new FileReader(from));
StringBuilder sb = new StringBuilder();
String t;
int lineNumber = 1;
while((t = in.readLine()) != null) {
sb.append(lineNumber + " ");
sb.append(t);
sb.append(System.getProperty("line.separator"));
lineNumber++;
}
in.close();
BufferedWriter out = new BufferedWriter(new FileWriter(to));
out.write(sb.toString());
out.close();
}
}