用Java编写的标准计算器、科学计算器、时间转换。

下面是我和我朋友编写的一个小程序，它们之间可以相互转换。

它们是我们通过参考网上的代码参考得来的。

下面有四个源文件，我都用----------帮你格开了。

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//时间转换

import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JTextArea;
import javax.swing.JTextField;

import java.awt.Color;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Stack;
import java.awt.event.ActionEvent;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;

import java.awt.Font;
import java.awt.GridLayout;

public class Calculator_Time extends JFrame implements ActionListener {

  private final String[] KEYS = { "7", "8", "9",   "4", "5", "6",
              "1", "2", "3",  "0", ".", "=",};
     /** 计算器上的功能键的显示名字      final p86*/
     private final String[] COMMAND = { "Backspace", "CE", "C" };
     /** 计算器左边的M的显示名字 */
     private final String[] M = {"小时化分钟","分钟化小时", "分钟化秒","秒化分钟","秒化小时","小时化秒", };
     /** 计算器上键的按钮 */
     private JButton keys[] = new JButton[KEYS.length];
     /** 计算器上的功能键的按钮 */
     private JButton commands[] = new JButton[COMMAND.length];
     /** 计算器左边的M的按钮 */
     private JButton m[] = new JButton[M.length];
     /** 计算结果文本框 */
     private JTextField resultText = new JTextField("0");
 
     // 标志用户按的是否是整个表达式的第一个数字,或者是运算符后的第一个数字
     private boolean firstDigit = true;
     // 计算的中间结果。
     private double resultNum = 0.0;
     // 当前运算的运算符
     private String operator = "=";
     // 操作是否合法
     private boolean operateValidFlag = true;
 
 StringBuffer sb = new StringBuffer();  // 存储输入的数字
 String vl = null;  // 存储事件点击的字符

 

   //标准型计算器
 public Calculator_Time() {
  setTitle("标准型");  
         // 初始化计算器 super p114
      
         // 设置计算器的背景颜色
         this.setBackground(Color.LIGHT_GRAY);
         this.setTitle("计算器");
         // 在屏幕(500, 300)坐标处显示计算器
         this.setLocation(500, 300);
         // 不许修改计算器的大小
         this.setSize(600, 400);
         this.setResizable(false);
         // 使计算器中各组件大小合适
         //使这个外部容器自动调整成刚好装下这几个按钮的大小的尺寸。
    

  JMenuBar menuBar = new JMenuBar();
  setJMenuBar(menuBar);

  JMenu menu = new JMenu("功能");
  menuBar.add(menu);
  

  JMenuItem menuItem = new JMenuItem("标准型");
  menu.add(menuItem);
  menuItem.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent e) {
    Calculate_Ordinary ordinary = new Calculate_Ordinary();
    ordinary.setVisible(true);
   }
  });

  JMenuItem menuItem_1 = new JMenuItem("科学型");
  
  menuItem_1.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent arg0) {
    Calculator_Science science = new Calculator_Science();
    science.setVisible(true);
   }
  });
  menu.add(menuItem_1);
  JMenuItem menuItem_2 = new JMenuItem("时间换算");
  menu.add(menuItem_2);
      
  JMenu menu_1 = new JMenu("关于");
  menuBar.add(menu_1);
  JMenuItem menuItem_4 = new JMenuItem("使用帮助");
  menu_1.add(menuItem_4);
  
  JMenuItem menuItem_5 = new JMenuItem("关于作者");
  menu_1.add(menuItem_5);
  menuItem_5.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent arg0) {
    Calculator_Author calculator_Author = new Calculator_Author();
    calculator_Author.setVisible(true);
   }
  });
   resultText.setHorizontalAlignment(JTextField.RIGHT);
        
         // 设置文本框背景颜色为白色
         resultText.setBackground(Color.white);
         resultText.setFont(new Font("TimesRoman",Font.BOLD,46));
        
 
         // 初始化计算器上键的按钮，将键放在一个画板内
         JPanel calckeysPanel = new JPanel();    
         calckeysPanel.setLayout(new GridLayout(4, 3, 3, 3));
         for (int i = 0; i < KEYS.length; i++) {
             keys[i] = new JButton(KEYS[i]);
             calckeysPanel.add(keys[i]);
             keys[i].setForeground(Color.white);
             keys[i].setBackground(Color.DARK_GRAY);
             keys[i].setFont(new Font("Courir",Font.PLAIN,20));
         }
        
          
        
         // 运算符键用红色标示，其他键用黑色表示
        
       
         // 初始化功能键，都用红色标示。将功能键放在一个画板内
         JPanel commandsPanel = new JPanel();
         // 用网格布局器，1行，3列的网格，网格之间的水平方向间隔为3个象素，垂直方向间隔为3个象素
         commandsPanel.setLayout(new GridLayout(1, 3, 3, 3));
         for (int i = 0; i < COMMAND.length; i++) {
             commands[i] = new JButton(COMMAND[i]);
             commandsPanel.add(commands[i]);
             commands[i].setBackground(Color.white);
             commands[i].setForeground(Color.DARK_GRAY);
             commands[i].setFont(new Font("Courir",Font.PLAIN,20));
            
         }
 
         // 初始化M键，用红色标示，将M键放在一个画板内
         JPanel calmsPanel = new JPanel();
         // 用网格布局管理器，5行，1列的网格，网格之间的水平方向间隔为3个象素，垂直方向间隔为3个象素
         calmsPanel.setLayout(new GridLayout(3, 2, 3, 3));
         for (int i = 0; i < M.length; i++) {
             m[i] = new JButton(M[i]);
             m[i].setBackground(Color.white);
             calmsPanel.add(m[i]);                         
         }
 
         // 下面进行计算器的整体布局，将calckeys和command画板放在计算器的中部，
         // 将文本框放在北部，将calms画板放在计算器的西部。
 
         // 新建一个大的画板，将上面建立的command和calckeys画板放在该画板内
         JPanel panel1 = new JPanel();
         // 画板采用边界布局管理器，画板里组件之间的水平和垂直方向上间隔都为3象素
         panel1.setLayout(new BorderLayout(3, 3));
         panel1.add("North", commandsPanel);
         panel1.add("Center", calckeysPanel);
         panel1.add("East",calmsPanel);
 
         // 建立一个画板放文本框
         JPanel top = new JPanel();
         top.setLayout(new BorderLayout());
         top.add("Center", resultText);
        
 
         // 整体布局
         getContentPane().setLayout(new BorderLayout(3, 5));
         getContentPane().add("North", top);
         getContentPane().add("Center", panel1);
       
         // 为各按钮添加事件侦听器
         // 都使用同一个事件侦听器，即本对象。本类的声明中有implements ActionListener
         for (int i = 0; i < KEYS.length; i++) {
             keys[i].addActionListener(this);
         }
         for (int i = 0; i < COMMAND.length; i++) {
             commands[i].addActionListener(this);
         }
         for (int i = 0; i < M.length; i++) {
             m[i].addActionListener(this);
            
         }
    
     }
 
 
 //添加事件点击
 public void actionPerformed(ActionEvent e) {
        // 获取事件源的标签
        String label = e.getActionCommand();
        if (label.equals(COMMAND[0])) {
            // 用户按了"Backspace"键
            handleBackspace();
        } else if (label.equals(COMMAND[1])) {
            // 用户按了"CE"键
            resultText.setText("0");
        } else if (label.equals(COMMAND[2])) {
            // 用户按了"C"键
            handleC();
        } else if ("0123456789.".indexOf(label) >= 0) {
            // 用户按了数字键或者小数点键
            handleNumber(label);
            // handlezero(zero);
        } else {
            // 用户按了运算符键
            handleOperator(label);
        }
    }
 
    /**
     * 处理Backspace键被按下的事件
     */
    private void handleBackspace() {
        String text = resultText.getText();
        int i = text.length();
        if (i > 0) {
            // 退格，将文本最后一个字符去掉
            text = text.substring(0, i - 1);
            if (text.length() == 0) {
                // 如果文本没有了内容，则初始化计算器的各种值
                resultText.setText("0");
                firstDigit = true;
                operator = "=";
            } else {
                // 显示新的文本
                resultText.setText(text);
            }
        }
    }
 
    /**
     * 处理数字键被按下的事件
     *
     * @param key
     */
    private void handleNumber(String key) {
        if (firstDigit) {
            // 输入的第一个数字
            resultText.setText(key);
        } else if ((key.equals(".")) && (resultText.getText().indexOf(".") < 0)) {
            // 输入的是小数点，并且之前没有小数点，则将小数点附在结果文本框的后面
            resultText.setText(resultText.getText() + ".");
        } else if (!key.equals(".")) {
            // 如果输入的不是小数点，则将数字附在结果文本框的后面
            resultText.setText(resultText.getText() + key);
        }
        // 以后输入的肯定不是第一个数字了
        firstDigit = false;
    }
 
    /**
     * 处理C键被按下的事件
     */
    private void handleC() {
        // 初始化计算器的各种值
        resultText.setText("0");
        firstDigit = true;
        operator = "=";
    }
 
    /**
     * 处理运算符键被按下的事件
     *
     * @param key
     */
    private void handleOperator(String key) {
        if (operator.equals("小时化分钟")) {
         
            // 除法运算
            // 如果当前结果文本框中的值等于0
            if (getNumberFromText() == 0.0) {
                // 操作不合法
                operateValidFlag = false;
                resultText.setText("除数不能为零");
            } else {
                resultNum =60* getNumberFromText();
            }
        } else if (operator.equals("秒化分钟")) {
            // 倒数运算
            if (resultNum == 0.0) {
                // 操作不合法
                operateValidFlag = false;
                resultText.setText("零没有倒数");
            } else {
                resultNum = resultNum/60;
            }
        } else if (operator.equals("+")) {
            // 加法运算
            resultNum = 60*getNumberFromText();
        } else if (operator.equals("秒化小时")) {
            // 减法运算
            resultNum = getNumberFromText()/3600;
        } else if (operator.equals("分钟化小时")) {
            // 乘法运算
            resultNum = getNumberFromText()/60;
        } else if (operator.equals("小时化秒")) {
            // 平方根运算
            resultNum =3600*getNumberFromText() ;
        } else if (operator.equals("分钟化秒")) {
            // 百分号运算，除以100
            resultNum = resultNum *60;
        } else if (operator.equals("+/-")) {
            // 正数负数运算
            resultNum = resultNum * (-1);
        } else if (operator.equals("=")) {
            // 赋值运算
            resultNum = getNumberFromText();
        }
        if (operateValidFlag) {
            // 双精度浮点数的运算
            long t1;
            double t2;
            t1 = (long) resultNum;
            t2 = resultNum - t1;
            if (t2 == 0) {
                resultText.setText(String.valueOf(t1));
            } else {
                resultText.setText(String.valueOf(resultNum));
            }
        }
        // 运算符等于用户按的按钮
        operator = key;
        firstDigit = true;
        operateValidFlag = true;
    }
 
    /**
     * 从结果文本框中获取数字
     *
     * @return
     */
    private double getNumberFromText() {
        double result = 0;
        try {
            result = Double.valueOf(resultText.getText()).doubleValue();
        } catch (NumberFormatException e) {
        }
        return result;
    }
 
    public static void main(String args[]) {
        Calculator_Time calculator1 = new Calculator_Time();
        calculator1.setVisible(true);
        calculator1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

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//科学计算器

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Stack;

import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JTextArea;
import javax.swing.JRadioButton;
import javax.swing.JButton;
import java.awt.Color;
import java.awt.Font;

public class Calculator_Science extends JFrame implements ActionListener {

 private JPanel contentPane;
 private JTextArea textArea;
 StringBuffer sb = new StringBuffer(); // 存储输入的数字
 String vl = null; // 存储事件点击的字符

 public Calculator_Science() {
  setTitle("科学型");
  setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  setBounds(100, 100, 515, 442);

  JMenuBar menuBar = new JMenuBar();
  setJMenuBar(menuBar);

  JMenu menu = new JMenu("功能");
  menuBar.add(menu);

  JMenuItem menuItem = new JMenuItem("标准型");
  menuItem.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent e) {
    Calculate_Ordinary ordinary = new Calculate_Ordinary();
    ordinary.setVisible(true);
   }
  });
  menu.add(menuItem);

  JMenuItem menuItem_1 = new JMenuItem("科学型");
  menu.add(menuItem_1);
        JMenuItem menuItem_2 = new JMenuItem("时间换算");
        menu.add(menuItem_2);
  
  menuItem_2.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent arg0) {
    Calculator_Time time = new Calculator_Time();
    time.setVisible(true);
   }
  });  

  JMenu menu_1 = new JMenu("关于");
  menuBar.add(menu_1);

  JMenuItem menuItem_4 = new JMenuItem("使用帮助");
  menu_1.add(menuItem_4);

  JMenuItem menuItem_5 = new JMenuItem("关于作者");
  menu_1.add(menuItem_4);
  menuItem_5.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent e) {
    Calculator_Author calculator_Author = new Calculator_Author();
    calculator_Author.setVisible(true);
   }
  });
  menu_1.add(menuItem_5);
  contentPane = new JPanel();
  contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));//
  setContentPane(contentPane);
  contentPane.setLayout(null);

  textArea = new JTextArea();
  textArea.setLineWrap(true);
  textArea.setFont(new Font("微软雅黑", Font.PLAIN, 20));
  textArea.setBackground(new Color(255, 250, 240));
  textArea.setText("0");
  textArea.setBounds(10, 0, 479, 81);
  contentPane.add(textArea);

  ButtonGroup bg = new ButtonGroup();
  JRadioButton radioButton = new JRadioButton("度", true);
  radioButton.setBounds(6, 87, 67, 40);
  contentPane.add(radioButton);

  JRadioButton radioButton_1 = new JRadioButton("弧度");
  radioButton_1.setBounds(91, 87, 67, 40);
  contentPane.add(radioButton_1);

  JRadioButton radioButton_2 = new JRadioButton("梯度");
  radioButton_2.setBounds(189, 87, 60, 40);
  contentPane.add(radioButton_2);
  bg.add(radioButton);
  bg.add(radioButton_1);
  bg.add(radioButton_2);

  JButton btnNewButton = new JButton("");
  btnNewButton.setBorder(null);
  btnNewButton.setBounds(10, 132, 40, 40);
  contentPane.add(btnNewButton);
  btnNewButton.addActionListener(this);

  JButton btnLnv = new JButton("lg");
  btnLnv.setBorder(null);
  btnLnv.setBounds(60, 132, 40, 40);
  contentPane.add(btnLnv);
  btnLnv.addActionListener(this);

  JButton btnLn = new JButton("ln");
  btnLn.setBorder(null);
  btnLn.setBounds(105, 132, 40, 40);
  contentPane.add(btnLn);
  btnLn.addActionListener(this);

  JButton button_1 = new JButton("(");
  button_1.setBorder(null);
  button_1.setBounds(155, 132, 40, 40);
  contentPane.add(button_1);
  button_1.addActionListener(this);

  JButton button_2 = new JButton(")");
  button_2.setBorder(null);
  button_2.setBounds(209, 132, 40, 40);
  contentPane.add(button_2);
  button_2.addActionListener(this);

  JButton btnInt = new JButton("int");
  btnInt.setBorder(null);
  btnInt.setBounds(10, 182, 40, 40);
  contentPane.add(btnInt);
  btnInt.addActionListener(this);

  JButton btnSinh = new JButton("sinh");
  btnSinh.setBorder(null);
  btnSinh.setBounds(60, 182, 40, 40);
  contentPane.add(btnSinh);
  btnSinh.addActionListener(this);

  JButton btnSin = new JButton("sin");
  btnSin.setBorder(null);
  btnSin.setBounds(105, 182, 40, 40);
  contentPane.add(btnSin);
  btnSin.addActionListener(this);

  JButton btnX = new JButton("x2");
  btnX.setBorder(null);
  btnX.setBounds(155, 182, 40, 40);
  contentPane.add(btnX);
  btnX.addActionListener(this);

  JButton btnN = new JButton("n!");
  btnN.setBorder(null);
  btnN.setBounds(209, 182, 40, 40);
  contentPane.add(btnN);
  btnN.addActionListener(this);

  JButton btnDms = new JButton("dms");
  btnDms.setBorder(null);
  btnDms.setBounds(10, 232, 40, 40);
  contentPane.add(btnDms);
  btnDms.addActionListener(this);

  JButton btnCosh = new JButton("cosh");
  btnCosh.setBorder(null);
  btnCosh.setBounds(60, 232, 40, 40);
  contentPane.add(btnCosh);
  btnCosh.addActionListener(this);

  JButton btnCos = new JButton("cos");
  btnCos.setBorder(null);
  btnCos.setBounds(105, 232, 40, 40);
  contentPane.add(btnCos);
  btnCos.addActionListener(this);

  JButton btnXy = new JButton("x^y");
  btnXy.setBorder(null);
  btnXy.setBounds(155, 232, 40, 40);
  contentPane.add(btnXy);
  btnXy.addActionListener(this);

  JButton btnYx = new JButton("y√x");
  btnYx.setBorder(null);
  btnYx.setBounds(209, 232, 40, 40);
  contentPane.add(btnYx);
  btnYx.addActionListener(this);

  JButton button_13 = new JButton("π");
  button_13.setBorder(null);
  button_13.setBounds(10, 282, 40, 40);
  contentPane.add(button_13);
  button_13.addActionListener(this);

  JButton btnTanh = new JButton("tanh");
  btnTanh.setBorder(null);
  btnTanh.setBounds(60, 282, 40, 40);
  contentPane.add(btnTanh);
  btnTanh.addActionListener(this);

  JButton btnTan = new JButton("tan");
  btnTan.setBorder(null);
  btnTan.setBounds(105, 282, 40, 40);
  contentPane.add(btnTan);
  btnTan.addActionListener(this);

  JButton btnX_1 = new JButton("x^3");
  btnX_1.setBorder(null);
  btnX_1.setBounds(155, 282, 40, 40);
  contentPane.add(btnX_1);
  btnX_1.addActionListener(this);

  JButton btnx = new JButton("3√x");
  btnx.setBorder(null);
  btnx.setBounds(209, 282, 40, 40);
  contentPane.add(btnx);
  btnx.addActionListener(this);

  JButton btnFe = new JButton("F-E");
  btnFe.setBorder(null);
  btnFe.setBounds(10, 332, 40, 40);
  contentPane.add(btnFe);
  btnFe.addActionListener(this);

  JButton btnExp = new JButton("Exp");
  btnExp.setBorder(null);
  btnExp.setBounds(60, 332, 40, 40);
  contentPane.add(btnExp);
  btnExp.addActionListener(this);

  JButton btnMod = new JButton("Mod");
  btnMod.setBorder(null);
  btnMod.setBounds(105, 332, 40, 40);
  contentPane.add(btnMod);
  btnMod.addActionListener(this);

  JButton btnLog = new JButton("log");
  btnLog.setBorder(null);
  btnLog.setBounds(155, 332, 40, 40);
  contentPane.add(btnLog);
  btnLog.addActionListener(this);

  JButton btnx_1 = new JButton("10^x");
  btnx_1.setBorder(null);
  btnx_1.setBounds(209, 332, 40, 40);
  contentPane.add(btnx_1);
  btnx_1.addActionListener(this);

  JButton button_23 = new JButton("←");
  button_23.setBorder(null);
  button_23.setBounds(259, 132, 40, 40);
  contentPane.add(button_23);
  button_23.addActionListener(this);

  JButton btnCe = new JButton("CE");
  btnCe.setBorder(null);
  btnCe.setBounds(309, 132, 40, 40);
  contentPane.add(btnCe);
  btnCe.addActionListener(this);

  JButton btnC = new JButton("C");
  btnC.setBorder(null);
  btnC.setBounds(354, 132, 40, 40);
  contentPane.add(btnC);
  btnC.addActionListener(this);

  JButton button_26 = new JButton("±");
  button_26.setBorder(null);
  button_26.setBounds(404, 132, 40, 40);
  contentPane.add(button_26);
  button_26.addActionListener(this);

  JButton button_27 = new JButton("√");
  button_27.setBorder(null);
  button_27.setBounds(458, 132, 40, 40);
  contentPane.add(button_27);
  button_27.addActionListener(this);

  JButton btnMc = new JButton("MC");
  btnMc.setBorder(null);
  btnMc.setBounds(259, 87, 40, 40);
  contentPane.add(btnMc);
  btnMc.addActionListener(this);

  JButton btnMr = new JButton("MR");
  btnMr.setBorder(null);
  btnMr.setBounds(309, 87, 40, 40);
  contentPane.add(btnMr);
  btnMr.addActionListener(this);

  JButton btnMs = new JButton("MS");
  btnMs.setBorder(null);
  btnMs.setBounds(354, 87, 40, 40);
  contentPane.add(btnMs);
  btnMs.addActionListener(this);

  JButton btnM = new JButton("M+");
  btnM.setBorder(null);
  btnM.setBounds(404, 87, 40, 40);
  contentPane.add(btnM);
  btnM.addActionListener(this);

  JButton btnM_1 = new JButton("M-");
  btnM_1.setBorder(null);
  btnM_1.setBounds(458, 87, 40, 40);
  contentPane.add(btnM_1);
  btnM_1.addActionListener(this);

  JButton button_33 = new JButton("7");
  button_33.setBorder(null);
  button_33.setBounds(259, 182, 40, 40);
  contentPane.add(button_33);
  button_33.addActionListener(this);

  JButton button_34 = new JButton("8");
  button_34.setBorder(null);
  button_34.setBounds(309, 182, 40, 40);
  contentPane.add(button_34);
  button_34.addActionListener(this);

  JButton button_35 = new JButton("9");
  button_35.setBorder(null);
  button_35.setBounds(354, 182, 40, 40);
  contentPane.add(button_35);
  button_35.addActionListener(this);
  JButton button_36 = new JButton("/");
  button_36.setBorder(null);
  button_36.setBounds(404, 182, 40, 40);
  contentPane.add(button_36);
  button_36.addActionListener(this);

  JButton button_37 = new JButton("%");
  button_37.setBorder(null);
  button_37.setBounds(458, 182, 40, 40);
  contentPane.add(button_37);
  button_37.addActionListener(this);

  JButton button_38 = new JButton("4");
  button_38.setBorder(null);
  button_38.setBounds(259, 232, 40, 40);
  contentPane.add(button_38);
  button_38.addActionListener(this);

  JButton button_39 = new JButton("5");
  button_39.setBorder(null);
  button_39.setBounds(309, 232, 40, 40);
  contentPane.add(button_39);
  button_39.addActionListener(this);

  JButton button_40 = new JButton("6");
  button_40.setBorder(null);
  button_40.setBounds(354, 232, 40, 40);
  contentPane.add(button_40);
  button_40.addActionListener(this);

  JButton button_41 = new JButton("*");
  button_41.setBorder(null);
  button_41.setBounds(404, 232, 40, 40);
  contentPane.add(button_41);
  button_41.addActionListener(this);

  JButton button_42 = new JButton("1/x");
  button_42.setBorder(null);
  button_42.setBounds(458, 232, 40, 40);
  contentPane.add(button_42);
  button_42.addActionListener(this);

  JButton button_43 = new JButton("1");
  button_43.setBorder(null);
  button_43.setBounds(259, 282, 40, 40);
  contentPane.add(button_43);
  button_43.addActionListener(this);

  JButton button_44 = new JButton("2");
  button_44.setBorder(null);
  button_44.setBounds(309, 282, 40, 40);
  contentPane.add(button_44);
  button_44.addActionListener(this);

  JButton button_45 = new JButton("3");
  button_45.setBorder(null);
  button_45.setBounds(354, 282, 40, 40);
  contentPane.add(button_45);
  button_45.addActionListener(this);

  JButton button_46 = new JButton("-");
  button_46.setBorder(null);
  button_46.setBounds(404, 282, 40, 40);
  contentPane.add(button_46);
  button_46.addActionListener(this);

  JButton button_50 = new JButton(".");
  button_50.setBorder(null);
  button_50.setBounds(354, 332, 40, 40);
  contentPane.add(button_50);
  button_50.addActionListener(this);

  JButton button_51 = new JButton("+");
  button_51.setBorder(null);
  button_51.setBounds(404, 332, 40, 40);
  contentPane.add(button_51);
  button_51.addActionListener(this);

  JButton btnNewButton_1 = new JButton("=");
  btnNewButton_1.setBorder(null);
  btnNewButton_1.setBounds(458, 282, 40, 90);
  contentPane.add(btnNewButton_1);
  btnNewButton_1.addActionListener(this);

  JButton btnNewButton_2 = new JButton("0");
  btnNewButton_2.setBounds(259, 332, 90, 40);
  contentPane.add(btnNewButton_2);
  btnNewButton_2.addActionListener(this);

 }

 //添加事件点击
 public void actionPerformed(ActionEvent e) {
  vl = e.getActionCommand();

   try {
    if(vl.equals(".") || Integer.parseInt(vl) % 2 == 1 || Integer.parseInt(vl) % 2 == 0) {
     sb.append(vl);
    }
   } catch (Exception c) {
    if(vl.equals("+") || vl.equals("-")
      || vl.equals("*") || vl.equals("/") ||vl.equals("log") ||
      vl.equals("√") || vl.equals("%") ||vl.equals("n!") ||
      vl.equals("int") || vl.equals("sinh") ||vl.equals("lg") ||
      vl.equals("sin") || vl.equals("x2") ||vl.equals("ln") ||
      vl.equals("cosh") || vl.equals("cos") || vl.equals("(") ||
      vl.equals("x^y") || vl.equals("y√x") || vl.equals(")") ||
      vl.equals("tanh")  || vl.equals("tan") ||  vl.equals("π") ||
      vl.equals("x^3") || vl.equals("3√x") ||
      vl.equals("Mod") || vl.equals("10^x") || vl.equals("1/x")) {
     sb.append(" "+vl+" ");
    }else if(vl.equals("=")) {
     sb.append(" "+"="+" "+ Algorithm(sb));
    }else if(vl.equals("C")) {
     sb.delete(0, sb.length());
    }else if(vl.equals("C")) {
     sb.delete(sb.length()-3, sb.length());
    }else if(vl.equals("←")) {
     sb.delete(sb.length()-1, sb.length());
    }
   }
   
   textArea.setText(sb.toString());
 }

 //运算的方法
 private String Algorithm(StringBuffer str) {
  String a = str.toString();
  String n[];
  n = a.split(" ");
  double ans = 0d;
  
  for(int i = 1; i < n.length; i++) {
   if(n[i].equals("+")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i - 1]);
    ans = after+Front;
   }
   
   if(n[i].equals("-")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i - 1]);
    ans = Front-after;
   }
   
   if(n[i].equals("*")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i - 1]);
    ans = after*Front;
   }
   
   if(n[i].equals("/")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i - 1]);
    ans = Front/after;
   }
   
   if(n[i].equals("√")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.sqrt(after);
   }
   
   if(n[i].equals("%")) {
    double Front = Double.parseDouble(n[i - 1]);
    ans = Front/100;
   }
   
   if(n[i].equals("int")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.ceil(after);
   }
   
   if(n[i].equals("sinh")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.sinh(after);
   }
   
   if(n[i].equals("sinh")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.sin(after);
   }
   
   if(n[i].equals("lg")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.log10(after);
   }
   
   if(n[i].equals("x2")) {
    double Front = Double.parseDouble(n[i - 1]);
    ans = Front*Front;
   }
   
   
   
   if(n[i].equals("cosh")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.cosh(after);
   }
   
   if(n[i].equals("cos")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.cos(after);
   }
   
   if(n[i].equals("x^y")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i - 1]);
    ans = Math.pow(Front, after);
   }
   
   if(n[i].equals("y√x")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i - 1]);
    ans = Math.pow(Front, 1d/after);
   }
   
   if(n[i].equals("tanh")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.tanh(after);
   }
   
   if(n[i].equals("tan")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.tan(after);
   }
   
   if(n[i].equals("x^3")) {
    double Front = Double.parseDouble(n[i - 1]);
    ans = Front*Front*Front;
   }
   
   if(n[i].equals("3√x")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.pow(after, 1d/3);
   }
   
   if(n[i].equals("Mod")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i - 1]);
    ans = (Front%after);
   }
   
   if(n[i].equals("ln")) {
    double after = Double.parseDouble(n[i + 1]);
   
    ans =Math.log(after);
   }
   
   if(n[i].equals("10^x")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = Math.pow(10, after);
   }
   
   if(n[i].equals("1/x")) {
    double after = Double.parseDouble(n[i + 1]);
    ans = 1/after;
   }
   if(n[i].equals("π")) {
    double after = Double.parseDouble(n[i - 1]);
    ans = 3.14*after;
   }if(n[i].equals("log")) {
    double after = Double.parseDouble(n[i + 1]);
    double Front = Double.parseDouble(n[i -1 ]);
    ans = Math.log(after)/Math.log(Front);
   }
   
   if(n[i].equals("n!")) {
    double after = Double.parseDouble(n[i - 1]);
    int e ;
    int c=1;
    for(e=1;e<=after;e++)
    {c=c*e;
    ans=c;}
    
    
    
   }
   
   
  }
  
  String result = String.valueOf(ans);
  return result;

 }
 
 public static void main(String[] args) {
  EventQueue.invokeLater(new Runnable() {
   public void run() {
    try {
     Calculator_Science frame = new Calculator_Science();
     frame.setVisible(true);
     frame.setResizable(false);
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  });
 }
}

------------------------------------------------------------------------------

//标准计算器

import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JTextArea;
import javax.swing.JTextField;

import java.awt.Color;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import java.util.Stack;
import java.awt.event.ActionEvent;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;

import java.awt.Font;
import java.awt.GridLayout;

public class Calculate_Ordinary extends JFrame implements ActionListener {

  private final String[] KEYS = { "7", "8", "9", "/", "√", "4", "5", "6",
             "*", "%", "1", "2", "3", "-", "1/x", "0", "+/-", ".", "+", "=" };
     /** 计算器上的功能键的显示名字      final p86*/
     private final String[] COMMAND = { "Backspace", "CE", "C" };
     /** 计算器左边的M的显示名字 */
     private final String[] M = {"MC", "MR", "MS", "M+" };
     /** 计算器上键的按钮 */
     private JButton keys[] = new JButton[KEYS.length];
     /** 计算器上的功能键的按钮 */
     private JButton commands[] = new JButton[COMMAND.length];
     /** 计算器左边的M的按钮 */
     private JButton m[] = new JButton[M.length];
     /** 计算结果文本框 */
     private JTextField resultText = new JTextField("0");
 
     // 标志用户按的是否是整个表达式的第一个数字,或者是运算符后的第一个数字
     private boolean firstDigit = true;
     // 计算的中间结果。
     private double resultNum = 0.0;
     // 当前运算的运算符
     private String operator = "=";
     // 操作是否合法
     private boolean operateValidFlag = true;
 
 StringBuffer sb = new StringBuffer();  // 存储输入的数字
 String vl = null;  // 存储事件点击的字符

 

   //标准型计算器
 public Calculate_Ordinary() {
  setTitle("标准型");  
         // 初始化计算器 super p114
      
         // 设置计算器的背景颜色
         this.setBackground(Color.LIGHT_GRAY);
         this.setTitle("标准计算器");
         // 在屏幕(500, 300)坐标处显示计算器
         this.setLocation(500, 300);
         // 不许修改计算器的大小
         this.setSize(500, 500);
         this.setResizable(false);
         // 使计算器中各组件大小合适
         //使这个外部容器自动调整成刚好装下这几个按钮的大小的尺寸。
    

  JMenuBar menuBar = new JMenuBar();
  setJMenuBar(menuBar);

  JMenu menu = new JMenu("功能");
  menuBar.add(menu);
  

  JMenuItem menuItem = new JMenuItem("标准型");
  menu.add(menuItem);

  JMenuItem menuItem_1 = new JMenuItem("科学型");
  menu.add(menuItem_1);
  menuItem_1.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent arg0) {
    Calculator_Science science = new Calculator_Science();
    science.setVisible(true);
   }
  });
         JMenuItem menuItem_2 = new JMenuItem("时间换算");
         menu.add(menuItem_2);
  menuItem_2.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent arg0) {
    Calculator_Time time = new Calculator_Time();
    time.setVisible(true);
   }
  }); 
  
  JMenu menu_1 = new JMenu("关于");
  menuBar.add(menu_1);
  
  JMenuItem menuItem_4 = new JMenuItem("使用帮助");
  menu_1.add(menuItem_4);
  
  JMenuItem menuItem_5 = new JMenuItem("关于作者");
  menu_1.add(menuItem_5);
  menuItem_5.addActionListener(new ActionListener() {
   public void actionPerformed(ActionEvent arg0) {
    Calculator_Author calculator_Author = new Calculator_Author();
    calculator_Author.setVisible(true);
   }
  });
   resultText.setHorizontalAlignment(JTextField.RIGHT);
        
         // 设置文本框背景颜色为白色
         resultText.setBackground(Color.white);
         resultText.setFont(new Font("TimesRoman",Font.BOLD,46));
        
 
         // 初始化计算器上键的按钮，将键放在一个画板内
         JPanel calckeysPanel = new JPanel();
         // 用网格布局器，4行，5列的网格，网格之间的水平方向间隔为3个象素，垂直方向间隔为3个象素
         calckeysPanel.setLayout(new GridLayout(4, 5, 3, 3));
         for (int i = 0; i < KEYS.length; i++) {
             keys[i] = new JButton(KEYS[i]);
             calckeysPanel.add(keys[i]);
             keys[i].setForeground(Color.white);
             keys[i].setBackground(Color.DARK_GRAY);
             keys[i].setFont(new Font("Courir",Font.ITALIC,20));
         }
        
          
        
         // 运算符键用红色标示，其他键用黑色表示
         keys[3].setForeground(Color.white);
         keys[8].setForeground(Color.white);
         keys[13].setForeground(Color.white);
         keys[18].setForeground(Color.white);
         keys[19].setForeground(Color.white);
         keys[3].setBackground(Color.getHSBColor(250, 155, 140));
         keys[8].setBackground(Color.getHSBColor(250, 155, 140));
         keys[13].setBackground(Color.getHSBColor(250, 155, 140));
         keys[18].setBackground(Color.getHSBColor(250, 155, 140));
         keys[19].setBackground(Color.getHSBColor(250, 155, 140));              
         // 初始化功能键，都用红色标示。将功能键放在一个画板内
         JPanel commandsPanel = new JPanel();
         // 用网格布局器，1行，3列的网格，网格之间的水平方向间隔为3个象素，垂直方向间隔为3个象素
         commandsPanel.setLayout(new GridLayout(1, 3, 3, 3));
         for (int i = 0; i < COMMAND.length; i++) {
             commands[i] = new JButton(COMMAND[i]);
             commandsPanel.add(commands[i]);
             commands[i].setForeground(Color.DARK_GRAY);
             commands[i].setFont(new Font("Courir",Font.PLAIN,20));
            
         }
 
         // 初始化M键，用红色标示，将M键放在一个画板内
         JPanel calmsPanel = new JPanel();
         // 用网格布局管理器，5行，1列的网格，网格之间的水平方向间隔为3个象素，垂直方向间隔为3个象素
         calmsPanel.setLayout(new GridLayout(4, 1, 3, 3));
         for (int i = 0; i < M.length; i++) {
             m[i] = new JButton(M[i]);
             calmsPanel.add(m[i]);
             m[i].setForeground(Color.red);
             m[i].setFont(new Font("Courir",Font.PLAIN,20));
            
         }
 
         // 下面进行计算器的整体布局，将calckeys和command画板放在计算器的中部，
         // 将文本框放在北部，将calms画板放在计算器的西部。
 
         // 新建一个大的画板，将上面建立的command和calckeys画板放在该画板内
         JPanel panel1 = new JPanel();
         // 画板采用边界布局管理器，画板里组件之间的水平和垂直方向上间隔都为3象素
         panel1.setLayout(new BorderLayout(3, 3));
         panel1.add("North", commandsPanel);
         panel1.add("Center", calckeysPanel);
 
         // 建立一个画板放文本框
         JPanel top = new JPanel();
         top.setLayout(new BorderLayout());
         top.add("Center", resultText);
        
 
         // 整体布局
         getContentPane().setLayout(new BorderLayout(3, 5));
         getContentPane().add("North", top);
         getContentPane().add("Center", panel1);
         getContentPane().add("West", calmsPanel);
         // 为各按钮添加事件侦听器
         // 都使用同一个事件侦听器，即本对象。本类的声明中有implements ActionListener
         for (int i = 0; i < KEYS.length; i++) {
             keys[i].addActionListener(this);
         }
         for (int i = 0; i < COMMAND.length; i++) {
             commands[i].addActionListener(this);
         }
         for (int i = 0; i < M.length; i++) {
             m[i].addActionListener(this);
            
         }
    
     }
 
 
 //添加事件点击
 public void actionPerformed(ActionEvent e) {
        // 获取事件源的标签
        String label = e.getActionCommand();
        if (label.equals(COMMAND[0])) {
            // 用户按了"Backspace"键
            handleBackspace();
        } else if (label.equals(COMMAND[1])) {
            // 用户按了"CE"键
            resultText.setText("0");
        } else if (label.equals(COMMAND[2])) {
            // 用户按了"C"键
            handleC();
        } else if ("0123456789.".indexOf(label) >= 0) {
            // 用户按了数字键或者小数点键
            handleNumber(label);
            // handlezero(zero);
        } else {
            // 用户按了运算符键
            handleOperator(label);
        }
    }
 
    /**
     * 处理Backspace键被按下的事件
     */
    private void handleBackspace() {
        String text = resultText.getText();
        int i = text.length();
        if (i > 0) {
            // 退格，将文本最后一个字符去掉
            text = text.substring(0, i - 1);
            if (text.length() == 0) {
                // 如果文本没有了内容，则初始化计算器的各种值
                resultText.setText("0");
                firstDigit = true;
                operator = "=";
            } else {
                // 显示新的文本
                resultText.setText(text);
            }
        }
    }
 
    /**
     * 处理数字键被按下的事件
     *
     * @param key
     */
    private void handleNumber(String key) {
        if (firstDigit) {
            // 输入的第一个数字
            resultText.setText(key);
        } else if ((key.equals(".")) && (resultText.getText().indexOf(".") < 0)) {
            // 输入的是小数点，并且之前没有小数点，则将小数点附在结果文本框的后面
            resultText.setText(resultText.getText() + ".");
        } else if (!key.equals(".")) {
            // 如果输入的不是小数点，则将数字附在结果文本框的后面
            resultText.setText(resultText.getText() + key);
        }
        // 以后输入的肯定不是第一个数字了
        firstDigit = false;
    }
 
    /**
     * 处理C键被按下的事件
     */
    private void handleC() {
        // 初始化计算器的各种值
        resultText.setText("0");
        firstDigit = true;
        operator = "=";
    }
 
    /**
     * 处理运算符键被按下的事件
     *
     * @param key
     */
    private void handleOperator(String key) {
        if (operator.equals("/")) {
         
            // 除法运算
            // 如果当前结果文本框中的值等于0
            if (getNumberFromText() == 0.0) {
                // 操作不合法
                operateValidFlag = false;
                resultText.setText("除数不能为零");
            } else {
                resultNum /= getNumberFromText();
            }
        } else if (operator.equals("1/x")) {
            // 倒数运算
            if (resultNum == 0.0) {
                // 操作不合法
                operateValidFlag = false;
                resultText.setText("零没有倒数");
            } else {
                resultNum = 1 / resultNum;
            }
        } else if (operator.equals("+")) {
            // 加法运算
            resultNum += getNumberFromText();
        } else if (operator.equals("-")) {
            // 减法运算
            resultNum -= getNumberFromText();
        } else if (operator.equals("*")) {
            // 乘法运算
            resultNum *= getNumberFromText();
        } else if (operator.equals("√")) {
            // 平方根运算
            resultNum = Math.sqrt(resultNum);
        } else if (operator.equals("%")) {
            // 百分号运算，除以100
            resultNum = resultNum / 100;
        } else if (operator.equals("+/-")) {
            // 正数负数运算
            resultNum = resultNum * (-1);
        } else if (operator.equals("=")) {
            // 赋值运算
            resultNum = getNumberFromText();
        }
        if (operateValidFlag) {
            // 双精度浮点数的运算
            long t1;
            double t2;
            t1 = (long) resultNum;
            t2 = resultNum - t1;
            if (t2 == 0) {
                resultText.setText(String.valueOf(t1));
            } else {
                resultText.setText(String.valueOf(resultNum));
            }
        }
        // 运算符等于用户按的按钮
        operator = key;
        firstDigit = true;
        operateValidFlag = true;
    }
 
    /**
     * 从结果文本框中获取数字
     *
     * @return
     */
    private double getNumberFromText() {
        double result = 0;
        try {
            result = Double.valueOf(resultText.getText()).doubleValue();
        } catch (NumberFormatException e) {
        }
        return result;
    }
 
    public static void main(String args[]) {
        Calculate_Ordinary calculator1 = new Calculate_Ordinary();
        calculator1.setVisible(true);
        calculator1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
}

--------------------------------------------------------------------------------

//关于

import java.awt.BorderLayout;

import java.awt.Color;
import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JLabel;
import java.awt.Font;

public class Calculator_Author extends JFrame {

 private JPanel contentPane;

 /**
  * Launch the application.
  */
 public static void main(String[] args) {
  EventQueue.invokeLater(new Runnable() {
   public void run() {
    try {
     Calculator_Author frame = new Calculator_Author();
     frame.setVisible(true);
    } catch (Exception e) {
     e.printStackTrace();
    }
   }
  });
 }
 

 /**
  * Create the frame.
  */
 public Calculator_Author() {
  setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  setBounds(100, 100, 489, 335);
  contentPane = new JPanel();
  contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
  setContentPane(contentPane);
  contentPane.setLayout(null);
  
  JLabel lblNewLabel = new JLabel("小组成员：");
  lblNewLabel.setFont(new Font("华文彩云", Font.BOLD, 15));
  lblNewLabel.setBounds(20, 223, 530, 52);
  lblNewLabel.setForeground(Color.black);
  contentPane.add(lblNewLabel);
  
  JLabel label = new JLabel("软件二班:第六组");
  label.setFont(new Font("华文彩云", Font.BOLD, 30 ));
  label.setForeground(Color.BLUE);
  label.setBounds(120, 70, 300, 75);
  contentPane.add(label);

  
  JLabel lblqq = new JLabel("指导教师：");
  lblqq.setFont(new Font("华文彩云", Font.BOLD, 20));
  lblqq.setBounds(150, 150, 307, 73);
  contentPane.add(lblqq);
  lblqq.setForeground(Color.BLUE);
  
 }
}