科学计算器程序Java代码MC：清除独立内存里的数字MR：读出独立内存数字MS：将显示数字保存到独立内存,并取代内存中原有数字M+：将显示数字向独立内存累加(独立内存是一个临时寄放数字的存储器,方便计算)CE：纠错键(CLEAR ERROR).输入数字有错,按它可以重新输入C：表示清零,将计算器恢复到开机状态功能举例：源程序如下：import java.awt.BorderLayout;import javax.swing.JRadioButtonMenuItem; import javax.swing.JTextField;public class Calucator extends JFrame { private JTextField tf;private JPanel panel1, panel2, panel3, panel4;private JMenuBar myBar;private JMenu menu1, menu2, menu3;private JMenuItem editItem1, editItem2, help1, help2, help3;private JRadioButtonMenuItem seeItem1, seeItem2;//单选框private JCheckBoxMenuItem seeItem3;//复选框private ButtonGroup bgb;private String back;private boolean IfResult = true, flag = false;private String oper = "=";private double result = 0;private Num numActionListener;private DecimalFormat df;public Calucator(){super("科学计算器");//设置标题栏df= new DecimalFormat("#.####");//保留四位小数this.setLayout(new BorderLayout(10, 5));panel1 = new JPanel(new GridLayout(1, 3, 10, 10));panel2 = new JPanel(new GridLayout(5, 6, 5, 5));//5行6列panel3 = new JPanel(new GridLayout(5, 1, 5, 5));panel4= new JPanel(new BorderLayout(5, 5));/***菜单栏*/myBar = new JMenuBar();menu1 = new JMenu("编辑(E)");menu2 = new JMenu("查看(V)");menu3 = new JMenu("帮助(H)");menu1.setFont(new Font("宋体", Font.PLAIN, 12));menu2.setFont(new Font("宋体", Font.PLAIN, 12));menu3.setFont(new Font("宋体", Font.PLAIN, 12));/***编辑栏*/editItem1= new JMenuItem("复制(C) Ctrl+C");editItem2= new JMenuItem("粘贴(P) Ctrl+V");editItem1.setFont(new Font("宋体",Font.PLAIN,12));editItem2.setFont(new Font("宋体",Font.PLAIN,12));/***查看栏*/seeItem1= new JRadioButtonMenuItem("科学型(T)");seeItem2= new JRadioButtonMenuItem("标准型(S)");seeItem3= new JCheckBoxMenuItem("数字分组(I)");seeItem1.setFont(new Font("宋体",Font.PLAIN,12));seeItem2.setFont(new Font("宋体",Font.PLAIN,12));seeItem3.setFont(new Font("宋体",Font.PLAIN,12));/***帮助栏*/help1 = new JMenuItem("帮助主题(H)");help2= new JMenuItem("关于计算器(A)");help1.setFont(new Font("宋体",Font.PLAIN,12));help2.setFont(new Font("宋体",Font.PLAIN,12));bgb = new ButtonGroup();//选项组menu1.add(editItem1);menu1.add(editItem2);menu2.add(seeItem1);menu2.add(seeItem2);menu2.addSeparator();//添加一条分割线menu2.add(seeItem3);menu3.add(help1);menu3.addSeparator();//添加一条分割线menu3.add(help2);myBar.add(menu1);myBar.add(menu2);myBar.add(menu3);this.setJMenuBar(myBar);numActionListener= new Num();//实现数字监听/***文本域，即为计算器的屏幕显示区域*/tf = new JTextField();tf.setEditable(false);//文本区域不可编辑tf.setBackground(Color.white);//文本区域的背景色tf.setHorizontalAlignment(JTextField.RIGH T);//文字右对齐tf.setText("0");tf.setBorder(BorderFactory.createLoweredB evelBorder());init();//对计算器进行初始化}/***初始化操作*添加按钮*/private void init(){addButton(panel1, "Backspace", newClear(), Color.red);addButton(panel1, "CE", new Clear(), Color.red);addButton(panel1, "C", new Clear(), Color.red);addButton(panel2, "1/x", new Signs(), Color.magenta);addButton(panel2, "log", new Signs(), Color.magenta);addButton(panel2, "7", numActionListener, Color.blue);addButton(panel2, "8", numActionListener, Color.blue);addButton(panel2, "9", numActionListener, Color.blue);addButton(panel2, "÷", new Signs(), Color.red);addButton(panel2, "n!", new Signs(), Color.magenta);addButton(panel2, "sqrt", new Signs(), Color.magenta);addButton(panel2, "4", numActionListener, Color.blue);addButton(panel2, "5", numActionListener, Color.blue);addButton(panel2, "6", numActionListener, Color.blue);addButton(panel2, "×", new Signs(), Color.red);addButton(panel2, "sin", new Signs(), Color.magenta);addButton(panel2, "x^2", new Signs(), Color.magenta);addButton(panel2, "1", numActionListener, Color.blue);addButton(panel2, "2", numActionListener, Color.blue);addButton(panel2, "3", numActionListener, Color.blue);addButton(panel2, "-", new Signs(), Color.red);addButton(panel2, "cos", new Signs(), Color.magenta);addButton(panel2, "x^3", new Signs(), Color.magenta);addButton(panel2, "0", numActionListener, Color.blue);addButton(panel2, "-/+", new Clear(), Color.blue);addButton(panel2, ".", new Dot(), Color.blue);addButton(panel2, "+", new Signs(), Color.red);addButton(panel2, "tan", new Signs(), Color.magenta);addButton(panel2, "%", new Signs(), Color.magenta);addButton(panel2, "π", numActionListener, Color.orange);addButton(panel2, "e", numActionListener, Color.orange);addButton(panel2, "′″", new Signs(), Color.orange);addButton(panel2, "=", new Signs(), Color.red);JButton btns = new JButton("计算器");btns.setBorder(BorderFactory.createLowere dBevelBorder());btns.setEnabled(false);//按钮不可操作btns.setPreferredSize(new Dimension(20, 20));panel3.add(btns);//加入按钮addButton(panel3, "MC", null, Color.red);addButton(panel3, "MR", null, Color.red);addButton(panel3, "MS", null, Color.red);addButton(panel3, "M+", null, Color.red);panel4.add(panel1,BorderLayout.NORTH);panel4.add(panel2,BorderLayout.CENTER);this.add(tf, BorderLayout.NORTH);this.add(panel3, BorderLayout.WEST);this.add(panel4);pack();this.setResizable(false);//窗口不可改变大小this.setLocation(300, 200);this.setDefaultCloseOperation(JFrame.EXIT _ON_CLOSE);}/***统一设置按钮的的使用方式*@param panel*@param name*@param action*@param color*/private void addButton(JPanel panel, String name, ActionListener action, Color color){JButton bt = new JButton(name);panel.add(bt);//在面板上增加按钮bt.setForeground(color);//设置前景（字体）颜色bt.addActionListener(action);//增加监听事件}/***计算器的基础操作（+-×÷）*@param x*/private void getResult (double x){if(oper == "+"){result += x;}else if(oper == "-"){result -= x;}else if(oper == "×"){result *= x;}else if(oper == "÷"){result /= x;}else if(oper == "="){result = x;}tf.setText(df.format(result));}/***运算符号的事件监听*/class Signs implements ActionListener{ public void actionPerformed(ActionEvent e) {/** 用ActionEvent对象的getActionCommand()方法* 取得与引发事件对象相关的字符串*/String str = e.getActionCommand();/* sqrt求平方根*/if(str.equals("sqrt")){double i = Double.parseDouble(tf.getText());if(i>=0){/** String.valueOf() 转换为字符串* df.format() 按要求保留四位小数* Math.sqrt() 求算数平方根*/tf.setText(String.valueOf(df.format(Math.sq rt(i))));}else{tf.setText("负数不能开平方根");}}/* log求常用对数*/else if(str.equals("log")){double i = Double.parseDouble(tf.getText());if(i>0){tf.setText(String.valueOf(df.format(Math.lo g(i))));}else{tf.setText("负数不能求对数");}}/* %求百分比*/else if(str.equals("%")){tf.setText(df.format(Double.parseDouble(tf. getText()) / 100));}/* 1/x求倒数*/else if(str.equals("1/x")){if(Double.parseDouble(tf.getText()) == 0){tf.setText("除数不能为零");}else{tf.setText(df.format(1 / Double.parseDouble(tf.getText())));}}/* sin求正弦函数*/else if(str.equals("sin")){double i = Double.parseDouble(tf.getText());tf.setText(String.valueOf(df.format(Math.si n(i))));}/* cos求余弦函数*/else if(str.equals("cos")){double i = Double.parseDouble(tf.getText());tf.setText(String.valueOf(df.format(Math.co s(i))));}/* tan求正切函数*/else if(str.equals("tan")){double i = Double.parseDouble(tf.getText());tf.setText(String.valueOf(df.format(Math.ta n(i))));}/* n!求阶乘*/else if(str.equals("n!")){double i = Double.parseDouble(tf.getText());if((i%2==0)||(i%2==1))//判断为整数放进行阶乘操作{int j = (int)i;//强制类型转换int result=1;for(int k=1;k<=j;k++)result *= k;tf.setText(String.valueOf(result));}else{tf.setText("无法进行阶乘");}}/* x^2求平方*/else if(str.equals("x^2")){double i = Double.parseDouble(tf.getText());tf.setText(String.valueOf(df.format(i*i)));}/* x^3求立方*/else if(str.equals("x^3")){double i =Double.parseDouble(tf.getText());tf.setText(String.valueOf(df.format(i*i*i)));}/* ′″角度转换*//***将角度值转换成弧度值，方便三角函数的计算*/else if(str.equals("′″")){double i = Double.parseDouble(tf.getText());tf.setText(String.valueOf(i/180*Math.PI));}else{if(flag){IfResult = false;}if(IfResult){oper = str;}else{getResult(Double.parseDouble(tf.getText()) );oper = str;IfResult = true;}}}}/***清除按钮的事件监听*/class Clear implements ActionListener{ public void actionPerformed(ActionEvent e) {/** 用ActionEvent对象的getActionCommand()方法* 取得与引发事件对象相关的字符串*/String str = e.getActionCommand();if(str == "C"){tf.setText("0");IfResult = true;result = 0;}else if(str == "-/+"){double i = 0 - Double.parseDouble(tf.getText().trim());tf.setText(df.format(i));}else if(str == "Backspace"){if(Double.parseDouble(tf.getText()) > 0){if(tf.getText().length() > 1){tf.setText(tf.getText().substring(0,tf.getText().length() - 1));//使用退格删除最后一位字符}else{tf.setText("0");IfResult = true;}}else{if(tf.getText().length() > 2){tf.setText(tf.getText().substring(0,tf.getText().length() - 1));}else{tf.setText("0");IfResult = true;}}}else if(str == "CE"){tf.setText("0");IfResult = true;}}}/***数字输入的事件监听*/class Num implements ActionListener{ public void actionPerformed(ActionEvent e) {String str = e.getActionCommand(); if(IfResult){tf.setText("");IfResult = false;}if(str=="π"){tf.setText(String.valueOf(Math.PI)); }else if(str=="e"){tf.setText(String.valueOf(Math.E)); }else{tf.setText(tf.getText().trim() + str);if(tf.getText().equals("0")){tf.setText("0");IfResult = true;flag = true;}}}}/***小数点的事件监听*/class Dot implements ActionListener{ public void actionPerformed(ActionEvent e) {IfResult = false;if(tf.getText().trim().indexOf(".") == -1){tf.setText(tf.getText() + ".");}}}/***main方法*/public static void main(String[] args) { new Calucator().setVisible(true);}}。