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JAVA-复数计算器

JAVA-复数计算器

JAVA-复数计算器使⽤java组件做⼀个复数计算器⾸先，建三个类：⼀个组件类，⼀个类（将⽂本框与字符封装起来），⼀个复数类。

下⾯是组件类的代码：package b;import java.awt.*;import java.awt.event.*;import javax.swing.*;import javax.swing.event.*;public class JComplex extends JFrame implements ActionListener{//设置组件public JComboBox<String> combox_add,combox_minus;private static String[] add={"+","-"};private static String[] minus={"+","-"};private JButton button_equal;//建⾯板类的对象ComJPanel x1=new ComJPanel();ComJPanel x2=new ComJPanel();ComJPanel x3=new ComJPanel();ComJPanel result=new ComJPanel();public JComplex(){super("复数运算器");this.setLayout(null);this.setSize(400,220);this.setLocationRelativeTo(null);//添加组件this.add(box_add=new JComboBox<String>(JComplex.add));this.add(box_minus=new JComboBox<String>(JComplex.minus));this.add(this.button_equal=new JButton("="));this.add(x1);this.add(x2);this.add(x3);this.add(result);//设置组件的距离和⼤⼩combox_add.setBounds(20, 70, 60, 30);combox_minus.setBounds(20, 110, 60, 30);button_equal.setBounds(20, 150, 60, 30);x1.setBounds(100, 5, 300, 50);x2.setBounds(100, 50, 300, 50);x3.setBounds(100, 100, 300, 50);result.setBounds(100, 150, 300, 50);//设置动作监听combox_add.addActionListener(this);combox_minus.addActionListener(this);button_equal.addActionListener(this);this.setDefaultCloseOperation(EXIT_ON_CLOSE);this.setVisible(true);}public void actionPerformed(ActionEvent e){//获取⽂本框的内容String s1=x1.text_real.getText();String s2=x1.text_i.getText();String s3=x2.text_real.getText();String s4=x2.text_i.getText();String s5=x3.text_real.getText();String s6=x3.text_i.getText();//建复数类的对象Complex c1=new Complex(s1,s2);Complex c2=new Complex(s3,s4);Complex c3=new Complex(s5,s6);//动作响应if(e.getSource().equals(combox_add)){if(combox_add.getSelectedItem().equals("+")) combox_add.setSelectedItem("+");else if(combox_add.getSelectedItem().equals("-")) combox_add.getSelectedItem().equals("-");}if(e.getSource().equals(combox_minus)){if(combox_minus.getSelectedItem().equals("+")) combox_minus.setSelectedItem("+");else if(combox_minus.getSelectedItem().equals("-")) combox_minus.setSelectedItem("-");}if(e.getSource().equals(button_equal)){if(combox_add.getSelectedItem().equals("+")){c1.add(c2);}else if(combox_add.getSelectedItem().equals("-")) {c1.minus(c2);}if(combox_minus.getSelectedItem().equals("+")){c1.add(c3);}else if(combox_minus.getSelectedItem().equals("-")) {c1.minus(c3);}}result.text_real.setText(Double.toString(c1.x)); result.text_i.setText(Double.toString(c1.y));}public static void main(String []args){new JComplex();}}class ComJPanel extends JPanel {private JLabel label_add,label_i;JTextField text_real,text_i;String s1,s2;public ComJPanel(){//⾯板类this.setLayout(null);this.add(this.text_real=new JTextField());this.add(bel_add=new JLabel("+"));this.add(this.text_i=new JTextField());this.add(bel_i=new JLabel("i"));text_real.setBounds(20,0,100,30);text_i.setBounds(150,0,100, 30);label_add.setBounds(130,0,20, 25); label_i.setBounds(260,0,20, 25);}}复数类就是简单的复数类，就不贴代码啦。

计算器Java编程完全代码

计算器Java编程完全代码

计算器Java编程代码1、界面截图1、程序代码import java.awt.*;import java.awt.event.*;import javax.swing.*;public class Counter implements ActionListener {// 改进小数问题private boolean append = false;JButton[] jb = new JButton[20];JTextField jtf = new JTextField(19);String[] st = { "Backs", "CE", "C", "+", " 7 ", " 8 ", " 9", "-"," 4 ", " 5 ", " 6", "*", " 1 ", " 2 ", " 3", "/"," . ", "+/-", " 0", "=", };String num1 = "0";String operator = "+";public Counter() {JFrame jf = new JFrame("计算器");// 界面设置GridLayout gl = new GridLayout(6, 1);jf.setLayout(gl);JPanel jp0 = new JPanel();jp0.add(jtf);jf.add(jp0);JPanel jp1 = new JPanel();for (int i = 0; i < 4; i++) {jb[i] = new JButton(st[i]);jp1.add(jb[i]);}jf.add(jp1);JPanel jp2 = new JPanel();for (int i = 4; i < 8; i++) {jb[i] = new JButton(st[i]);jp2.add(jb[i]);}jf.add(jp2);JPanel jp3 = new JPanel();for (int i = 8; i < 12; i++) {jb[i] = new JButton(st[i]);jp3.add(jb[i]);}jf.add(jp3);JPanel jp4 = new JPanel();for (int i = 12; i < 16; i++) { jb[i] = new JButton(st[i]);jp4.add(jb[i]);}jf.add(jp4);JPanel jp5 = new JPanel();for (int i = 16; i < 20; i++) { jb[i] = new JButton(st[i]);jp5.add(jb[i]);}jf.add(jp5);jtf.setEditable(false);// 文本框不可编辑jf.setResizable(false);// 窗口不可编辑jf.pack();// 自动调整窗口的大小// jf.setSize(240, 220);jf.setLocation(450, 300);jf.setVisible(true);jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);for (int i = 0; i < 20; i++) {// 注册监听jb[i].addActionListener(this);}}public void actionPerformed(ActionEvent ae) {String s = ae.getActionCommand();if (s.trim().matches("^\\d$")) {// 判断是输入的是否是数字if (append) {// 追加数字String ss = jtf.getText().trim();jtf.setText(ss + s.trim());} else {// 替换文本框原来的数字jtf.setText(s.trim());append = true;}} else if ("+-/*".indexOf(s.trim()) != -1) {// 判断按的是否是四则运算符num1 = jtf.getText();// 将第一次输入的数存储起来operator = s.trim();// 将输入的符号存储起来append = false;} else if ("=".equals(s.trim())) {String num2 = jtf.getText();double d1 = Double.parseDouble(num1);double d2 = Double.parseDouble(num2);if ("+".equals(operator)) {// 加法运算d1 = d1 + d2;} else if ("-".equals(operator)) {// 减法运算d1 = d1 - d2;} else if ("*".equals(operator)) {// 乘法运算d1 = d1 * d2;} else if ("/".equals(operator)) {// 除法运算d1 = d1 / d2;}jtf.setText(d1 + "");// 显示结果append = false;} else if (".".equals(s.trim())) {// 判断小数点String temp = jtf.getText();if (temp.indexOf(".") == -1) {jtf.setText(temp + ".");append = true;}} else if ("+/-".equals(s.trim())) {// 判断+/-String temp = jtf.getText();if(temp.startsWith("-")) {// 如果该数是负数则取负号后的数字jtf.setText(temp.substring(1));} else {// 如果是正数则在这个数前加上负号jtf.setText("-" + temp);}} else if ("CE".equals(s.trim()) || "C".equals(s.trim())) {// 判断复位键jtf.setText("0");append = false;} else if ("BackS".equals(s.trim())) {// 判断BackS键（删除）String temp = jtf.getText();if (temp.length() > 0) {jtf.setText(temp.substring(0, temp.length() - 1));}}}public static void main(String[] args) {new Counter();}}。

用java代码写的简易计算器（可以实现基本的加减乘除功能）

用java代码写的简易计算器（可以实现基本的加减乘除功能）

⽤java代码写的简易计算器（可以实现基本的加减乘除功能）package A;import java.awt.*;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.awt.event.MouseEvent;import java.awt.event.MouseListener;import javax.swing.*;public class Calcular3 extends JFrame implements ActionListener,MouseListener{private int m1=0,n=0;//private double m2=0;//运算的数private int flag=0;JFrame f;JPanel p1,p2,p3;JTextField t;JButton b1[]=new JButton[18];String b[]= {"1","2","3","4","5","6","7","8","9","0","清空","退格",".","=","+","-","*","/"};public Calcular3(){f=new JFrame("计算器");t=new JTextField(35);p1=new JPanel();p2=new JPanel();p3=new JPanel();f.setBounds(100, 100, 400, 200);f.add(p1,BorderLayout.NORTH);f.add(p2,BorderLayout.CENTER);f.add(p3,BorderLayout.EAST);p2.setLayout(new GridLayout(5,3));p3.setLayout(new GridLayout(4,1));p1.add(t);for(int i=0;i<14;i++) {b1[i]=new JButton(b[i]);p2.add(b1[i]);b1[i].addActionListener(this);}for(int i=14;i<18;i++) {b1[i]=new JButton(b[i]);p3.add(b1[i]);b1[i].addActionListener(this);}/*for(int i=0;i<18;i++) {b1[i].addActionListener(this);}*/f.setVisible(true);}//实现接⼝的⽅法public void mouseClicked(MouseEvent e) {}public void mousePressed(MouseEvent e) {}public void mouseReleased(MouseEvent e) {}public void mouseEntered(MouseEvent e) {}public void mouseExited(MouseEvent e) {}public void actionPerformed(ActionEvent e) {String str="";int i;for(i=0;i<=9;i++) {if(e.getSource()==b1[i]) {if(i==9) {n=n*10;}else {n=n*10+i+1;}str=String.valueOf(n);//整形n转换成字符串strt.setText(str);//显⽰到⽂本框上}}for(i=14;i<18;i++) {//+、-、*、/if(e.getSource()==b1[i]) {//匹配运算符m1=Integer.parseInt(t.getText());if(flag==15) {m2=m1+m2;}else if(flag==16) {m2=m1-m2;}else if(flag==17) {m2=m1*m2;}else if(flag==18) {m2=m1/m2;}else m2=m1;//若⽆连续的运算符运算，保存当前数据到m2 if(i==14) flag=15;else if(i==15) flag=16;else if(i==16) flag=17;else flag=18;str=String.valueOf(b[i]);t.setText(str);//显⽰到⽂本框上n=0;//还原，记录下次数据break;//找到匹配数据退出循环}}if(e.getSource()==b1[13]) {//=m1=Integer.parseInt(t.getText());if(flag==15) {m2=m2+m1;}else if(flag==16) {m2=m2-m1;}else if(flag==17) {m2=m2*m1;}else if(flag==18) {m2=m2/m1;}else m2=m1;str=String.valueOf(m2);t.setText(str);//显⽰到⽂本框上n=0;//还原，记录下次数据flag=0;//flag还原0，表明没有未处理的运算符}if(e.getSource()==b1[10]) {//各变量变为0 清空m1=0;m2=0;flag=0;n=0;t.setText("0");//显⽰到⽂本框上}if(e.getSource()==b1[11]) {//退格m1=(int)(Double.parseDouble(t.getText())/10);n=m1;str=String.valueOf(m1);t.setText(str);}if(e.getSource()==b1[12]) {//⼩数点m1=Integer.parseInt(t.getText());str=String.valueOf(m1+b[12]);t.setText(str);//显⽰到⽂本框上int j=0;for(i=0;i<=9;i++) {if(e.getSource()==b1[i]) {j++;m2=Math.pow(0.1, j)*Integer.parseInt(b[i]);str=String.valueOf(m1+m2);t.setText(str);//显⽰到⽂本框上}}}}//主函数public static void main(String[] args) {new Calcular3();}}。

java计算器程序代码

java计算器程序代码

import java.awt.*;//计算器实例import java.awt.event.*;public class calculator{public static void main(String args[]){MyWindow my=new MyWindow("计算器");}}class MyWindow extends Frame implements ActionListener{ StringBuffer m=new StringBuffer();int p;TextField tex;Buttonb0,b1,b2,b3,b4,b5,b6,b7,b8,b9,jia,jian,cheng,chu,deng,dian,qingling,kaifang;MyWindow(String s){super(s);//StringBuffer s2=new StringBuffer();//String s;tex=new TextField(18);b0=new Button(" 0 ");b1=new Button(" 1 ");b2=new Button(" 2 ");b3=new Button(" 3 ");b4=new Button(" 4 ");b5=new Button(" 5 ");b6=new Button(" 6 ");b7=new Button(" 7 ");b8=new Button(" 8 ");b9=new Button(" 9 ");dian=new Button(" . ");jia=new Button(" + ");jian=new Button(" - ");cheng=new Button(" × ");chu=new Button(" / ");deng=new Button(" = ");qingling=new Button(" 清零 ");kaifang=new Button(" √ ");setLayout(new FlowLayout());add(tex);add(b0);add(b1);add(b2);add(b3);add(b4);add(b5);add(b6);add(b7);add(b8);add(b9);add(dian);add(jia);add(jian);add(cheng);add(chu);add(kaifang);add(qingling);add(deng);b0.addActionListener(this);b1.addActionListener(this);b2.addActionListener(this);b3.addActionListener(this);b4.addActionListener(this);b5.addActionListener(this);b6.addActionListener(this);b7.addActionListener(this);b8.addActionListener(this);b9.addActionListener(this);jia.addActionListener(this);jian.addActionListener(this);cheng.addActionListener(this);chu.addActionListener(this);dian.addActionListener(this);deng.addActionListener(this);qingling.addActionListener(this); kaifang.addActionListener(this);setBounds(200,200,160,280);setResizable(false);//不可改变大小setVisible(true);validate();addWindowListener(new WindowAdapter(){ public void windowClosing(WindowEvent ee){ System.exit(0);}});}public void actionPerformed(ActionEvent e){if(e.getSource()==b0){m=m.append("0");tex.setText(String.valueOf(m));}if(e.getSource()==b1){m=m.append("1"); tex.setText(String.valueOf(m)); }if(e.getSource()==b2){m=m.append("2"); tex.setText(String.valueOf(m)); }if(e.getSource()==b3){m=m.append("3"); tex.setText(String.valueOf(m)); }if(e.getSource()==b4){m=m.append("4"); tex.setText(String.valueOf(m));}if(e.getSource()==b5){m=m.append("5"); tex.setText(String.valueOf(m)); }if(e.getSource()==b6){m=m.append("6"); tex.setText(String.valueOf(m)); }if(e.getSource()==b7){m=m.append("7"); tex.setText(String.valueOf(m)); }if(e.getSource()==b8){m=m.append("8"); tex.setText(String.valueOf(m)); }if(e.getSource()==b9){m=m.append("9"); tex.setText(String.valueOf(m)); }if(e.getSource()==jia){m=m.append("+"); tex.setText(String.valueOf(m)); }if(e.getSource()==jian){m=m.append("-"); tex.setText(String.valueOf(m)); }if(e.getSource()==cheng){m=m.append("*"); tex.setText(String.valueOf(m)); }if(e.getSource()==chu){m=m.append("/"); tex.setText(String.valueOf(m)); }if(e.getSource()==dian){m=m.append("."); tex.setText(String.valueOf(m)); }String mm=String.valueOf(m);int p1=mm.indexOf("+");int p2=mm.indexOf("-");int p3=mm.indexOf("*");int p4=mm.indexOf("/");if(p1!=-1){p=p1;}else if(p3!=-1){p=p3;}else if(p2!=-1){p=p2;}else if(p4!=-1){p=p4;}if(e.getSource()==deng){String m1=mm.substring(0,p);String m2=mm.substring(p+1);String ch=mm.substring(p,p+1);//System.out.println(m1);//System.out.println(m2);//System.out.println(ch);if(ch.equals("+")){float n1=Float.parseFloat(m1); float n2=Float.parseFloat(m2); float sum=n1+n2;String su=String.valueOf(sum); tex.setText(su);}if(ch.equals("-")){float n1=Float.parseFloat(m1);float n2=Float.parseFloat(m2);float sum=n1-n2;String su=String.valueOf(sum);tex.setText(su);}if(ch.equals("*")){float n1=Float.parseFloat(m1);float n2=Float.parseFloat(m2);float sum=n1*n2;String su=String.valueOf(sum);tex.setText(su);}if(ch.equals("/")){float n1=Float.parseFloat(m1);float n2=Float.parseFloat(m2);float sum=n1/n2;String su=String.valueOf(sum);tex.setText(su);}}if(e.getSource()==qingling){StringBuffer kk=new StringBuffer(); m=kk;tex.setText("0");// System.out.println(mm);}if(e.getSource()==kaifang){String t=tex.getText();float num=Float.parseFloat(t);double nub=Math.sqrt(num);tex.setText(String.valueOf(nub)); }}}。

计算器完整代码(java)

计算器完整代码(java)

1． Calculator 类import java.applet.*;import java.awt.*;import java.awt.event.*;import ng.*;import java.applet.Applet;import javax.swing.*;import javax.swing.border.*;public class Calculator extends JApplet implements ActionListener {private final String[] KEYS={"7","8","9","/","sqrt", "4","5","6","*","%","1","2","3","-","1/x","0","+/-",".","+","="};private final String[] COMMAND={"Backspace","CE","C"};private final String[] M={" ","MC","MR","MS","M+"};private JButton keys[]=new JButton[KEYS.length];private JButton commands[]=new JButton[COMMAND.length];private JButton m[]=new JButton[M.length];private JTextField display =new JTextField("0");// public JTextField setHorizontalAlignment(int alignment);// private JTextFielddisplay.setHorizontalAlignment(JTextField.RIGHT)=new JTextField("0"); private void setup(){display.setHorizontalAlignment(JTextField.RIGHT);JPanel calckeys=new JPanel();JPanel command=new JPanel();JPanel calms=new JPanel();calckeys.setLayout(new GridLayout(4,5,3,3));command.setLayout(new GridLayout(1,3,3,3));calms.setLayout(new GridLayout(5,1,3,3));for(int i=0;i<KEYS.length;i++){keys[i]=new JButton(KEYS[i]);calckeys.add(keys[i]);keys[i].setForeground(Color.blue);}keys[3].setForeground(Color.red);keys[4].setForeground(Color.red);keys[8].setForeground(Color.red);keys[9].setForeground(Color.red);keys[13].setForeground(Color.red);keys[14].setForeground(Color.red);keys[18].setForeground(Color.red);keys[19].setForeground(Color.red);for(int i=0;i<COMMAND.length;i++){commands[i]=new JButton(COMMAND[i]);command.add(commands[i]);commands[i].setForeground(Color.red);}for(int i=0;i<M.length;i++){m[i]=new JButton(M[i]);calms.add(m[i]);m[i].setForeground(Color.red);}JPanel panel1=new JPanel();panel1.setLayout(new BorderLayout(3,3));panel1.add("North",command);panel1.add("Center",calckeys);JPanel top=new JPanel();top.setLayout(new BorderLayout());display.setBackground(Color.WHITE);top.add("Center",display);getContentPane().setLayout(new BorderLayout(3,5)); getContentPane().add("North",top);getContentPane().add("Center",panel1); getContentPane().add("West",calms);}public void init(){setup();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);}display.setEditable(false);}public void actionPerformed(ActionEvent e){String label=e.getActionCommand();// double zero=e.getActionCommand();if(label=="C")handleC();else if(label=="Backspace")handleBackspace();else if(label=="CE")display.setText("0");else if (label=="1/x")daoShu();else if(label=="sqrt"){display.setText(Math.sqrt(getNumberFromDisplay())+"");}else if("0123456789.".indexOf(label)>=0){handleNumber(label);// handlezero(zero);}elsehandleOperator(label);}private boolean firstDigit=true;private void handleNumber(String key){if(firstDigit){ if(key.equals("0"))display.setText(key);else if(key.equals(".")){display.setText("0.");firstDigit=false;}else if(!key.equals("0")&&!key.equals(".")){display.setText(key);firstDigit=false;}}else if((key.equals("."))&&(display.getText().indexOf(".")<0)) display.setText(display.getText()+".");else if(!key.equals(".")&&display.getText().length()<=32) display.setText(display.getText()+key);}private double number=0;private String operator="=";private void handleOperator(String key){if(operator.equals("/")){if(getNumberFromDisplay()==0){display.setText("除数不能为零");}else{number/=getNumberFromDisplay();}long t1;double t2;t1=(long)number;t2=number-t1;if(t2==0){display.setText(String.valueOf(t1));}else{display.setText(String.valueOf(number));}}else if(operator.equals("+"))number+=getNumberFromDisplay();else if(operator.equals("-"))number-=getNumberFromDisplay();else if(operator.equals("*"))number*=getNumberFromDisplay();else if(operator.equals("%"))number=number/100;else if(operator.equals("+/-"))number=number*(-1);else if(operator.equals("="))number=getNumberFromDisplay();long t1;double t2;t1=(long)number;t2=number-t1;if(t2==0)display.setText(String.valueOf(t1));elsedisplay.setText(String.valueOf(number));operator=key;firstDigit=true;}private double getNumberFromDisplay(){return Double.valueOf(display.getText()).doubleValue(); }private void handleC(){display.setText("0");firstDigit=true;operator="=";}private void handleBackspace(){String text=display.getText();int i=text.length();if(i>0){text=text.substring(0,i-1);if(text.length()==0){display.setText("0");firstDigit=true;operator="=";}elsedisplay.setText(text);}}private void daoShu(){if (display.getText().equals("0")){display.setText("除数不能为零");System.out.println(1);}else{long l;double d=1/getNumberFromDisplay();l=(long)d;System.out.println(d);System.out.println(l);display.setText(String.valueOf(d));}}}2.CalFrame 类import java.awt.Color;importimport java.awt.event.ActionListener;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import javax.swing.JApplet;import javax.swing.JFrame;public class Test {public static void main(String[] args) {JFrame f=new JFrame();f.getAccessibleContext();Calculator Calculator1=new Calculator(); Calculator1.init();f.getContentPane().add("Center",Calculator1);f.setVisible(true);f.setBounds(300, 200,380,245);f.setBackground(Color.LIGHT_GRAY);f.validate();f.setResizable(false);f.addWindowListener(new WindowAdapter(){public void windowClosing(WindowEvent e){System.exit(0);}});f.setTitle("计算器");}}。

java计算器设计实验报告

java计算器设计实验报告

java计算器设计实验报告《Java计算器设计实验报告》摘要：本实验报告基于Java语言，设计了一个简单的计算器。

通过使用面向对象的编程方法，实现了基本的加、减、乘、除运算，并且实现了用户界面的交互操作。

本实验报告详细介绍了计算器的设计思路、实现过程和代码结构，并对实验结果进行了分析和总结。

1. 引言计算器是人们日常生活中常用的工具之一，它能够帮助人们进行简单的数学运算。

随着计算器的普及和发展，计算器的功能也越来越丰富，例如科学计算器、金融计算器等。

本实验旨在通过使用Java语言，设计一个简单的计算器，以加深对面向对象编程的理解和应用。

2. 设计思路在设计计算器时，首先需要确定计算器的功能需求，包括加法、减法、乘法、除法等基本运算。

其次，需要考虑用户界面的设计，使用户能够方便地输入数字和选择运算符。

最后，需要考虑计算器的实现方式，包括数据结构的选择、算法的设计等。

3. 实现过程在本实验中，我们使用Java语言和Swing库来实现计算器的设计。

首先，我们创建一个Calculator类来处理计算器的逻辑操作，包括加法、减法、乘法、除法等运算。

然后，我们创建一个CalculatorUI类来处理用户界面的设计，包括数字按钮、运算符按钮和显示屏的设计。

最后，我们将Calculator类和CalculatorUI类进行整合，实现一个完整的计算器。

4. 代码结构以下是计算器的主要代码结构：Calculator类：- add(double a, double b)：加法运算- subtract(double a, double b)：减法运算- multiply(double a, double b)：乘法运算- divide(double a, double b)：除法运算CalculatorUI类：- createNumberButton(int number)：创建数字按钮- createOperatorButton(String operator)：创建运算符按钮- createDisplayScreen()：创建显示屏Main类：- main(String[] args)：主函数，启动计算器界面5. 实验结果分析通过实验，我们成功地实现了一个简单的计算器，用户能够输入数字并进行加、减、乘、除等运算。

java计算器源代码(仿win7)

java计算器源代码(仿win7)import java.awt.*;import javax.swing.*;import java.awt.event.*;class Cal extends JFrame implements ActionListener,MouseListener{JMenuBar menubar;JMenu menu_check,menu_edit,menu_help;JMenuItem menuitem_science,menuitem_check,menuitem_exit,menuitem_copy,menuitem_paste,menuitem1_copy,menuitem1_paste,menuitem_chelp,menuitem_about;JCheckBoxMenuItem menuitem_standard;JTextField ta1;int x,result2;double op1,op2,opall;private boolean end=false,flag=false,add=false,sub=false,cheng=false,chu=false,flagop2=false;JButton b_mc,b_mr,b_ms,b_mjia,b_mjian,b_tui,b_ce,b_c,b_jj,b_dui,b_7,b_8,b_9,b_chu,b_baifenhao,b_4,b_5,b_6,b_cheng,b_daoshu,b_1,b_2,b_3,b_jian,b_0,b_dian,b_jia,b_dengyu;JPanel p_all,p_button1,p_button2,p_txt,p1,p2,p3,p4,p5;private String str,resultstr;JPopupMenu popupmenu;Container con=this.getContentPane();Font font=new Font("微软雅黑",Font.PLAIN,12);Color color=new Color(120,220,120);Cal(String s){super(s);setSize(220,315);setResizable(false);setVisible(true);Dimension scr=Toolkit.getDefaultToolkit().getScreenSize();Dimension frm=this.getSize();setLocation((scr.width-frm.width)/2,(scr.height-frm.height)/2);Toolkit tk=Toolkit.getDefaultToolkit();//程序默认图标设置setIconImage(tk.createImage("D:\\sd.jpg"));setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//-----------------------------------------------------------------制作框架结构------------------------- //---------------------------------------菜单栏---------------------------menubar=new JMenuBar();menubar.setPreferredSize(new Dimension(frm.width,19));menu_check=new JMenu("查看(V)");menu_check.setFont(font);menu_check.setForeground(Color.black);menuitem_standard=new JCheckBoxMenuItem("标准型",true);menuitem_standard.setFont(font);menuitem_standard.setForeground(Color.black);menuitem_science=new JMenuItem("科学型");menuitem_science.setFont(font);menuitem_science.setForeground(Color.black);menuitem_check=new JMenuItem("查看分组");menuitem_check.setFont(font);menuitem_check.setForeground(Color.black);menuitem_exit=new JMenuItem("退出");menuitem_exit.setFont(font);menuitem_exit.setForeground(Color.black);menuitem_exit.addActionListener(this);menu_check.add(menuitem_standard);menu_check.add(menuitem_science);menu_check.addSeparator();menu_check.add(menuitem_check);menu_check.addSeparator();menu_check.add(menuitem_exit);menubar.add(menu_check);menu_edit=new JMenu("编辑(E)");menu_edit.setFont(font);menu_edit.setForeground(Color.black);menu_edit.setMnemonic(KeyEvent.VK_E);menuitem_copy=new JMenuItem("复制(C) ");menuitem_copy.setFont(font);menuitem_copy.setForeground(Color.black);menuitem_copy.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C,InputEvent.CTRL_M ASK));menuitem_copy.addActionListener(this);menuitem_paste=new JMenuItem("粘贴(P) ");menuitem_paste.setFont(font);menuitem_paste.setForeground(Color.black);menuitem_paste.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_V,InputEvent.CTRL_M ASK));menuitem_paste.addActionListener(this);menu_edit.add(menuitem_copy);menu_edit.add(menuitem_paste);menubar.add(menu_edit);menu_help=new JMenu("帮助(H)");menu_help.setFont(font);menu_help.setForeground(Color.black);menuitem_chelp=new JMenuItem("查看帮助");menuitem_chelp.setFont(font);menuitem_chelp.setForeground(Color.black);menuitem_about=new JMenuItem("关于计算器");menuitem_about.setFont(font);menuitem_about.setForeground(Color.black);menuitem_about.addActionListener(this);menu_help.add(menuitem_chelp);menu_help.addSeparator();menu_help.add(menuitem_about);menubar.add(menu_help);setJMenuBar(menubar);//--------------------------------------文本框----------------------------------ta1=new JTextField("0");ta1.setFont(new Font("微软雅黑",Font.PLAIN,13));ta1.setEditable(false);//ta1.setOpaque(false);ta1.setHorizontalAlignment(JTextField.RIGHT);ta1.setPreferredSize(new Dimension((frm.width-26),45));ta1.addMouseListener(this);p_all=new JPanel();p_all.setPreferredSize(new Dimension((frm.width-6),250));//p_all.setBackground(color);p_all.setLayout(new FlowLayout(FlowLayout.CENTER,0,3));p_txt=new JPanel();p_txt.setPreferredSize(new Dimension((frm.width-6),53));p_txt.setLayout(new FlowLayout(FlowLayout.CENTER,0,7));p_txt.add(ta1);p_all.add(p_txt);con.add(p_all,BorderLayout.CENTER);//-------------------------------------按钮区----------------------------------p_button1=new JPanel();p_button1.setPreferredSize(new Dimension((frm.width-25),131)); p_button1.setLayout(new FlowLayout(FlowLayout.LEFT,0,3));p_all.add(p_button1);p1=new JPanel();p1.setPreferredSize(new Dimension((frm.width-25),127));p1.setLayout(new GridLayout(4,5,5,6));b_mc=new JButton("MC");b_mc.setFont(new Font("微软雅黑",Font.PLAIN,11));b_mc.setMargin(new Insets(0,0,0,0));b_mc.setForeground(Color.blue);b_mc.addActionListener(this);b_mr=new JButton("MR");b_mr.setFont(new Font("微软雅黑",Font.PLAIN,11));b_mr.setMargin(new Insets(0,0,0,0));b_mr.setForeground(Color.blue);b_mr.addActionListener(this);b_ms=new JButton("MS");b_ms.setFont(new Font("微软雅黑",Font.PLAIN,11));b_ms.setMargin(new Insets(0,0,0,0));b_ms.setForeground(Color.blue);b_ms.addActionListener(this);b_mjia=new JButton("M+");b_mjia.setFont(new Font("微软雅黑",Font.PLAIN,11));b_mjia.setMargin(new Insets(0,0,0,0));b_mjia.setForeground(Color.blue);b_mjia.addActionListener(this);b_mjian=new JButton("M-");b_mjian.setFont(new Font("微软雅黑",Font.PLAIN,11)); b_mjian.setMargin(new Insets(0,0,0,0));b_mjian.setForeground(Color.blue);b_mjian.addActionListener(this);b_tui=new JButton("←");b_tui.setFont(new Font("微软雅黑",Font.BOLD,14));b_tui.setMargin(new Insets(0,0,0,0));b_tui.addActionListener(this);b_tui.setForeground(Color.red);b_ce=new JButton("CE");b_ce.setFont(new Font("微软雅黑",Font.PLAIN,11));b_ce.setMargin(new Insets(0,0,0,0));b_ce.setForeground(Color.red);b_ce.addActionListener(this);b_c=new JButton("C");b_c.setFont(new Font("微软雅黑",Font.PLAIN,11));b_c.setMargin(new Insets(0,0,0,0));b_c.setForeground(Color.red);b_c.addActionListener(this);b_jj=new JButton("±");b_jj.setFont(new Font("微软雅黑",Font.PLAIN,14));b_jj.setMargin(new Insets(0,0,0,0));b_jj.setForeground(Color.red);b_jj.addActionListener(this);b_dui=new JButton("√");b_dui.setFont(new Font("微软雅黑",Font.PLAIN,11)); b_dui.setMargin(new Insets(0,0,0,0));b_dui.setForeground(Color.red);b_dui.addActionListener(this);b_7=new JButton("7");b_7.setFont(new Font("微软雅黑",Font.PLAIN,14));b_7.setMargin(new Insets(0,0,0,0));b_7.setForeground(Color.blue);b_7.setMnemonic(KeyEvent.VK_7);b_7.addActionListener(this);b_8=new JButton("8");b_8.setFont(new Font("微软雅黑",Font.PLAIN,14));b_8.setMargin(new Insets(0,0,0,0));b_8.setForeground(Color.blue);b_8.setMnemonic(KeyEvent.VK_8);b_8.addActionListener(this);b_9=new JButton("9");b_9.setMargin(new Insets(0,0,0,0));b_9.setForeground(Color.blue);b_9.setMnemonic(KeyEvent.VK_9);b_9.addActionListener(this);b_chu=new JButton("/");b_chu.setFont(new Font("微软雅黑",Font.PLAIN,14));b_chu.setMargin(new Insets(0,0,0,0));b_chu.setForeground(Color.red);b_chu.addActionListener(this);b_baifenhao=new JButton("%");b_baifenhao.setFont(new Font("微软雅黑",Font.PLAIN,11)); b_baifenhao.setMargin(new Insets(0,0,0,0));b_baifenhao.setForeground(Color.blue);b_baifenhao.addActionListener(this);b_4=new JButton("4");b_4.setFont(new Font("微软雅黑",Font.PLAIN,14));b_4.setMargin(new Insets(0,0,0,0));b_4.setForeground(Color.blue);b_4.setMnemonic(KeyEvent.VK_4);b_4.addActionListener(this);b_5=new JButton("5");b_5.setFont(new Font("微软雅黑",Font.PLAIN,14));b_5.setMargin(new Insets(0,0,0,0));b_5.setForeground(Color.blue);b_5.setMnemonic(KeyEvent.VK_5);b_5.addActionListener(this);b_6=new JButton("6");b_6.setFont(new Font("微软雅黑",Font.PLAIN,14));b_6.setMargin(new Insets(0,0,0,0));b_6.setForeground(Color.blue);b_6.setMnemonic(KeyEvent.VK_6);b_6.addActionListener(this);b_cheng=new JButton("*");b_cheng.setFont(new Font("微软雅黑",Font.PLAIN,14));b_cheng.setMargin(new Insets(0,0,0,0));b_cheng.setForeground(Color.red);b_cheng.addActionListener(this);b_daoshu=new JButton("1/x");b_daoshu.setFont(new Font("微软雅黑",Font.PLAIN,11)); b_daoshu.setMargin(new Insets(0,0,0,0));b_daoshu.setForeground(Color.blue);b_daoshu.addActionListener(this);b_1=new JButton("1");b_1.setMargin(new Insets(0,0,0,0));b_1.setForeground(Color.blue);b_1.setMnemonic(KeyEvent.VK_1);b_1.addActionListener(this);b_2=new JButton("2");b_2.setFont(new Font("微软雅黑",Font.PLAIN,14)); b_2.setMargin(new Insets(0,0,0,0));b_2.setForeground(Color.blue);b_2.setMnemonic(KeyEvent.VK_2);b_2.addActionListener(this);b_3=new JButton("3");b_3.setFont(new Font("微软雅黑",Font.PLAIN,14)); b_3.setMargin(new Insets(0,0,0,0));b_3.setForeground(Color.blue);b_3.setMnemonic(KeyEvent.VK_3);b_3.addActionListener(this);b_jian=new JButton("-");b_jian.setFont(new Font("微软雅黑",Font.PLAIN,14)); b_jian.setMargin(new Insets(0,0,0,0));b_jian.setForeground(Color.red);b_jian.addActionListener(this);b_0=new JButton("0");b_0.setFont(new Font("微软雅黑",Font.PLAIN,14)); b_0.setMargin(new Insets(0,0,0,0));b_0.setPreferredSize(new Dimension(75,27));b_0.setForeground(Color.blue);b_0.setMnemonic(KeyEvent.VK_0);b_0.addActionListener(this);JLabel L1=new JLabel();L1.setPreferredSize(new Dimension(5,3));b_dian=new JButton(".");b_dian.setFont(new Font("微软雅黑",Font.BOLD,14)); b_dian.setMargin(new Insets(0,0,0,0));b_dian.setPreferredSize(new Dimension(35,27));b_dian.setForeground(Color.blue);b_dian.addActionListener(this);JLabel L2=new JLabel();L2.setPreferredSize(new Dimension(5,3));b_jia=new JButton("+");b_jia.setFont(new Font("微软雅黑",Font.BOLD,14)); b_jia.setMargin(new Insets(0,0,0,0));b_jia.setPreferredSize(new Dimension(35,27));b_jia.setForeground(Color.red);b_jia.addActionListener(this);b_dengyu=new JButton("=");b_dengyu.setFont(new Font("微软雅黑",Font.BOLD,22));b_dengyu.setMargin(new Insets(0,0,0,0));b_dengyu.setPreferredSize(new Dimension(35,60));b_dengyu.setForeground(Color.blue);b_dengyu.addActionListener(this);p1.add(b_mc);p1.add(b_mr);p1.add(b_ms);p1.add(b_mjia);p1.add(b_mjian);p1.add(b_tui);p1.add(b_ce);p1.add(b_c);p1.add(b_jj);p1.add(b_dui);p1.add(b_7);p1.add(b_8);p1.add(b_9);p1.add(b_chu);p1.add(b_baifenhao);p1.add(b_4);p1.add(b_5);p1.add(b_6);p1.add(b_cheng);p1.add(b_daoshu);p_button1.add(p1);p_button2=new JPanel();p_button2.setPreferredSize(new Dimension((frm.width-24),65)); p_button2.setLayout(new FlowLayout(FlowLayout.LEFT,0,0));p_all.add(p_button2);p2=new JPanel();p2.setPreferredSize(new Dimension(156,65));p2.setLayout(new FlowLayout(FlowLayout.LEFT,0,1));p3=new JPanel();p3.setPreferredSize(new Dimension(39,62));p3.setLayout(new FlowLayout(FlowLayout.LEFT,4,0));p_button2.add(p2);p_button2.add(p3);p4=new JPanel();p4.setPreferredSize(new Dimension(156,27));p4.setLayout(new GridLayout(1,4,5,5));p5=new JPanel();p5.setPreferredSize(new Dimension(156,39));p5.setLayout(new FlowLayout(FlowLayout.LEFT,0,5));p2.add(p4);p2.add(p5);p4.add(b_1);p4.add(b_2);p4.add(b_3);p4.add(b_jian);p5.add(b_0);p5.add(L1);p5.add(b_dian);p5.add(L2);p5.add(b_jia);p3.add(b_dengyu);//---------------------------------------快捷菜单对象-------------------------popupmenu=new JPopupMenu(); //快捷菜单对象menuitem1_copy=new JMenuItem("复制");menuitem1_copy.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_C,InputEvent.CTRL_ MASK));menuitem1_copy.addActionListener(this); //监视鼠标右击菜单”复制“popupmenu.add(menuitem1_copy);menuitem1_paste=new JMenuItem("粘贴");menuitem1_paste.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_V,InputEvent.CTRL_MASK));menuitem1_paste.addActionListener(this); //监视鼠标右击菜单”粘贴“popupmenu.add(menuitem1_paste);ta1.add(popupmenu);con.validate();validate();}//---------------------------------------功能区------------------------------------public void actionPerformed(ActionEvent e){if(e.getSource()==menuitem_about){JOptionPane.showMessageDialog(null,"这是一个模仿win7的计算器！欢迎改进，\n创作者：钟作明","仿win7计算器",RMATION_MESSAGE);}if(e.getSource()==menuitem1_copy){ta1.selectAll();ta1.copy();}else if(e.getSource()==menuitem1_paste){ta1.setEditable(true);ta1.setText("");ta1.paste();ta1.setEditable(false);}else if(e.getSource()==menuitem_copy){ta1.selectAll();ta1.copy();}else if(e.getSource()==menuitem_paste){ta1.setEditable(true);ta1.setText("");ta1.paste();ta1.setEditable(false);}else if(e.getSource()==menuitem_exit){System.exit(0);}else if(e.getSource()==b_ce){ta1.setEditable(true);ta1.setText("0");ta1.setEditable(false);}else if(e.getSource()==b_c){ta1.setEditable(true);ta1.setText("0");ta1.setEditable(false);}else if(e.getSource()==b_tui){String str=ta1.getText();StringBuffer s=new StringBuffer(str);int L=s.length();try{if(L!=1){s=s.deleteCharAt(L-1);}else{s=new StringBuffer("0");}}catch(Exception e1){}ta1.setText(String.valueOf(s));}//---------------------------------------------数字键----------------------------- if(e.getSource()==b_1){addString(1);}else if(e.getSource()==b_2){addString(2);}else if(e.getSource()==b_3){addString(3);}else if(e.getSource()==b_4){addString(4);}else if(e.getSource()==b_5){addString(5);}else if(e.getSource()==b_6){addString(6);}else if(e.getSource()==b_7){addString(7);}else if(e.getSource()==b_8){addString(8);}else if(e.getSource()==b_9){addString(9);}else if(e.getSource()==b_0){addString(0);}else if(e.getSource()==b_dian){StringBuffer s1=new StringBuffer(ta1.getText());StringBuffer dian=new StringBuffer(".");if(String.valueOf(s1).indexOf(".")==-1){s1.append(dian);}ta1.setText(String.valueOf(s1));}else if(e.getSource()==b_jj){String txt=ta1.getText();int result=Integer.parseInt(txt);if(txt.indexOf("-")==-1&&txt.length()>0){if(result!=0){txt="-"+txt;}}else{StringBuffer txt1=new StringBuffer(txt);txt1=txt1.deleteCharAt(0);txt=String.valueOf(txt1);}ta1.setText(txt);}else if(e.getSource()==b_dui){str=ta1.getText();Double d=Double.parseDouble(str);if(d>=0){double d1=Math.sqrt(d);String s = String.valueOf(d1);if(s.endsWith(".0")==true){int z=(int)d1;str=String.valueOf(z);}else{str=String.valueOf(d1);}ta1.setText(str);}else{JOptionPane.showMessageDialog(null,"根号底数不能为负数","提醒", RMATION_MESSAGE);}end=true;}else if(e.getSource()==b_baifenhao){str=ta1.getText();Double d=Double.parseDouble(str);ta1.setText(""+d/100);end=true;}else if(e.getSource()==b_daoshu){str=ta1.getText();Double d=Double.parseDouble(str);if(d!=0){ta1.setText(""+1/d);}else{JOptionPane.showMessageDialog(null,"除数不能为零","提醒", RMATION_MESSAGE);}end=true;}else if(e.getSource()==b_jia){str = ta1.getText();op1 = Double.parseDouble(str);end=true;x=0;opall=op1;flagop2=false;}else if(e.getSource()==b_jian){str = ta1.getText();op1 = Double.parseDouble(str);end=true;x=1;opall=op1;flagop2=false;}else if(e.getSource()==b_cheng){str = ta1.getText();op1 = Double.parseDouble(str);end=true;x=2;opall=op1;flagop2=false;}else if(e.getSource()==b_chu){str = ta1.getText();op1 = Double.parseDouble(str);end=true;x=3;opall=op1;flagop2=false;}else if(e.getSource()==b_dengyu){str = ta1.getText();if(flagop2==false){op2 = Double.parseDouble(str);flagop2=true;}switch(x){case 0 :opall=opall+op2;String s=String.valueOf(opall);if(s.endsWith(".0")==true){result2=(int)opall;resultstr=String.valueOf(result2);}else{resultstr=String.valueOf(opall);}ta1.setText(resultstr);break;case 1 :opall=opall-op2;s=String.valueOf(opall);if(s.endsWith(".0")==true){result2=(int)opall;resultstr=String.valueOf(result2);}else{resultstr=String.valueOf(opall);}ta1.setText(resultstr);break;case 2 :opall=opall*op2;s=String.valueOf(opall);if(s.endsWith(".0")==true){result2=(int)opall;resultstr=String.valueOf(result2);}else{resultstr=String.valueOf(opall);}ta1.setText(resultstr);break;case 3 :opall=opall/op2;s=String.valueOf(opall);if(s.endsWith(".0")==true){result2=(int)opall;resultstr=String.valueOf(result2);}else{resultstr=String.valueOf(opall);}ta1.setText(resultstr);break;}end=true;}}public void addString(int num){String s=null;s=String.valueOf(num);//如果end==true;,那么屏幕清空if(end==true){ta1.setText("0");end=false;}if((ta1.getText()).equals("0")){ta1.setText(s);}else{if(ta1.getText().length()<21){str=ta1.getText()+s;ta1.setText(str);}}}public void mouseClicked(MouseEvent mec){if(mec.getModifiers()==mec.BUTTON3_MASK){popupmenu.show(ta1,mec.getX(),mec.getY());}}public void mousePressed(MouseEvent ms){}public void mouseReleased(MouseEvent md){}public void mouseEntered(MouseEvent ms){}public void mouseExited(MouseEvent mex){}public void mouseDragged(MouseEvent med){}}public class Calculator {public static void main(String[] args) {// TODO Auto-generated method stubCal jishuanji=new Cal("计算器");}}。

java计算器实验报告

课程设计论文设计题目：java计算器学生姓名：指导教师：专业名称：所在院系：摘要在当今这个网络的时代，java语言在网络编程方面的优势使得网络编程有了更好的选择。

Java语言最大的特点是具有跨平台性，使其不受平台不同的影响，得到了广泛的应用。

该程序是一个图形界面的java 计算器,其界面主要采用了swing包，程序实现了：（1）实现简单加、减、乘、除的运算。

（2）实现除了加、减、乘、除按钮外其他按钮功能。

（3）给软件添加一个编辑、查看、帮助的主菜单。

（4）在数据输入方面，提高程序代码的健壮性，增强其对非法输入数据的识别能力。

（5）科学型计算器与标准计算器之间的菜单切换。

Java的早期版本以来，抽象窗口工具包为用户界面组件提供了平台独立的API。

在AWT中，每个组件都由一个原生的等同组件生成和控制，这个原生组件是由当前的图形窗口系统决定的。

与此相对，Swing 组件经常被描述为轻量级的，因为它们不需要操作系统本身所带窗口工具包的原生资源来生成。

目录第1章概要设计 (1)1.1查找资料 (1)1.2选题 (1)1.3标准型计算器界面设计 (1)1.4本章小节 (3)第2章程序整体设计说明 (4)2.1程序中所用到的变量 (4)2.2程序部分源代码及注释 (4)2.3本章小节 (15)第3章程序运行效果 (16)3.1程序运行主界面 (16)3.2程序中各按钮运行界面 (16)3.3本章小节 (20)第4章设计中遇到的重点及难点 (21)4.1设计中遇到的重点 (21)4.2设计中的遇到的难点 (21)4.3本章小节 (23)第5章本次设计中存在不足与改良方案 (24)5.1本次设计中存在的不足 (24)5.2本次设计的改良方案 (24)5.3本章小节 (24)结论 (25)参考文献 (26)致谢 (27)指导教师评语 (28)答辩委员会评语 (29)第1章概要设计1.1查找资料21世纪，随着社会经济的迅速发展和科学技术的全面进步，人类社会已进入信息和网络时代。

JAVA计算器

import java.awt.*;import java.awt.event.*;import javax.swing.*;public class jisuanqi extends JFrame implements ActionListener,ItemListener{//ItemListener用于捕获带有item的组件产生的事件JTextField text;JTextField textMemory;//内存中记录boolean clickable;double memoryd;int memoryi;String copy;public jisuanqi(){super("计算器");setSize(450,230);}public void init(){clickable = true;JPanel pa1=new JPanel();pa1.setBackground(new Color(236,231,210));//设置背景色text=new JTextField("0.",38);//设置文本框长度text.setHorizontalAlignment(JTextField.RIGHT);//从右到左pa1.add("North",text);//面板添加和按钮的设置JPanel pa=new JPanel();JPanel pa2=new JPanel();JButton bt1=new JButton("Backspace");JButton bt2=new JButton("CE");JButton bt3=new JButton("c");bt3.setForeground(Color.red);bt3.setBackground(Color.gray);JButton bt4=new JButton("π");bt1.addActionListener(this);//添加监听器bt2.addActionListener(this);bt3.addActionListener(this);bt4.addActionListener(this);pa2.add(bt1);pa2.add(bt2);pa2.add(bt3);pa2.add(bt4);pa2.setLayout(new GridLayout(1,5));pa.setLayout(new BorderLayout());pa.add(pa2,"North");JPanel p1=new JPanel();p1.setLayout(new GridLayout(5,2));JButton bt5=new JButton("sin");JButton bt6=new JButton("cos");JButton bt7=new JButton("MC");JButton bt9=new JButton("MR");JButton bt11=new JButton("MS");JButton bt13=new JButton("M+");JButton bt12=new JButton("n!");JButton bt14=new JButton("%");JButton bt8=new JButton("x²");JButton bt10=new JButton("x³");bt5.addActionListener(this);//THIS的意思是指调用该类的实例对象bt6.addActionListener(this);bt7.addActionListener(this);bt8.addActionListener(this);bt9.addActionListener(this);bt10.addActionListener(this);bt11.addActionListener(this);bt12.addActionListener(this);bt13.addActionListener(this);bt14.addActionListener(this);p1.add(bt5);p1.add(bt6);p1.add(bt7);p1.add(bt8);p1.add(bt9);p1.add(bt10);p1.add(bt11);p1.add(bt12);p1.add(bt13);p1.add(bt14);pa.add(p1,"West");JPanel p = new JPanel();p.setLayout(new GridLayout(5, 5));String buttons[] = {"tan","cot","sinh","cosh","tanh","7","8","9","/","sqrt","4","5","6","*","Mod","1","2","3","-","1/x" ,"0","+/-",".","+","="};JButton btn[]=new JButton[buttons.length];for (int i = 0; i < buttons.length; i++){addButton(p, buttons[i]);pa.add(p, "Center");}pa1.add("South",pa);this.getContentPane().add(pa1);}private void addButton(Container c, String s){ JButton b = new JButton(s);c.add(b);b.addActionListener(this);}//功能的实现public void actionPerformed(ActionEvent evt){String s = evt.getActionCommand();if(s.equals("CE")||s.equals("C")){text.setText("");}////////////////////else if(s.equals("+/-"))//单击"+/-"选择输入的运算数是正数还是负数{ double x;x=Double.parseDouble(text.getText().trim());text.setText(""+(-x));}elseif (s == "sqrt") {String s1 = text.getText();if (s1.charAt(0) == '-'&& clickable == true) {text.setText("负数不能开根号");clickable = false;}elsetext.setText(Double.toString(ng.Math.sqrt(Double.parseDouble(text.getText()))));}else if(s.equals("x²"))//单击了"x²"按钮{ double x;x=Double.parseDouble(text.getText().trim());text.setText(""+(x*x));}else if(s.equals("x³"))//单击了"x³"按钮{ double x;x=Double.parseDouble(text.getText().trim());text.setText(""+(x*x*x));}else if(s.equals("n!"))//单击了"n!"按钮{ double x;double y=1.0;x=Double.parseDouble(text.getText().trim());for(int i=1;i<=x;i++){y*=i;}text.setText(""+y);}else if(s.equals("%"))//单击了"%"按钮{ double x;x=Double.parseDouble(text.getText().trim());text.setText(""+(x*0.01));}else if(s.equals("π"))//单击了"π"按钮{ double x;x=Double.parseDouble(text.getText().trim());x=x*Math.PI;text.setText(""+x);}else if(s.equals("sin"))//单击了"sin"按钮{ double x;x=Double.parseDouble(text.getText().trim()); //获取文本框中内容功能除去字符串开头和末尾的空格或其他字符x=Math.sin(x*Math.PI/180);text.setText(""+x);}else if(s.equals("cos"))//单击了"cos"按钮{ double x;x=Double.parseDouble(text.getText().trim());x=Math.cos(x*Math.PI/180);text.setText(""+x);}else if(s.equals("tan"))//单击了"tan"按钮{ double x;x=Double.parseDouble(text.getText().trim());x=Math.tan(x*Math.PI/180);text.setText(""+x);}else if(s.equals("cot"))//单击了"sin"按钮{ double x;x=Double.parseDouble(text.getText().trim()); //获取文本框中内容功能除去字符串开头和末尾的空格或其他字符x=1/(Math.tan(x*Math.PI/180));text.setText(""+x);}else if(s.equals("sinh"))//单击了"sinh"按钮{ double x;x=Double.parseDouble(text.getText().trim());x=Math.asin(x)*(180/Math.PI);text.setText(""+x);}else if(s.equals("cosh"))//单击了"cosh"按钮{ double x;x=Double.parseDouble(text.getText().trim());x=Math.acos(x)*(180/Math.PI);text.setText(""+x);}else if(s.equals("tanh"))//单击了"tanh"按钮{ double x;x=Double.parseDouble(text.getText().trim());x=Math.atan(x)*(180/Math.PI);text.setText(""+x);}else if(s.equals("1/x"))//单击了"1/X"按钮{ double x;x=Double.parseDouble(text.getText().trim());if(x==0){text.setText("除数不能为零");}else{text.setText(""+(1/x));}//按下'+/-'按钮时处理if (s== "+/-" && clickable == true) {boolean isNumber = true;String s1 = text.getText();for (int i = 0; i < s.length(); i++)if (! (s1.charAt(i) >= '0' && s1.charAt(i) <= '9' || s1.charAt(i) == '.' ||s1.charAt(i) == '-')) {isNumber = false;break;}if (isNumber == true) {//如果当前字符串首字母有'-'号,代表现在是个负数,再按下时,则将首符号去掉if (s.charAt(0) == '-') {text.setText("");for (int i = 1; i < s1.length(); i++) {char a = s1.charAt(i);text.setText(text.getText() + a);}}//如果当前字符串第一个字符不是符号，则添加一个符号在首字母处elsetext.setText('-' + s);}}//计算器有关内存操作//'MC'的操作，将内存清0elseif (s == "MC" && clickable == true) {memoryd = memoryi = 0;textMemory.setText("");}//'MS'的操作，将当前文本框内容保存入内存，显示'M'elseif (s == "MS" && clickable == true) {boolean isDot = false;textMemory.setText(" M");for (int i = 0; i < text.getText().length(); i++)if ('.' == text.getText().charAt(i)) {isDot = true;break;}//如果是double,则存入memoryd(double存储器)if (isDot == true) {memoryd = Double.parseDouble(text.getText());memoryi = 0; //保证存储器中存放最新的值}//如果是int,则存入memoryi(int存储器)else {memoryi = Integer.parseInt(text.getText());memoryd = 0; //保证存储器中存放最新的值}}//'MR'的操作，将存储器中的信息输出elseif (s == "MR" && clickable == true) {if (memoryd != 0)text.setText(Double.toString(memoryd));if (memoryi != 0)text.setText(Integer.toString(memoryi));}//'M+'的功能，将当前文本框里的数据和存储器中数据相加后，再存入存储器elseif (s == "M+" && clickable == true) {boolean isDot = false;for (int i = 0; i < text.getText().length(); i++)if ('.' == text.getText().charAt(i)) {isDot = true;break;}if (memoryi != 0) { //存储中是一个int型数if (isDot == false) //被加数是一个int型数memoryi += Integer.parseInt(text.getText());else { //被加数是一个double型数，则将int存储器中数传入double存储器与当前数相加，int存储器清零memoryd = memoryi + Double.parseDouble(text.getText());memoryi = 0;}}elsememoryd += Double.parseDouble(text.getText());}}elseif ('0' <= s.charAt(0) && s.charAt(0) <= '9' || s.equals(".")){ // text.setText("");if (start)text.setText(s);else text.setText(text.getText() + s);start = false;}else{ if (start){ if (s.equals("-")){ text.setText(s); start = false; }else op = s;}else{double x=Double.parseDouble(text.getText());calculate(x);op = s;start = true;}}}public void calculate(double n){ if (op.equals("+")) arg += n;else if (op.equals("-")) arg -= n;else if (op.equals("*")) arg *= n;else if (op.equals("/")) arg /= n;else if (op.equals("Mod")) arg %= n;else if (op.equals("=")) arg = n;text.setText("" + arg);}private double arg = 0;private String op = "=";private boolean start = true;public void itemStateChanged(ItemEvent e){}public static void main(String args[]){JFrame frame=new JFrame();jisuanqi myMenu=new jisuanqi();myMenu.init();myMenu.setVisible(true);//设置可见}}。

JAVA计算器论文

JAVA计算器论文摘要：本文介绍了JAVA计算器的设计和实现过程。

计算器是一种常见的工具，方便人们进行数学运算。

本文使用JAVA编程语言，采用面向对象的设计思想，实现了一个简单的计算器功能。

通过用户界面，用户可以输入数学表达式，并进行运算。

在实现过程中，使用了JAVA的图形用户界面库Swing，通过文本框和按钮等控件，实现了用户界面的设计。

通过对用户的输入进行解析，通过JAVA的计算功能，计算出结果。

在实验阶段，本文对计算器进行了一系列的测试，并找到了一些可能出现的问题并进行了改进，保证了计算器的正确性和稳定性。

实验结果表明，该计算器能够进行简单的数学运算，具有较高的精确性和用户友好性。

1.引言计算器是一种常见的工具，用于计算、解决各种数学问题。

计算器的出现大大方便了人们的生活和学习。

随着计算机的发展，计算器也逐渐发展成为计算机软件的一部分，通过软件实现计算器的功能，使计算器更易于使用和拓展。

本文使用JAVA编程语言，设计和实现了一个简单的计算器功能。

2.设计和实现2.1设计思路JAVA计算器的设计采用了面向对象的设计思想，将计算器的各个功能抽象成对象，并通过调用对象的方法来实现计算器的各种功能。

为了方便用户的使用，设计了一个用户界面，用户可以输入计算表达式，并通过点击按钮来进行运算。

JAVA的图形用户界面库Swing提供了丰富的组件和容器，本文使用了文本框、按钮等控件，来实现用户界面的设计。

2.2用户界面设计用户界面是用户和计算器之间的纽带，影响用户对计算器的使用体验。

本文实现了一个简单的用户界面，主要由一个文本框和一系列按钮组成。

用户可以在文本框中输入需要计算的表达式，并通过点击按钮来触发相应的计算操作。

2.3计算过程在用户输入表达式后，通过解析表达式，将其分解为操作数和操作符。

操作数可以是整数、小数或者其他表达式。

通过调用JAVA的计算功能，对操作数进行计算，并得到计算结果。

将结果显示在用户界面中。

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运算截图以下是源代码:package Calculator;/*** 计算器程序* 本程序有两个类(这两个类都在本文件中):* Calculate类负责纯数学运算* Calculator类负责图形界面显示**/importjava.awt.Font;importjava.awt.GridLayout;importjava.awt.event.ActionEvent;importjava.awt.event.ActionListener;importjava.awt.event.WindowAdapter;importjava.awt.event.WindowEvent;importjavax.swing.JButton;importjavax.swing.JDialog;importjavax.swing.JPanel;importjavax.swing.JScrollPane;importjavax.swing.JTextArea;@SuppressWarnings("serial")public class Calculator extends JDialog implements ActionListener {// 窗口组件privateJPanel panel;privateJTextArea text;JScrollPanescrollPane;privateJButton[] number;privateJButtonbt_Point,bt_Equal,bt_Plus,bt_Cut,bt_Multiply,bt_Division,bt_Pow,bt_Clear,bt_L,bt_R;//数学运算处理String inputStr = "";Calculate objCalculate=new Calculate();// "画"窗口public Calculator(){setTitle("计算器");setResizable(false);setSize(360, 400);Font font = new Font("宋体", Font.BOLD, 20);// 自定义字体text = new JTextArea();text.setEditable(false);text.setLineWrap(true);// 激活自动换行功能text.setWrapStyleWord(true);// 激活断行不断字功能text.setFont(font);scrollPane = new JScrollPane(text);scrollPane.setBounds(17, 20, 320, 100);panel = new JPanel();panel.setBounds(17, 140, 320, 220);panel.setLayout(new GridLayout(4, 5, 7, 7));number = new JButton[10];for (inti = 0; i< 10; ++i){number[i] = new JButton("" + i);number[i].setFont(font);number[i].addActionListener(this);}bt_L = new JButton("(");bt_L.setFont(font);bt_L.addActionListener(this);bt_R = new JButton(")");bt_R.setFont(font);bt_R.addActionListener(this);bt_Point = new JButton(".");bt_Point.setFont(font);bt_Point.addActionListener(this);bt_Equal = new JButton("=");bt_Equal.setFont(font);bt_Equal.addActionListener(this);bt_Plus = new JButton("+");bt_Plus.setFont(font);bt_Plus.addActionListener(this);bt_Cut = new JButton("-");bt_Cut.setFont(font);bt_Cut.addActionListener(this);bt_Multiply = new JButton("*");bt_Multiply.setFont(font);bt_Multiply.addActionListener(this);bt_Division = new JButton("/");bt_Division.setFont(font);bt_Division.addActionListener(this);bt_Pow = new JButton("^");bt_Pow.setFont(font);bt_Pow.addActionListener(this);bt_Clear = new JButton("C");bt_Clear.setFont(font);bt_Clear.addActionListener(this);for (inti = 7; i<= 9; ++i)panel.add(number[i]);panel.add(bt_L);panel.add(bt_R);for (inti = 4; i<= 6; ++i)panel.add(number[i]);panel.add(bt_Division);panel.add(bt_Multiply);for (inti = 1; i<= 3; ++i)panel.add(number[i]);panel.add(bt_Plus);panel.add(bt_Cut);panel.add(number[0]);panel.add(bt_Point);panel.add(bt_Equal);panel.add(bt_Pow);panel.add(bt_Clear);this.setLayout(null);this.add(scrollPane);this.add(panel);this.setResizable(false);this.setVisible(true);this.setDefaultCloseOperation(JDialog.DO_NOTHING_ON_CLOSE);this.addWindowListener(new WindowAdapter(){public void windowClosing(WindowEvent e){dispose();}});this.setLocation(500, 200);}//实现接口public void actionPerformed(ActionEvent e){JButtonbevent = (JButton) e.getSource();//获得输入的数学式子inputStr += bevent.getText();text.setText(inputStr);if (inputStr.endsWith("C")){inputStr = "";text.setText("0");}if (inputStr.endsWith("=")){ /* "="号触发运算*/text.setText(objCalculate.calculate(inputStr.substring(0,inputStr.length()-1)));inputStr="";}}// 主方法public static void main(String args[]){new Calculator();}}/** 数学计算类* 负责数学式子(不包含"="号)的数学运算,有运算优先级(括号最先,乘方次之,乘除再次之,加减最后等)* 思路:按运算优先级将数学式子步步化简* 数学式子用字符串存储* (测试通过)*/class Calculate{/** 服务:数学运算方法--对外接口,包括本地化数学式子格式、综合加减乘除乘方和括号等运算(功能可扩展)* 参数:要进行运算的数学式子* 返回:运算的结果或出错提示* (测试通过)*/public String calculate(String formula){String result="";formula=formula.replace(" ","");//去掉式子中的所有空格//用小括号替换大括号formula=formula.replace('{','(');formula=formula.replace('}',')');//用小括号替换中括号formula=formula.replace('[','(');formula=formula.replace(']',')');result=matchRemoveBracket(formula);if(result.startsWith("错误"))return result;result=basicArithmetic(result);System.out.println("原式:"+formula);System.out.println("运算结果:"+result);return result;}/** 服务:括号运算(包括括号匹对和去掉括号),从')'离式子开头最近的那一对括号开始* 参数:数学式子,规定括号前后紧挨着的只能是运算符或为空而不能是数字,如:* 87(35+3)2 错误* (-24)^2 正确* (23*34/(3*4)) 正确* 4/((-64)^3) 正确* 返回:去掉所有括号的式子或出错提示* (测试通过)*/private String matchRemoveBracket(String formula){System.out.println("括号运算开始!");System.out.println("括号运算:"+formula);if(formula.isEmpty())return "0";if(formula.startsWith("错误"))return formula;intleft,right;String number="";left=stIndexOf('(');right=formula.indexOf(')');while(left!=-1||right!=-1){if((left==-1&&right!=-1)||(left!=-1&&right==-1))return "错误--输入错误:括号不匹配!";if(left>right){left=formula.substring(0,right).lastIndexOf('(');if(left==-1)return "错误--输入错误:括号不匹配!";}if(left!=0){//规定括号前后紧挨着的只能是运算符或为空switch(formula.charAt(left-1)){case '+':case '-':case '*':case '/':case '^':case '(':break;default:return "错误--输入错误:括号前后不能紧挨着数字!";}}if(right!=formula.length()-1){switch(formula.charAt(right+1)){case '+':case '-':case '*':case '/':case '^':case ')':break;default:return "错误--输入错误:括号前后不能紧挨着数字!";}}//计算括号里面的式子,在此没有括号嵌套,"从')'离式子开头最近的那一对括号开始"保证了这一点number=basicArithmetic(formula.substring(left+1,right));if(number.startsWith("错误"))return number;if(number=="NaN")return "错误--运算错误!";if(Double.parseDouble(number)>=0)//基础运算结果非负数{if(right==formula.length()-1)formula=formula.substring(0,left)+number;else formula=formula.substring(0,left)+number+formula.substring(right+1);}else//基础运算结果为负数{if(right==formula.length()-1)formula=formula.substring(0,left)+"["+number+"]";elseformula=formula.substring(0,left)+"["+number+"]"+formula.substring(right+1);}if(formula.startsWith("错误"))return formula;System.out.println("括号运算:"+formula);left=stIndexOf('(');right=formula.indexOf(')');}System.out.println("括号运算结束!");return formula;}////////////////////////////////////////////基础运算/////////////////////////////////////////////** 服务:基础运算,包括加减乘除乘方运算* 参数:数学式子(不包含小括号)* 返回:基础运算结果或出错提示* (测试通过)*/private String basicArithmetic(String formula){String result="";result=sqrtPow(formula);if(result.startsWith("错误"))return result;result=multiplyDivide(result);if(result.startsWith("错误"))return result;result=additionSubtraction(result);return result;}/** 服务:乘方运算(开方运算可用等价的乘方运算替代,如:√4==4^0.5)* 参数:数学式子-- 有乘方,加减乘除的数学式子(不包含小括号)* 示例:* -345+93.4^2^0.5*64+32^2/2^2+9 正确参数* 87*(3+2)^2 错误参数* 返回:将化简乘方之后的式子或出错提示* (测试通过)*/private String sqrtPow(String formula){System.out.println("乘方运算");System.out.println("原式:"+formula);if(formula.startsWith("错误"))return formula;if(formula.startsWith("^")||formula.endsWith("^"))return "错误--输入错误!";//乘方运算for(inti=0;i<formula.length();++i){if(formula.charAt(i)=='^'){String number="",powN="";doublenum,pn;intai,bi;//获得乘方的底numberif(formula.charAt(i-1)==']')//负数{ai=formula.substring(0,i-1).lastIndexOf('[');if(ai==-1)return "错误--输入错误!";number=formula.substring(ai+1,i-1);if(ai>0)--ai;}else//正数{for(ai=i-1;ai>=0;--ai){if(formula.charAt(ai)=='*'||formula.charAt(ai)=='/'||formula.charAt(ai)=='+'||formula.charAt(ai)=='-'){number=formula.substring(ai+1,i);break;}}if(ai==-1){number=formula.substring(0,i);++ai;}}//获得乘方的幂powNif(formula.charAt(i+1)=='[')//负数{bi=formula.substring(i).indexOf(']');if(bi==-1)return "错误--输入错误!";bi+=i;powN=formula.substring(i+2,bi);++bi;}else{for(bi=i+1;bi<formula.length();++bi){if(formula.charAt(bi)=='+'||formula.charAt(bi)=='-'||formula.charAt(bi)=='*'||formula.charAt(bi)=='/'||formula.charAt(bi)=='^'){powN=formula.substring(i+1,bi);break;}}if(bi==formula.length())powN=formula.substring(i+1,bi);}System.out.println(number+" , "+powN);try{num=Double.parseDouble(number);pn=Double.parseDouble(powN);}catch(Exception ex){//错误包括:数字不能转换成double型等System.out.println("错误--输入错误!");return "错误--输入错误!";}try{number=""+Math.pow(num,pn);}catch(Exception ex){//错误包括:数字不能转换成double型等System.out.println("错误--运算错误!");return "错误--运算错误!";}if(number=="NaN")return "错误--运算错误!";if(Double.parseDouble(number)<0)number="["+number+"]";if(ai==0)formula=number+formula.substring(bi);else formula=formula.substring(0,ai+1)+number+formula.substring(bi);System.out.println("== >"+formula);i=ai+number.length()-1;}}//System.out.println("化简乘方之后的式子:\n"+formula);return formula;}/** 服务:乘除法运算* 参数:数学式子-- 只包含0-9、小数点和加减乘除号的的字符串(不包含小括号) * 示例:-345+93.4*64+32/2+* 返回:将化简乘除法之后的式子或出错提示* (测试通过)*/private String multiplyDivide(String formula){System.out.println("乘除运算");System.out.println("原式:"+formula);if(formula.isEmpty())return "0";if(formula.startsWith("错误"))return formula;//乘除号不能在式子的开头和结尾处if(formula.startsWith("*")||formula.startsWith("/")||formula.endsWith("*")||formula.endsWith("/"))return "错误--输入错误:乘除号位置不对!";String numberA=new String();String numberB=new String();double DA,DB;intai=0,bi=0;//遍历式子,优先进行乘除法运算for(inti=0;i<formula.length();++i){if(formula.charAt(i)=='*'||formula.charAt(i)=='/'){//获得被乘除数numberAif(formula.charAt(i-1)==']')//负数{ai=formula.substring(0,i-1).lastIndexOf('[');if(ai==-1)return "错误--输入错误!";numberA=formula.substring(ai+1,i-1);if(ai>0)--ai;}else{for(ai=i-1;ai>0;--ai){if(formula.charAt(ai)=='*'||formula.charAt(ai)=='/'||formula.charAt(ai)=='+'||formula.charAt(ai)=='-') {numberA=formula.substring(ai+1,i);break;}}if(ai==0)numberA=formula.substring(ai,i);}//获得乘除数numberBif(formula.charAt(i+1)=='[')//负数{bi=formula.substring(i).indexOf(']');if(bi==-1)return "错误--输入错误!";bi+=i;numberB=formula.substring(i+2,bi);++bi;}else{for(bi=i+1;bi<formula.length();++bi){if(formula.charAt(bi)=='*'||formula.charAt(bi)=='/'||formula.charAt(bi)=='+'||formula.charAt(bi)=='-') {numberB=formula.substring(i+1,bi);break;}}if(bi==formula.length())numberB=formula.substring(i+1,bi);}System.out.println(numberA+" , "+numberB);try{DA=Double.parseDouble(numberA);DB=Double.parseDouble(numberB);}catch(Exception ex){//错误包括:乘除号两边为空,数字不能转换成double型等System.out.println("错误--输入错误!");return "错误--输入错误!";}//乘法运算if(formula.charAt(i)=='*'){//在此,numberA暂时充当结果存放容器numberA=""+(DA*DB);}//除法运算else {//除数不能为0if(DB==0)return "错误--输入错误:除数不能为零";numberA=""+(DA/DB);}if(Double.parseDouble(numberA)<0)numberA="["+numberA+"]";if(ai==0)formula=numberA+formula.substring(bi);else formula=formula.substring(0,ai+1)+numberA+formula.substring(bi);System.out.println("== >"+formula);i=ai+numberA.length()-1;}}//System.out.println("化简乘除法之后的式子:\n"+formula);return formula;}/** 服务:加减法运算,此算法只包含加减的数学运算,负数(中括号括起来)可以直接参与运算* 参数:数学式子-- 只包含0-9、小数点和加减号的的字符串(可以包含中括号[]但不包含小括号())* 示例:93-39+92* 返回:运算结果或出错提示* (测试通过)*/private String additionSubtraction(String formula){System.out.println("加减运算");System.out.println("原式:"+formula);if(formula.isEmpty())return "0";if(formula.startsWith("错误"))return formula;if(formula.startsWith("]")||formula.endsWith("["))return "错误--输入错误!";String numberA=new String();String numberB=new String();double DA,DB;int bi=0;//统一式子格式<一>:式子以加减号结束,末尾添加上0if(formula.endsWith("+")||formula.endsWith("-"))formula=formula+0;//统一式子格式<二>:式子以加减号开始,开头添加上0if(formula.startsWith("+")||formula.startsWith("-"))formula=0+formula;//统一式子格式<三>:式子以[]开始,开头添加上"0+"if(formula.startsWith("["))formula="0+"+formula;//遍历式子,从左到右进行加减运算(式子到此只有加减运算)for(inti=0;i<formula.length();++i){if(formula.charAt(i)=='+'||formula.charAt(i)=='-'){//获得被加减数numberAnumberA=formula.substring(0,i);//获得加减数numberBif(formula.charAt(i+1)=='[')//负数{bi=formula.indexOf(']');if(bi==-1)return "错误--输入错误!";numberB=formula.substring(i+2,bi);++bi;}else{for(bi=i+1;bi<formula.length();++bi){if(formula.charAt(bi)=='+'||formula.charAt(bi)=='-'){numberB=formula.substring(i+1,bi);break;}}if(bi==formula.length())numberB=formula.substring(i+1,bi);}System.out.println(numberA+" , "+numberB);//加减号两边可以为空if(numberB.isEmpty())numberB="0";try{DA=Double.parseDouble(numberA);DB=Double.parseDouble(numberB);}catch(Exception ex){//错误包括:数字不能转换成double型等System.out.println("错误--输入错误!");return "错误--输入错误!";}//加法运算if(formula.charAt(i)=='+'){//在此,numberA暂时充当结果存放容器numberA=""+(DA+DB);}//减法运算else {numberA=""+(DA-DB);}formula=numberA+formula.substring(bi);System.out.println("== >"+formula);i=numberA.length()-1;}}return formula;}}。

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