标准计算器java代码 标准计算器java代码怎么用

java计算器代码

import java.awt.*;

创新互联致力于互联网品牌建设与网络营销，包括做网站、成都网站设计、SEO优化、网络推广、整站优化营销策划推广、电子商务、移动互联网营销等。创新互联为不同类型的客户提供良好的互联网应用定制及解决方案，创新互联核心团队十载专注互联网开发，积累了丰富的网站经验，为广大企业客户提供一站式企业网站建设服务，在网站建设行业内树立了良好口碑。

import java.awt.event.*;

public class lvhaiya{

int tmp,sum,sum1,sum2=1,sum3=1;

String a,b,c,d;String s="";

Frame f=new Frame("计算器");

private String[]name={

"0","1","2","3","4","5","6","7","8","9","+","-","*","/","=","空格"

};

public Button[] button=new Button[name.length];

TextField t=new TextField("",30);

Panel p=new Panel();

Panel p1=new Panel();

Color color=new Color(100,170,90);

public lvhaiya(){

p1.setLayout(new GridLayout(5,5));

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

button[i]=new Button(name[i]);

p1.add(button[i]);

}

p.setLayout(new FlowLayout(FlowLayout.LEFT));

p.setBackground(color);

p.add(t);

f.add(p,BorderLayout.NORTH);

f.add(p1,BorderLayout.SOUTH);

f.pack();

f.setVisible(true);

f.addWindowListener( new WindowClose());

t.setText("0.");

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

button[i].addActionListener(new ButtonEventl());

}

}

public static void main(String[]args){

new lvhaiya();

}

class WindowClose extends WindowAdapter{

public void windouClosing(WindowEvent e){

System.exit(0);

}

}

class ButtonEventl implements ActionListener{

public void actionPerformed(ActionEvent e)throws ArithmeticException{

String command=e.getActionCommand();

if(command.equals("+")){

sum=Integer.parseInt(t.getText())+sum;

t.setText(String.valueOf(sum));

a=t.getText();

s="";

}

else if(command.equals("-")){

sum1=Integer.parseInt(t.getText());

b=t.getText();

s="";

}

else if(command.equals("*")){

sum2=Integer.parseInt(t.getText())*sum2;

t.setText(String.valueOf(sum2));

c=t.getText();

s="";

}

else if(command.equals("/")){

sum3=Integer.parseInt(t.getText());

d=t.getText();

s="";

}

else if(command.equals("=")){

if(a!=null){

t.setText(String.valueOf(sum+tmp));

}

if(b!=null){

t.setText(String.valueOf(sum1-tmp));

}

if(c!=null){

t.setText(String.valueOf(sum2*tmp));

}

try{

if(d!=null){

t.setText(String.valueOf(sum3/tmp));

}

}

catch(ArithmeticException a){

t.setText("除数不能为零");

}

}

else if(command.equals("空格")){

sum=0;

a=null;

b=null;

c=null;

d=null;

sum1=0;

sum2=1;

sum3=1;

tmp=0;

t.setText("0");

s="";

}

else{

s=s+command;

t.setText(s);

tmp=Integer.parseInt(s);

}

}

}

}

//按钮可以自己美化一下 希望可以帮到你

java 计算器代码

import javax.swing.*;

import javax.swing.border.Border;

import java.awt.*;

import java.awt.event.ActionListener;

import java.awt.event.ActionEvent;

import java.math.BigDecimal;

import java.math.RoundingMode;

import java.util.HashMap;

/**

* 我的计算器。Cheshi 继承于 JFrame，是计算器的界面

c*/

public class Cheshi extends JFrame {

private Border border = BorderFactory.createEmptyBorder(5, 5, 5, 5);

private JTextField textbox = new JTextField("0");

private CalculatorCore core = new CalculatorCore();

private ActionListener listener = new ActionListener() {

public void actionPerformed(ActionEvent e) {

JButton b = (JButton) e.getSource();

String label = b.getText();

String result = core.process(label);

textbox.setText(result);

}

};

public Cheshi(String title) throws HeadlessException {

super(title); // 调用父类构造方法

setupFrame(); // 调整窗体属性

setupControls(); // 创建控件

}

private void setupControls() {

setupDisplayPanel(); // 创建文本面板

setupButtonsPanel(); // 创建按钮面板

}

// 创建按钮面板并添加按钮

private void setupButtonsPanel() {

JPanel panel = new JPanel();

panel.setBorder(border);

panel.setLayout(new GridLayout(4, 5, 3, 3));

createButtons(panel, new String[]{

"7", "8", "9", "+", "C",

"4", "5", "6", "-", "CE",

"1", "2", "3", "*", "", // 空字符串表示这个位置没有按钮

"0", ".", "=", "/", ""

});

this.add(panel, BorderLayout.CENTER);

}

/**

* 在指定的面板上创建按钮

*

* @param panel 要创建按钮的面板

* @param labels 按钮文字

*/

private void createButtons(JPanel panel, String[] labels) {

for (String label : labels) {

// 如果 label 为空，则表示创建一个空面板。否则创建一个按钮。

if (label.equals("")) {

panel.add(new JPanel());

} else {

JButton b = new JButton(label);

b.addActionListener(listener); // 为按钮添加侦听器

panel.add(b);

}

}

}

// 设置显示面板，用一个文本框来作为计算器的显示部分。

private void setupDisplayPanel() {

JPanel panel = new JPanel();

panel.setLayout(new BorderLayout());

panel.setBorder(border);

setupTextbox();

panel.add(textbox, BorderLayout.CENTER);

this.add(panel, BorderLayout.NORTH);

}

// 调整文本框

private void setupTextbox() {

textbox.setHorizontalAlignment(JTextField.RIGHT); // 文本右对齐

textbox.setEditable(false); // 文本框只读

textbox.setBackground(Color.white); // 文本框背景色为白色

}

// 调整窗体

private void setupFrame() {

this.setDefaultCloseOperation(EXIT_ON_CLOSE); // 当窗体关闭时程序结束

this.setLocation(100, 50); // 设置窗体显示在桌面上的位置

this.setSize(300, 200); // 设置窗体大小

this.setResizable(false); // 窗体大小固定

}

// 程序入口

public static void main(String[] args) throws Exception {

UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());

Cheshi frame = new Cheshi("我的计算器");

frame.setVisible(true); // 在桌面上显示窗体

}

}

/**

* 计算器核心逻辑。这个逻辑只能处理 1~2 个数的运算。

*/

class CalculatorCore {

private String displayText = "0"; // 要显示的文本

boolean reset = true;

private BigDecimal number1, number2;

private String operator;

private HashMapString, Operator operators = new HashMapString, Operator();

private HashMapString, Processor processors = new HashMapString, Processor();

CalculatorCore() {

setupOperators();

setupProcessors();

}

// 为每种命令添加处理方式

private void setupProcessors() {

processors.put("[0-9]", new Processor() {

public void calculate(String command) {

numberClicked(command);

}

});

processors.put("\\.", new Processor() {

public void calculate(String command) {

dotClicked();

}

});

processors.put("=", new Processor() {

public void calculate(String command) {

equalsClicked();

}

});

processors.put("[+\\-*/]", new Processor() {

public void calculate(String command) {

operatorClicked(command);

}

});

processors.put("C", new Processor() {

public void calculate(String command) {

clearClicked();

}

});

processors.put("CE", new Processor() {

public void calculate(String command) {

clearErrorClicked();

}

});

}

// 为每种 operator 添加处理方式

private void setupOperators() {

operators.put("+", new Operator() {

public BigDecimal process(BigDecimal number1, BigDecimal number2) {

return number1.add(number2);

}

});

operators.put("-", new Operator() {

public BigDecimal process(BigDecimal number1, BigDecimal number2) {

return number1.subtract(number2);

}

});

operators.put("*", new Operator() {

public BigDecimal process(BigDecimal number1, BigDecimal number2) {

return number1.multiply(number2);

}

});

operators.put("/", new Operator() {

public BigDecimal process(BigDecimal number1, BigDecimal number2) {

return number1.divide(number2, 30, RoundingMode.HALF_UP);

}

});

}

// 根据命令处理。这里的命令实际上就是按钮文本。

public String process(String command) {

for (String pattern : processors.keySet()) {

if (command.matches(pattern)) {

processors.get(pattern).calculate(command);

break;

}

}

return displayText;

}

// 当按下 CE 时

private void clearErrorClicked() {

if (operator == null) {

number1 = null;

} else {

number2 = null;

}

displayText = "0";

reset = true;

}

// 当按下 C 时，将计算器置为初始状态。

private void clearClicked() {

number1 = null;

number2 = null;

operator = null;

displayText = "0";

reset = true;

}

// 当按下 = 时

private void equalsClicked() {

calculateResult();

number1 = null;

number2 = null;

operator = null;

reset = true;

}

// 计算结果

private void calculateResult() {

number2 = new BigDecimal(displayText);

Operator oper = operators.get(operator);

if (oper != null) {

BigDecimal result = oper.process(number1, number2);

displayText = result.toString();

}

}

// 当按下 +-*/ 时（这里也可以扩展成其他中间操作符）

private void operatorClicked(String command) {

if (operator != null) {

calculateResult();

}

number1 = new BigDecimal(displayText);

operator = command;

reset = true;

}

// 当按下 . 时

private void dotClicked() {

if (displayText.indexOf(".") == -1) {

displayText += ".";

} else if (reset) {

displayText = "0.";

}

reset = false;

}

// 当按下 0-9 时

private void numberClicked(String command) {

if (reset) {

displayText = command;

} else {

displayText += command;

}

reset = false;

}

// 运算符处理接口

interface Operator {

BigDecimal process(BigDecimal number1, BigDecimal number2);

}

// 按钮处理接口

interface Processor {

void calculate(String command);

}

}

求计算器Java代码。。。

import java.awt.*;

import javax.swing.*;

import java.awt.event.*;

import javax.swing.event.*;

class JPanelEa1 extends JFrame implements MenuListener,ActionListener

{

JPanel mainp,p1,p2,p3,p4;

JTextField jt1;

JMenuItem mnuCopy;

JMenuItem mnuPaste;

JButton bM;

boolean isDouble = false;// 是否为实数

int opFlag = -1;

static double t1 = 0, t2 = 0, t3 = 0, result = 0;

static int opflag1 = -1, opflag2 = -1, flag = 0, resflag = 1;

int preOp, currentOp = 0;// 标准位

double op1 = 0, op2 = 0;// 操作数

double n3;

StringBuffer buf = new StringBuffer(20);

StringBuffer copyBoard = new StringBuffer(20);// 剪贴板

StringBuffer memory = new StringBuffer(20);// M系列

StringBuffer str = new StringBuffer();

public JPanelEa1()

{

p1=new JPanel();

p1.setLayout(new GridLayout(2,1,10,10));

JMenuBar mnuNotepad=new JMenuBar();

JMenu mnuEdit=new JMenu("编辑(E)");

mnuEdit.setMnemonic(KeyEvent.VK_E);

JMenu mnuCheck=new JMenu("查看(V)");

mnuCheck.setMnemonic(KeyEvent.VK_V);

JMenu mnuHelp=new JMenu("帮助(H)");

mnuCopy=new JMenuItem("复制(C)");

mnuPaste=new JMenuItem("粘贴(P)");

JMenuItem mnuVisit=new JMenuItem("查看帮助(V)");

JMenuItem mnuAbout=new JMenuItem("关于计算器(A)");

JSeparator sep=new JSeparator();

jt1=new JTextField("0.");

jt1.setEnabled(false);

jt1.setHorizontalAlignment(JTextField.RIGHT);

mnuEdit.addMenuListener(this);

mnuCheck.addMenuListener(this);

mnuHelp.addMenuListener(this);

mnuCopy.addActionListener(this);

mnuPaste.addActionListener(this);

mnuVisit.addActionListener(this);

mnuAbout.addActionListener(this);

mnuNotepad.add(mnuEdit);

mnuNotepad.add(mnuCheck);

mnuNotepad.add(mnuHelp);

mnuEdit.add(mnuCopy);

mnuEdit.add(mnuPaste);

mnuEdit.add(sep);

mnuHelp.add(mnuVisit);

mnuHelp.add(sep);

mnuHelp.add(mnuAbout);

p1.add(mnuNotepad);

p1.add(jt1);

p2=new JPanel();

p2.setLayout(new FlowLayout(FlowLayout.CENTER));

bM = new JButton(" ");

bM.setEnabled(false);

p2.add(bM);

Button b25=new Button("Backspace");

b25.addActionListener(this);

Button b26=new Button("CE");

b26.addActionListener(this);

Button b27=new Button("C");

b27.addActionListener(this);

p2.add(b25);

p2.add(b26);

p2.add(b27);

p3=new JPanel();

p3.setLayout(new GridLayout(4,6));

Button button1=new Button("MC");

button1.addActionListener(this);

Button button2=new Button("7");

button2.addActionListener(this);

Button button3=new Button("8");

button3.addActionListener(this);

Button button4=new Button("9");

button4.addActionListener(this);

Button button5=new Button("/");

button5.addActionListener(this);

Button button6=new Button("sqrt");

button6.addActionListener(this);

Button button7=new Button("MR");

button7.addActionListener(this);

Button button8=new Button("4");

button8.addActionListener(this);

Button button9=new Button("5");

button9.addActionListener(this);

Button button10=new Button("6");

button10.addActionListener(this);

Button button11=new Button("*");

button11.addActionListener(this);

Button button12=new Button("%");

button12.addActionListener(this);

Button button13=new Button("MS");

button13.addActionListener(this);

Button button14=new Button("1");

button14.addActionListener(this);

Button button15=new Button("2");

button15.addActionListener(this);

Button button16=new Button("3");

button16.addActionListener(this);

Button button17=new Button("-");

button17.addActionListener(this);

Button button18=new Button("1/x");

button18.addActionListener(this);

Button button19=new Button("M+");

button19.addActionListener(this);

Button button20=new Button("0");

button20.addActionListener(this);

Button button21=new Button("+/-");

button21.addActionListener(this);

Button button22=new Button(".");

button22.addActionListener(this);

Button button23=new Button("+");

button23.addActionListener(this);

Button button24=new Button("=");

button24.addActionListener(this);

p3.add(button1);p3.add(button2);

p3.add(button3);p3.add(button4);

p3.add(button5);p3.add(button6);

p3.add(button7);p3.add(button8);

p3.add(button9);p3.add(button10);

p3.add(button11);p3.add(button12);

p3.add(button13);p3.add(button14);

p3.add(button15);p3.add(button16);

p3.add(button17);p3.add(button18);

p3.add(button19);p3.add(button20);

p3.add(button21);p3.add(button22);

p3.add(button23);p3.add(button24);

setSize(250,150);

mainp=new JPanel();

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

mainp.add(p1);

mainp.add(p2);

mainp.add(p3);

setContentPane(mainp);

setTitle("计算器");

setSize(300,300);

setVisible(true);

setDefaultCloseOperation(EXIT_ON_CLOSE);

}

public void actionPerformed(ActionEvent e)

{

String s= e.getActionCommand();

if (s.equals("复制(C)")) {

String temp = jt1.getText().trim();

copyBoard.replace(0, copyBoard.length(), temp);

mnuPaste.setEnabled(true);

} else if (s.equals("粘贴(p)")) {

jt1.setText(copyBoard.toString());

} else if (s.equals("CE")) {

// 如果是CE则清除文本框

jt1.setText("0.");

} else if (s.equals("Backspace")) {

if (!jt1.getText().trim().equals("0.")) {

// 如果文本框中有内容

if (str.length() != 1 str.length() != 0) {

jt1.setText(str.delete(str.length() - 1, str.length())

.toString());

} else {

jt1.setText("0.");

str.setLength(0);

}

}

op2 = Double.parseDouble(jt1.getText().trim());

} else if (s.equals("C")) {

// 如果是C删除当前计算

jt1.setText("0.");

op1 = op2 = 0;

str.replace(0, str.length(), " ");

preOp = currentOp = 0;

} else if (s.equals("MC")) {

// 如果是MC则清除缓冲区

String temp = "";

memory.replace(0, memory.length(), temp);

bM.setText(" ");

} else if (s.equals("MR")) {

// 如果按键为MR则恢复缓冲区的数到文本框

jt1.setText(memory.toString());

} else if (s.equals("MS")) {

// 如果按键为MS则将文本框的数存入缓冲区

String s1 = jt1.getText().trim();

memory.replace(0, memory.length(), s1);

bM.setText("M");

} else if (s.equals("M+")) {

// 如果按键为MS则将文本框值与缓冲区的数相加但不显示结果

String temp1 = jt1.getText().trim();

double dtemp = Double.parseDouble(temp1);

String temp2 = memory.toString();

dtemp += Double.parseDouble(temp2);

temp1 = String.valueOf(dtemp);

memory.replace(0, memory.length(), temp1);

} else if (s.equals("1/x")) {

// 如果按键为1/x则将文本框中的数据为它的倒数

String temp = jt1.getText().trim();

double dtemp = Double.parseDouble(temp);

jt1.setText("" + 1 / dtemp);

} else if (s.equals("sqrt")) {

// 如果按键为sqrt则将文本框中的内容求平方根

String temp = jt1.getText().trim();

double dtemp = Double.parseDouble(temp);

jt1.setText("" + Math.sqrt(dtemp));

} else if (s.equals("+")) {

str.setLength(0);

if (currentOp == 0) {

preOp = currentOp = 1;

op2 = 0;

jt1.setText("" + op1);

} else {

currentOp = preOp;

preOp = 1;

switch (currentOp) {

case 1:

op1 += op2;

jt1.setText("" + op1);

break;

case 2:

op1 -= op2;

jt1.setText("" + op1);

break;

case 3:

op1 *= op2;

jt1.setText("" + op1);

break;

case 4:

op1 /= op2;

jt1.setText("" + op1);

break;

}

}

} else if (s.equals("-")) {

str.setLength(0);

if (currentOp == 0) {

preOp = currentOp = 2;// op1=op2;op2=0;

jt1.setText("" + op1);

} else {

currentOp = preOp;

preOp = 2;

switch (currentOp) {

case 1:

op1 = op1 + op2;

jt1.setText("" + op1);

break;

case 2:

op1 = op1 - op2;

jt1.setText("" + op1);

break;

case 3:

op1 = op1 * op2;

jt1.setText("" + op1);

break;

case 4:

op1 = op1 / op2;

jt1.setText("" + op1);

break;

}

}

} else if (s.equals("*"))// *

{

str.setLength(0);

if (currentOp == 0) {

preOp = currentOp = 3;// op1=op2;op2=1;

jt1.setText("" + op1);// op1=op2;

} else {

currentOp = preOp;

preOp = 3;

switch (currentOp) {

case 1:

op1 = op1 + op2;

jt1.setText("" + op1);

break;

case 2:

op1 = op1 - op2;

jt1.setText("" + op1);

break;

case 3:

op1 = op1 * op2;

jt1.setText("" + op1);

break;

case 4:

op1 = op1 / op2;

jt1.setText("" + op1);

break;

}

}

} else if (s.equals("/"))// /

{

str.setLength(0);

if (currentOp == 0) {

preOp = currentOp = 4;// op2=1;

jt1.setText("" + op1);// op1=op2;

} else {

currentOp = preOp;

preOp = 4;

switch (currentOp) {

case 1:

op1 = op1 + op2;

jt1.setText("" + op1);

break;

case 2:

op1 = op1 - op2;

jt1.setText("" + op1);

break;

case 3:

op1 = op1 * op2;

jt1.setText("" + op1);

break;

case 4:

op1 = op1 / op2;

jt1.setText("" + op1);

break;

}

}

} else if (s.equals("="))// =

{

if (currentOp == 0) {

str.setLength(0);

jt1.setText("" + op2);

} else {

str.setLength(0);

currentOp = preOp;

switch (currentOp) {

case 1:

op1 = op1 + op2;

jt1.setText("" + op1);

break;

case 2:

op1 = op1 - op2;

jt1.setText("" + op1);

break;

case 3:

op1 = op1 * op2;

jt1.setText("" + op1);

break;

case 4:

op1 = op1 / op2;

jt1.setText("" + op1);

break;

}

currentOp = 0;

op2 = 0;

}

} else if (s.equals(".")) {

isDouble = true;

if (jt1.getText().trim().indexOf('.') != -1)

;

else {

if (jt1.getText().trim().equals("0")) {

str.setLength(0);

jt1.setText((str.append("0" + s)).toString());

}

// else

// if(jt1.getText().trim().equals("")){}//如果初时显示为空则不做任何操作

else {

jt1.setText((str.append(s)).toString());

}

}

} else if (s.equals("0"))// 如果选择的是"0"这个数字键

{

if (jt1.getText().trim().equals("0.")) {

} else {

jt1.setText(str.append(s).toString());

op2 = Double.parseDouble(jt1.getText().trim());

}

} else {

jt1.setText(str.append(s).toString());

op2 = Double.parseDouble(jt1.getText().trim());

if (currentOp == 0)

op1 = op2;

}

}

public static void main(String args[])

{

JPanelEa1 g=new JPanelEa1();

}

@Override

public void menuSelected(MenuEvent e) {

// TODO Auto-generated method stub

}

@Override

public void menuDeselected(MenuEvent e) {

// TODO Auto-generated method stub

}

@Override

public void menuCanceled(MenuEvent e) {

// TODO Auto-generated method stub

}

}

java编一个计算器的代码

界面漂亮堪比系统自带计算器，功能完美加减乘除开平方等等全部具备，还有清零按钮，小数点的使用，连加连乘功能完全参考系统官方计算器经过长期调试改进而成，马上拷贝代码拿去试试看吧，绝不后悔！

代码如下：

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import java.util.*;

public class Counter {

public static void main(String[] args) {

CounterFrame frame = new CounterFrame();

frame.show();

}

}

class CounterFrame extends JFrame {

public CounterFrame() {

JMenuBar menuBar = new JMenuBar();

JMenu menuFile = new JMenu();

JMenu menuFile1 = new JMenu();

JMenu menuFile2 = new JMenu();

JMenu menuFile3 = new JMenu();

JMenuItem menuFileExit = new JMenuItem();

menuFile.setText("文件");

menuFile1.setText("编辑");

menuFile2.setText("查看");

menuFile3.setText("帮助");

menuFileExit.setText("退出");

menuFileExit.addActionListener

(

new ActionListener() {

public void actionPerformed(ActionEvent e) {

CounterFrame.this.windowClosed();

}

}

);

menuFile.add(menuFileExit);

menuBar.add(menuFile);

menuBar.add(menuFile1);

menuBar.add(menuFile2);

menuBar.add(menuFile3);

setTitle("计算器");

setJMenuBar(menuBar);

setSize(new Dimension(400, 280));

this.getContentPane().add(new Allpanel());

this.addWindowListener

(

new WindowAdapter() {

public void windowClosing(WindowEvent e) {

CounterFrame.this.windowClosed();

}

}

);

}

protected void windowClosed() {

System.exit(0);

}

}

class Tool {

public static Tool instance;

private JTextField field;

private Tool() {

this.field=new JTextField(30);

this.field.setHorizontalAlignment(JTextField.RIGHT);

}

public static Tool getinstance()

{

if(instance==null)

{

instance=new Tool();

}

return instance;

}

public JTextField getfield()

{

return (this.field);

}

}

class Allpanel extends JPanel {

public Allpanel() {

this.setLayout(new BorderLayout(0,7));

Northpanel np=new Northpanel();

Centerpanel cp=new Centerpanel();

this.add(np,BorderLayout.NORTH);

this.add(cp,BorderLayout.CENTER);

}

}

class Centercenter extends JPanel {

static Vector Vec=new Vector();

static Vector vc=new Vector();

static Vector vc1=new Vector();

static Vector vc2=new Vector();

static Vector vc3=new Vector();

static String begin="yes";

static double add;

static double jq;

static double cs;

static double cq;

static double dy;

static String jg;

static String what;

static double tool=0;

static String to="yes";

/**

* Method Centercenter

*

*

*/

public Centercenter() {

// TODO: Add your code here

final JTextField text=Tool.getinstance().getfield();

this.setLayout(new GridLayout(4,5,3,3));

String arg[] ={"7","8","9","/","sqrt","4","5","6","*","%","1","2","3","-","1/x","0","+/-",".","+","="};

for(int i=0;i20;i++)

{

final JButton b=new JButton(arg[i]);

//this.add(new JButton(arg[i]));

this.add(b);

if(i==0||i==1||i==2||i==5||i==6||i==7||i==10||i==11||i==12||i==15)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String mark=b.getText();

String ma=text.getText();

if(vc3.contains("v3"))

{

text.setText("0."+mark);

vc3.clear();

}

else if(vc.contains("a"))

{

if(vc2.contains("v2"))

{

text.setText("0."+mark);

vc.clear();

vc2.clear();

}

else

{

text.setText(mark);

vc.clear();

Vec.clear();

Vec.add(mark);

}

}

else

{

text.setText(ma.trim()+mark);

Vec.add(mark);

}

begin="no";

to="yes";

}

});

}

if(i==17)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String mar=b.getText();

String m=text.getText();

if("yes".equals(begin))

{

vc3.add("v3");

}

if(vc1.contains("v1"))

{

vc2.add("v2");

vc1.clear();

}

if(!Vec.contains(".")!vc.contains("a"))

{

text.setText(m.trim()+mar);

Vec.add(".");

}

}

});

}

if(i==18)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

add=Double.parseDouble(ma);

if(what==null)

{

tool=add;

what="add";

}

else

{

tool=tool+add;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="+";

}

});

}

if(i==13)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

jq=Double.parseDouble(ma);

if(what==null)

{

tool=jq;

what="jq";

}

else

{

tool=tool-jq;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="-";

}

});

}

if(i==3)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

cq=Double.parseDouble(ma);

if(what==null)

{

tool=cq;

what="cq";

}

else

{

tool=tool/cq;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="/";

}

});

}

if(i==4)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

cq=Double.parseDouble(ma);

text.setText(String.valueOf(Math.sqrt(cq)));

}

});

}

if(i==8)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

cs=Double.parseDouble(ma);

if(what==null)

{

tool=cs;

what="cs";

}

else

{

tool=tool*cs;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="*";

}

});

}

if(i==19)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

dy=Double.parseDouble(ma);

if(what=="add")

{

jg=String.valueOf((tool+dy));

}

if(what=="jq")

{

jg=String.valueOf((tool-dy));

}

if(what=="cs")

{

jg=String.valueOf((tool*dy));

}

if(what=="cq")

{

jg=String.valueOf((tool/dy));

}

if(what==null)

{

if(to=="+")

{

tool=add;

jg=String.valueOf(tool+dy);

}

else if(to=="-")

{

tool=jq;

jg=String.valueOf(dy-tool);

}

else if(to=="*")

{

tool=cs;

jg=String.valueOf(dy*tool);

}

else if(to=="/")

{

tool=cq;

jg=String.valueOf(dy/tool);

}

else

{

jg=String.valueOf(dy);

}

}

text.setText(jg);

Vec.clear();

Vec.add(".");

vc.add("a");

vc1.add("v1");

what=null;

tool=0;

}

});

}

}

}

}

class Centernorth extends JPanel {

public Centernorth() {

final JTextField text=Tool.getinstance().getfield();

JButton jb1=new JButton("Backspace");

JButton jb2=new JButton(" CE ");

JButton jb3=new JButton(" C ");

this.add(jb1);

this.add(jb2);

this.add(jb3);

jb1.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e)

{

String back=Tool.getinstance().getfield().getText();

text.setText(backmethod(back));

Centercenter.Vec.remove(Centercenter.Vec.size()-1);

}

});

jb3.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e)

{

text.setText("0.");

Centercenter.Vec.clear();

Centercenter.Vec.add(".");

Centercenter.vc.add("a");

Centercenter.begin="yes";

Centercenter.vc1.clear();

Centercenter.what=null;

Centercenter.tool=0;

}

});

}

public String backmethod(String str)

{

return str.substring(0,str.length()-1);

}

}

class Centerpanel extends JPanel {

public Centerpanel() {

this.setLayout(new BorderLayout(8,7));

Centernorth cn=new Centernorth();

Centercenter cc=new Centercenter();

Centerwest cw=new Centerwest();

this.add(cn,BorderLayout.NORTH);

this.add(cc,BorderLayout.CENTER);

this.add(cw,BorderLayout.WEST);

}

}

class Centerwest extends JPanel {

public Centerwest() {

this.setLayout(new GridLayout(4,1,3,3));

this.add(new JButton("MC"));

this.add(new JButton("MR"));

this.add(new JButton("MS"));

this.add(new JButton("M+"));

}

}

class Northpanel extends JPanel {

private JTextField tf;

public Northpanel() {

tf=Tool.getinstance().getfield();

this.add(tf);

}

}

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

=============《按你要求特意后改过的最简单功能的代码如下》========================

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

import java.util.*;

public class Counter2 {

public static void main(String[] args) {

CounterFrame frame = new CounterFrame();

frame.show();

}

}

class CounterFrame extends JFrame {

public CounterFrame() {

setTitle("计算器");

setSize(new Dimension(400, 280));

this.getContentPane().add(new Allpanel());

this.addWindowListener

(

new WindowAdapter() {

public void windowClosing(WindowEvent e) {

CounterFrame.this.windowClosed();

}

}

);

}

protected void windowClosed() {

System.exit(0);

}

}

class Tool {

public static Tool instance;

private JTextField field;

private Tool() {

this.field=new JTextField(30);

this.field.setHorizontalAlignment(JTextField.RIGHT);

}

public static Tool getinstance()

{

if(instance==null)

{

instance=new Tool();

}

return instance;

}

public JTextField getfield()

{

return (this.field);

}

}

class Allpanel extends JPanel {

public Allpanel() {

this.setLayout(new BorderLayout(0,7));

Northpanel np=new Northpanel();

Centerpanel cp=new Centerpanel();

this.add(np,BorderLayout.NORTH);

this.add(cp,BorderLayout.CENTER);

}

}

class Centercenter extends JPanel {

static Vector Vec=new Vector();

static Vector vc=new Vector();

static Vector vc1=new Vector();

static Vector vc2=new Vector();

static Vector vc3=new Vector();

static String begin="yes";

static double add;

static double jq;

static double cs;

static double cq;

static double dy;

static String jg;

static String what;

static double tool=0;

static String to="yes";

/**

* Method Centercenter

*

*

*/

public Centercenter() {

// TODO: Add your code here

final JTextField text=Tool.getinstance().getfield();

this.setLayout(new GridLayout(4,5,3,3));

String arg[] ={"7","8","9","/","4","5","6","*","1","2","3","-","0","=",".","+"};

for(int i=0;i16;i++)

{

final JButton b=new JButton(arg[i]);

//this.add(new JButton(arg[i]));

this.add(b);

if(i==0||i==1||i==2||i==4||i==5||i==6||i==8||i==9||i==10||i==12)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String mark=b.getText();

String ma=text.getText();

if(vc3.contains("v3"))

{

text.setText("0."+mark);

vc3.clear();

}

else if(vc.contains("a"))

{

if(vc2.contains("v2"))

{

text.setText("0."+mark);

vc.clear();

vc2.clear();

}

else

{

text.setText(mark);

vc.clear();

Vec.clear();

Vec.add(mark);

}

}

else

{

text.setText(ma.trim()+mark);

Vec.add(mark);

}

begin="no";

to="yes";

}

});

}

if(i==14)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String mar=b.getText();

String m=text.getText();

if("yes".equals(begin))

{

vc3.add("v3");

}

if(vc1.contains("v1"))

{

vc2.add("v2");

vc1.clear();

}

if(!Vec.contains(".")!vc.contains("a"))

{

text.setText(m.trim()+mar);

Vec.add(".");

}

}

});

}

if(i==15)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

add=Double.parseDouble(ma);

if(what==null)

{

tool=add;

what="add";

}

else

{

tool=tool+add;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="+";

}

});

}

if(i==11)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

jq=Double.parseDouble(ma);

if(what==null)

{

tool=jq;

what="jq";

}

else

{

tool=tool-jq;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="-";

}

});

}

if(i==3)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

cq=Double.parseDouble(ma);

if(what==null)

{

tool=cq;

what="cq";

}

else

{

tool=tool/cq;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="/";

}

});

}

if(i==7)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

cs=Double.parseDouble(ma);

if(what==null)

{

tool=cs;

what="cs";

}

else

{

tool=tool*cs;

text.setText(String.valueOf((tool)));

}

vc.add("a");

vc1.add("v1");

to="*";

}

});

}

if(i==13)

{

b.addActionListener(new ActionListener()

{

public void actionPerformed(ActionEvent e)

{

String ma=text.getText();

dy=Double.parseDouble(ma);

if(what=="add")

{

jg=String.valueOf((tool+dy));

}

if(what=="jq")

{

jg=String.valueOf((tool-dy));

}

if(what=="cs")

{

jg=String.valueOf((tool*dy));

}

if(what=="cq")

{

jg=String.valueOf((tool/dy));

}

if(what==null)

{

if(to=="+")

{

tool=add;

jg=String.valueOf(tool+dy);

}

else if(to=="-")

{

tool=jq;

jg=String.valueOf(dy-tool);

}

else if(to=="*")

{

tool=cs;

jg=String.valueOf(dy*tool);

}

else if(to=="/")

{

tool=cq;

jg=String.valueOf(dy/tool);

}

else

{

jg=String.valueOf(dy);

}

}

text.setText(jg);

Vec.clear();

Vec.add(".");

vc.add("a");

vc1.add("v1");

what=null;

tool=0;

}

});

}

}

}

}

class Centernorth extends JPanel {

public Centernorth() {

final JTextField text=Tool.getinstance().getfield();

}

}

class Centerpanel extends JPanel {

public Centerpanel() {

this.setLayout(new BorderLayout(8,7));

Centernorth cn=new Centernorth();

Centercenter cc=new Centercenter();

Centerwest cw=new Centerwest();

this.add(cn,BorderLayout.NORTH);

this.add(cc,BorderLayout.CENTER);

this.add(cw,BorderLayout.WEST);

}

}

class Centerwest extends JPanel {

public Centerwest() {

}

}

class Northpanel extends JPanel {

private JTextField tf;

public Northpanel() {

tf=Tool.getinstance().getfield();

this.add(tf);

}

}

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

才子_辉祝您愉快！