计算器的java代码
Ⅰ 求用java实现计算器的代码（可实用的，没语法错误的）
import java.awt.BorderLayout; import java.awt.Color; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JTextField; import javax.swing.border.TitledBorder; //导包 public class Jisuanqi extends JFrame implements ActionListener { //继承JFrame 实现事件监听 private JTextField reasult; private JButton btn1, btn2, btn3, btn4, btn5, btn6, btn7, btn8, btn9, btn0, btnAC, btnAdd, btnSub, btnReasult, btnD, btnAbout, btnCancel; private boolean add, sub, end, s, c; private String str; private double num1, num2; public Jisuanqi() { //构造属性 JPanel p1 = new JPanel(); JPanel p2 = new JPanel(); JPanel p3 = new JPanel(); TitledBorder tb = new TitledBorder("输出"); tb.setTitleColor(Color.BLUE); //标题边框底端线 设置颜色 btnAbout = new JButton(" 关于 "); btnCancel = new JButton("Cancel"); //两个按钮 btnCancel.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent ee) { System.exit(0); } }); //给Cancel添加事件监听 当鼠标点击时 程序结束 btnAbout.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent ee) { JOptionPane.showMessageDialog(null, "黄盖！！", "消息", JOptionPane.INFORMATION_MESSAGE); } //给“关于”添加事件监听 当鼠标点击时 弹出对话框 显示黄盖 }); p3.add(btnAbout); p3.add(btnCancel); // JPanel p4=new JPanel(); // JPanel p5=new JPanel(); // reasult.setBorder(tb); reasult = new JTextField("0", 20); reasult.setEditable(false); //设置不能修改 reasult.setHorizontalAlignment(JTextField.RIGHT); // 设置文本的水平对齐方式。 reasult.setForeground(Color.BLUE); //颜色 p1.setBorder(tb); p1.add(reasult); btn0 = new JButton("0"); btn0.addActionListener(this); btn1 = new JButton("1"); btn1.addActionListener(this); btn2 = new JButton("2"); btn2.addActionListener(this); btn3 = new JButton("3"); btn3.addActionListener(this); btn4 = new JButton("4"); btn4.addActionListener(this); btn5 = new JButton("5"); btn5.addActionListener(this); btn6 = new JButton("6"); btn6.addActionListener(this); btn7 = new JButton("7"); btn7.addActionListener(this); btn8 = new JButton("8"); btn8.addActionListener(this); btn9 = new JButton("9"); btn9.addActionListener(this); btnD = new JButton("."); btnD.addActionListener(this); btnD.setForeground(Color.RED); btnAC = new JButton("AC"); btnAC.addActionListener(this); btnAC.setBackground(Color.PINK); btnAdd = new JButton("+"); btnAdd.addActionListener(this); btnAdd.setForeground(Color.BLUE); btnSub = new JButton("—"); btnSub.addActionListener(this); btnSub.setForeground(Color.BLUE); btnReasult = new JButton("="); btnReasult.addActionListener(this); btnReasult.setForeground(Color.RED); //事件监听 + 颜色 p2.add(btn1); p2.add(btn2); p2.add(btn3); p2.add(btn4); p2.add(btn5); p2.add(btn6); p2.add(btn7); p2.add(btn8); p2.add(btn9); p2.add(btn0); p2.add(btnD); p2.add(btnAC); p2.add(btnAdd); p2.add(btnSub); p2.add(btnReasult); //面板上添加按钮 p2.setLayout(new GridLayout(5, 3)); //面板上设置对齐方式 add(p1, BorderLayout.NORTH); add(p2, BorderLayout.CENTER); add(p3, BorderLayout.SOUTH); //将p1 p2 p3 面板对象添加到JFrame } public void num(int i) { String s = null; s = String.valueOf(i); if (end) { // 如果数字输入结束，则将文本框置零，重新输入 reasult.setText("0"); end = false; } if ((reasult.getText()).equals("0")) { // 如果文本框的内容为零，则覆盖文本框的内容 reasult.setText(s); } else { // 如果文本框的内容不为零，则在内容后面添加数字 str = reasult.getText() + s; reasult.setText(str); } }/* * * String s=null; * * s=String.valueOf(i); * * str=reasult.getText()+s; * * reasult.setText(str); * * } */ public void actionPerformed(ActionEvent e) { if (e.getSource() == btn1) num(1); else if (e.getSource() == btn2) num(2); else if (e.getSource() == btn3) num(3); else if (e.getSource() == btn4) num(4); else if (e.getSource() == btn5) num(5); else if (e.getSource() == btn6) num(6); else if (e.getSource() == btn7) num(7); else if (e.getSource() == btn8) num(8); else if (e.getSource() == btn9) num(9); else if (e.getSource() == btn0) num(0); else if (e.getSource() == btnAdd) { sign(1); btnD.setEnabled(true); } else if (e.getSource() == btnSub) { sign(2); btnD.setEnabled(true); } else if (e.getSource() == btnAC) { btnD.setEnabled(true); reasult.setText("0"); } else if (e.getSource() == btnD) { str = reasult.getText(); str += "."; reasult.setText(str); btnD.setEnabled(false); } else if (e.getSource() == btnReasult) { btnD.setEnabled(true); num2 = Double.parseDouble(reasult.getText()); if (add) { num1 = num1 + num2; } else if (sub) { num1 = num1 - num2; } reasult.setText(String.valueOf(num1)); end = true; } } public void sign(int s) { if (s == 1) { add = true; sub = false; } else if (s == 2) { add = false; sub = true; } num1 = Double.parseDouble(reasult.getText()); end = true; } //设计计算的过程 public static void main(String[] args) { Jisuanqi j = new Jisuanqi(); j.setTitle("+/-简易计算器"); j.setLocation(500, 280); j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //默认关闭可以关闭程序 j.setResizable(false); j.pack(); j.setVisible(true); } } 这个计算机，绝对让你满意
Ⅱ 用JAVA编写的科学计算器源代码
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
class Counter extends WindowAdapter
{
static JFrame f=new JFrame("计算器");
static JTextField text1=new JTextField("0.");
static String source="";
static String cal="";
static String object="";
static boolean flag=false;
static boolean flag1=true;
static boolean flag2=false;
public void init()
{
try
{
Container c=f.getContentPane();
JPanel pan1=new JPanel();
JButton b1=new JButton("1");
JButton b2=new JButton("2");
JButton b3=new JButton("3");
JButton b4=new JButton("4");
JButton b5=new JButton("5");
JButton b6=new JButton("6");
JButton b7=new JButton("7");
JButton b8=new JButton("8");
JButton b9=new JButton("9");
JButton b0=new JButton("0");
JButton b11=new JButton("+");
JButton b12=new JButton("-");
JButton b13=new JButton("*");
JButton b14=new JButton("/");
JButton b15=new JButton(".");
JButton b16=new JButton("=");
JButton bclar=new JButton("清零");
text1.setHorizontalAlignment(JTextField.RIGHT);
c.add(text1,"North");
c.add(pan1);
A aa=new A();
Result re=new Result();
Opertion op=new Opertion();
Clar cl=new Clar();
b1.addActionListener(aa);
b2.addActionListener(aa);
b3.addActionListener(aa);
b4.addActionListener(aa);
b5.addActionListener(aa);
b6.addActionListener(aa);
b7.addActionListener(aa);
b8.addActionListener(aa);
b9.addActionListener(aa);
b0.addActionListener(aa);
b11.addActionListener(op);
b12.addActionListener(op);
b13.addActionListener(op);
b14.addActionListener(op);
b16.addActionListener(re);
b15.addActionListener(aa);
bclar.addActionListener(cl);
pan1.add(b1);
pan1.add(b2);
pan1.add(b3);
pan1.add(b11);
pan1.add(b4);
pan1.add(b5);
pan1.add(b6);
pan1.add(b12);
pan1.add(b7);
pan1.add(b8);
pan1.add(b9);
pan1.add(b13);
pan1.add(b0);
pan1.add(b15);
pan1.add(b16);
pan1.add(b14);
pan1.add(bclar);
f.setSize(200,220);
f.setVisible(true);
}
catch(Exception e)
{
System.out.println(e.getMessage());
}
}
class A implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String a=text1.getText();
String s=e.getActionCommand();
if(a.equals("0.")||a.equals("+")||a.equals("-")||a.equals("*")||a.equals("/"))
text1.setText(s);
else {
if(flag2)
{
text1.setText(s);
flag2=false;
}
else
text1.setText(a+s);
}
}
}
class Opertion implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
cal=e.getActionCommand();
if(flag1==true)
source=text1.getText();
text1.setText(cal);
flag1=false;
flag=true;
}
}
class Result implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
double num1;
num1=Double.parseDouble(source);
object=text1.getText();
double num2;
num2=Double.parseDouble(object);
double result=0;
if(cal.equals("+"))
result=num1+num2;
if(cal.equals("-"))
result=num1-num2;
if(cal.equals("*"))
result=num1*num2;
if(cal.equals("/"))
if(num2==0)
text1.setText("除数不能为0");
else
result=num1/num2;
String s1=Double.toString(result);
text1.setText(s1);
flag1=true;
flag2=true;
}
}
class Clar implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
text1.setText("0.");
}
}
public static void main(String[] args)
{
Counter count=new Counter();
count.init();
}
public void windowClosing(WindowEvent e){
System.exit(1);
}
public void windowOpened(WindowEvent e){}
public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowClosed(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}
}
Ⅲ 用JAVA编写一个简单的计算器，要求如下:
以下是上图计算器的代码:
packageComputer;
importjava.awt.BorderLayout;
importjava.awt.Color;
importjava.awt.Container;
importjava.awt.Font;
importjava.awt.GridLayout;
importjava.awt.event.ActionEvent;
importjava.awt.event.ActionListener;
importjava.util.Stack;
importjavax.swing.JApplet;
importjavax.swing.JButton;
importjavax.swing.JFrame;
importjavax.swing.JPanel;
importjavax.swing.JTextField;
{
/**
*
*/
=1L;
privateJTextFieldtextField=newJTextField("请输入");
Stringoperator="";//操作
Stringinput="";//输入的式子
booleanflag=true;
//booleanflag1=true;
//booleanflag2=true;
publicvoidinit()//覆写Applet里边的init方法
{
ContainerC=getContentPane();
JButtonb[]=newJButton[16];
JPanelpanel=newJPanel();
C.add(textField,BorderLayout.NORTH);
C.add(panel,BorderLayout.CENTER);
panel.setLayout(newGridLayout(4,4,5,5));
Stringname[]={"7","8","9","+","4","5","6","-","1","2","3","*","0","C","=","/"};//设置按钮
for(inti=0;i<16;i++)//添加按钮
{
b[i]=newJButton(name[i]);
b[i].setBackground(newColor(192,192,192));
b[i].setForeground(Color.BLUE);//数字键设置为蓝颜色
if(i%4==3)
b[i].setForeground(Color.RED);
b[i].setFont(newFont("宋体",Font.PLAIN,16));//设置字体格式
panel.add(b[i]);
b[i].addActionListener(this);
}
b[13].setForeground(Color.RED);//非数字键，即运算键设置为红颜色
b[13].setForeground(Color.RED);
}
publicvoidactionPerformed(ActionEvente)
{
intcnt=0;
StringactionCommand=e.getActionCommand();
if(actionCommand.equals("+")||actionCommand.equals("-")||actionCommand.equals("*")||actionCommand.equals("/"))
input+=""+actionCommand+"";//设置输入，把输入的样式改成需要的样子
elseif(actionCommand.equals("C"))
input="";
elseif(actionCommand.equals("="))//当监听到等号时，则处理input
{
input+="="+compute(input);
textField.setText(input);
input="";
cnt=1;
}
else
input+=actionCommand;//数字为了避免多位数的输入不需要加空格
if(cnt==0)
textField.setText(input);
}
privateStringcompute(Stringinput)//即1237的样例
{
Stringstr[];
str=input.split("");
Stack<Double>s=newStack<Double>();
doublem=Double.parseDouble(str[0]);
s.push(m);
for(inti=1;i<str.length;i++)
{
if(i%2==1)
{
if(str[i].compareTo("+")==0)
{
doublehelp=Double.parseDouble(str[i+1]);
s.push(help);
}
if(str[i].compareTo("-")==0)
{
doublehelp=Double.parseDouble(str[i+1]);
s.push(-help);
}
if(str[i].compareTo("*")==0)
{
doublehelp=Double.parseDouble(str[i+1]);
doubleans=s.peek();//取出栈顶元素
s.pop();//消栈
ans*=help;
s.push(ans);
}
if(str[i].compareTo("/")==0)
{
doublehelp=Double.parseDouble(str[i+1]);
doubleans=s.peek();
s.pop();
ans/=help;
s.push(ans);
}
}
}
doubleans=0d;
while(!s.isEmpty())
{
ans+=s.peek();
s.pop();
}
Stringresult=String.valueOf(ans);
returnresult;
}
publicstaticvoidmain(Stringargs[])
{
JFrameframe=newJFrame("Count");
Countapplet=newCount();
frame.getContentPane().add(applet,BorderLayout.CENTER);
applet.init();//applet的init方法
applet.start();//线程开始
frame.setSize(350,400);//设置窗口大小
frame.setVisible(true);//设置窗口可见
}
}
Ⅳ JAVA 编写计算器 要代码最简单的
学java的时候自己编的，很简单，能够连续输入计算式后进行计算
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.NumberFormat;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
/**简易计算器，能够进行简单的计算
*
* @see 2008.12.9
*/
public class CalculatorA
implements ActionListener{
private JFrame frame;
private JTextField field;
private JButton[] allButtons;
private JButton clearButton;
// private JButton backButton;
String result="";//保存结果
StringBuilder sb = new StringBuilder();//保存要进行的计算式
int x = 0; //用来判断上一次的事件类型
String str = "123+456-789*0.=/";
ArrayList<String> arrayList = new ArrayList<String>();//保存计算式，通过方法进行运算
public CalculatorA(){
frame = new JFrame("我的计算器v1.1");
frame.setLocation(300,300);
field = new JTextField(25);
allButtons = new JButton[16];
for(int i=0;i<allButtons.length;i++){
allButtons[i]= new JButton(str.substring(i,i+1));
}
clearButton = new JButton("CLEAR");
// backButton = new JButton("<——");
init();
setFondAndColor();
addEventHander();
}
public void init(){
frame.setLayout(new BorderLayout());
JPanel northPanel = new JPanel();
JPanel centerPanel = new JPanel();
JPanel southPanel = new JPanel();
northPanel.setLayout(new FlowLayout());
centerPanel.setLayout(new GridLayout(4,4));
southPanel.setLayout(new FlowLayout());
northPanel.add(field);
for(int i=0;i<allButtons.length;i++){
centerPanel.add(allButtons[i]);
}
southPanel.add(clearButton);
//southPanel.add(backButton);
frame.add(northPanel,BorderLayout.NORTH);
frame.add(centerPanel,BorderLayout.CENTER);
frame.add(southPanel,BorderLayout.SOUTH);
}
//设置输入字体
public void setFondAndColor(){
field.setFont(new Font("宋体",Font.BOLD,24));
field.setBackground(new Color(100,200,200));
field.setForeground(Color.RED);
//设置字体从右起始
field.setHorizontalAlignment(JTextField.RIGHT);
}
public void showMi(){
frame.pack();
frame.setResizable(false);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void addEventHander(){
for(int i=0;i<allButtons.length;i++){
allButtons[i].addActionListener(this);
}
clearButton.addActionListener(this);
// backButton.addActionListener(this);
}
@Override
public void actionPerformed(ActionEvent e) {
String str = e.getActionCommand();//取得当前事件返回的值
if("0123456789.".indexOf(str)!=-1){
if(x == 0){ //当x为0时表示还没有进行输入
result=str;
sb.append(str);
field.setText(str);
x = 1;
}
else if(x == 1){
result = result +str;
sb.append(str);
field.setText(result);
x = 1;
}
else if(x == 2){
sb.delete(0,sb.length());
result = result+str;
sb.append(str);
field.setText(result);
x = 1;
}
else if(x == 3){
result = str;
sb.delete(0,sb.length());
arrayList.clear();
field.setText(str);
sb.append(str);
field.setText(str);
x = 1;
}
else if(x == 4){
result ="";
sb.delete(0,sb.length());
arrayList.clear();
result = str;
sb.append(str);
field.setText(str);
x = 1;
}
else{
result = result +str;
sb.append(str);
field.setText(result);
x = 1;
}
}
else if("+*-/".indexOf(str)!=-1){
if(x == 0){
field.setText("");
x = 2;
}
else if(x == 1){
result = result + str;
arrayList.add(sb.toString());
arrayList.add(str);
sb.append(str);
field.setText(result);
x = 2;
}
else if(x == 2){
x = 2;
}
else if(x == 3){
field.setText(result+str);
arrayList.add(result);
arrayList.add(str);
result = result+str;
x = 2;
}
else if(x == 4){
result ="";
sb.delete(0,sb.length());
arrayList.clear();
x = 2;
}
else{
field.setText(result+str);
arrayList.add(result);
arrayList.add(str);
result = result+str;
x = 2;
}
}
else if("=".equals(str)){
if(x == 0){
field.setText("0");
arrayList.clear();
result = "0";
x = 3;
}
else if(x == 1){
try{
arrayList.add(sb.toString());
arrayList = getResult(arrayList);
result = arrayList.get(0);
field.setText(result);
arrayList.clear();
x = 3;
}catch(Exception e1){
field.setText("数据格式异常");
x = 0;
}
}
else if(x == 2){
field.setText("数据格式错误.....");
arrayList.clear();
x = 0;
}
else if(x == 3){
field.setText(result);
x = 3;
}
else if(x == 4){
result ="";
sb.delete(0,sb.length());
arrayList.clear();
x = 3;
}
else {
try{
arrayList.add(sb.toString());
arrayList = getResult(arrayList);
result = arrayList.get(0);
field.setText(result);
arrayList.clear();
x = 3;
}catch(Exception e1){
field.setText("数据格式异常");
x = 0;
}
}
}
else if("CLEAR".equals(str)){
arrayList.clear();
field.setText("0");
arrayList.add("0");
x = 4;
}
else{
if(result.length()>1){
result = result.substring(0,result.length()-1);
if(sb.length()>0){
sb.delete(sb.length()-1,sb.length());
}
else {
sb.delete(0,1);
}
field.setText(result);
x = 5;
}
else{
result = "";
sb.delete(0,sb.length());
arrayList.clear();
field.setText("0");
x = 0;
}
}
}
public static ArrayList<String> getResult(ArrayList<String> list){
String res = null;
String[] s = {"/","*","-","+"};
int i=0;
if(list.size()>1){
for(;i<s.length;){
if(s[i].equals("/")){
for(int j=0;j<list.size();j++){
if(list.get(j).equals(s[i])){
res = Double.toString(Double.parseDouble(list.get(j-1))/Double.parseDouble(list.get(j+1)));
//本地的数据格式
NumberFormat nf = NumberFormat.getInstance();
res = nf.format(Double.parseDouble(res));
res = getChange(res);
list.set(j-1,res);
list.remove(j);
list.remove(j);
getResult(list);
}
}
i++;
}
else if(s[i].equals("*")){
for(int j=0;j<list.size();j++){
if(list.get(j).equals(s[i])){
res = Double.toString(Double.parseDouble(list.get(j-1))*Double.parseDouble(list.get(j+1)));
NumberFormat nf = NumberFormat.getInstance();
res = nf.format(Double.parseDouble(res));
res = getChange(res);
list.set(j-1,res);
list.remove(j);
list.remove(j);
getResult(list);
}
}
i++;
}
else if(s[i].equals("-")){
for(int j=0;j<list.size();j++){
if(list.get(j).equals(s[i])){
res = Double.toString(Double.parseDouble(list.get(j-1))-Double.parseDouble(list.get(j+1)));
NumberFormat nf = NumberFormat.getNumberInstance();
res = nf.format(Double.parseDouble(res));
res = getChange(res);
list.set(j-1,res);
list.remove(j);
list.remove(j);
getResult(list);
}
}
i++;
}
else {
for(int j=0;j<list.size();j++){
if(list.get(j).equals(s[i])){
res = Double.toString(Double.parseDouble(list.get(j-1))+Double.parseDouble(list.get(j+1)));
NumberFormat nf = NumberFormat.getInstance();
res = nf.format(Double.parseDouble(res));
res = getChange(res);
list.set(j-1,res);
list.remove(j);
list.remove(j);
getResult(list);
}
}
i++;
}
}
}
return list;
}
//对数字字符串进行排除不必要符号
public static String getChange(String res){
String s_temp = "";
char[] c = new char[res.length()];
for(int k=0;k<c.length;k++){
c[k] = res.charAt(k);
}
for(int k=0;k<c.length;k++){
if((c[k]>= '0' && c[k]<= '9')|| c[k] == '.'){
s_temp += c[k];
}
}
return s_temp;
}
public static void main(String[] args){
new CalculatorA().showMi();
}
}
Ⅳ 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 HashMap<String, Operator> operators = new HashMap<String, Operator>();
private HashMap<String, Processor> processors = new HashMap<String, 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);
}
}
Ⅵ java计算器代码
import java.awt.*;
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;i<name.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;i<name.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
Ⅶ 怎么用JAVA编程编写一个计算器
打开IED：打开自己java编程的软件，采用的是eclipse软件。
建立java工程。
编写类。