java前端计算器代码,java开发计算器
求java计算器的代码
import java.awt.*;
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import java.awt.event.*;
import java.util.*;
import javax.swing.*;
public class Calculator extends JFrame{
private float op1,op2;//定义两个变量存放需要运算的值
private String str="";//定义str去和text进行交叉赋值
private String opr,co;//opr存放符合，co用来存放复制的内容
private double re;//用来存放运算的结果
private boolean bo=false;//是否进行了+-*/运算
private boolean btime=false;//时间开关
Container contentpane=this.getContentPane();
JPanel panel1=new JPanel(new BorderLayout()),
panel2=new JPanel(new FlowLayout()),
panel3=new JPanel(new GridLayout(4,5)),
panel4=new JPanel(new BorderLayout()),
panel5=new JPanel(new BorderLayout());
//菜单栏
JMenuBar menubar=new JMenuBar();
JMenu edit=new JMenu("编辑(E)"),
find=new JMenu("查看(V)"),
help=new JMenu("帮助(H)");
JMenuItem copy=new JMenuItem("复制(C)",'C'),
paste=new JMenuItem("粘贴(P)",'P'),
standard=new JMenuItem("标准型(T)",'T'),
science=new JMenuItem("科学型(S)",'S'),
numarray=new JMenuItem("数字分组(I)",'I'),
helptopic=new JMenuItem("帮助主题(H)",'H'),
aboutcal=new JMenuItem("关于计算器(A)",'A');
//输入文本框
JTextField text=new JTextField(25);
//数字键
JButton one=new JButton("1"),
two=new JButton("2"),
three=new JButton("3"),
four=new JButton("4"),
five=new JButton("5"),
six=new JButton("6"),
seven=new JButton("7"),
eight=new JButton("8"),
nine=new JButton("9"),
zero=new JButton("0");
//功能键
JButton division=new JButton("/"),
multiply=new JButton("*"),
addition=new JButton("+"),
subtration=new JButton("-"),
sqrt=new JButton("sqrt"),
residual=new JButton("%"),
sign=new JButton("+/-"),
dot=new JButton("."),
reciprocal=new JButton("1/X"),
amount=new JButton("="),
backspace=new JButton("Backspace"),
ce=new JButton("CE"),
c=new JButton("C"),
time=new JButton("time");
public Calculator() {
contentpane.setLayout(new BorderLayout());
//textField文本从右边开始写
text.setHorizontalAlignment(SwingConstants.RIGHT);
text.setText("0.");
//菜单栏添加
edit.add(copy);
edit.add(paste);
find.add(standard);
find.add(science);
find.addSeparator();
find.add(numarray);
help.add(helptopic);
help.addSeparator();
help.add(aboutcal);
//把组件添加至容器中
menubar.add(edit);
menubar.add(find);
menubar.add(help);
panel1.add(menubar,"North");
panel1.add(text,"West");
//添加数字、功能键至panel2、panel3
panel2.add(backspace);
panel2.add(ce);
panel2.add(c);
panel2.add(time);
panel3.add(seven);
panel3.add(eight);
panel3.add(nine);
panel3.add(division);
panel3.add(sqrt);
panel3.add(four);
panel3.add(five);
panel3.add(six);
panel3.add(multiply);
panel3.add(residual);
panel3.add(one);
panel3.add(two);
panel3.add(three);
panel3.add(subtration);
panel3.add(reciprocal);
panel3.add(zero);
panel3.add(sign);
panel3.add(dot);
panel3.add(addition);
panel3.add(amount);
panel4.add(panel2,"North");
panel4.add(panel3,"West");
panel5.add(panel1,"North");
panel5.add(panel4,"West");
contentpane.add(panel5,"North");
//事件
//助记符
edit.setMnemonic('E');
find.setMnemonic('V');
help.setMnemonic('H');
//快捷键
KeyStroke kcopy=KeyStroke.getKeyStroke(KeyEvent.VK_C,Event.CTRL_MASK);
copy.setAccelerator(kcopy);
KeyStroke kpaste=KeyStroke.getKeyStroke(KeyEvent.VK_V,Event.CTRL_MASK);
paste.setAccelerator(kpaste);
//0-9、.的显示事件
actionlistener1 al1=new actionlistener1();
one.addActionListener(al1);
two.addActionListener(al1);
three.addActionListener(al1);
four.addActionListener(al1);
five.addActionListener(al1);
six.addActionListener(al1);
seven.addActionListener(al1);
eight.addActionListener(al1);
nine.addActionListener(al1);
//小数点的ActionListener事件
dot.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
int count;
count=str.length();
//1.第一位就为.时改变text中内容为："0."
if(count==0){
str="0.";
text.setText(str);
}
//2.不可以重复按"."
else {if(!str.contains(".")){
str+=".";
text.setText(str);
}
else
System.out.println("您再点的话，输入的将不再是小数了！");
}
}
});
//如果第一位是0那么第二位就不可以为0
zero.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
int count;
count=str.length();
if(bo){
if(!(str.contains("0")count==1)){
str="";
str+="0";
text.setText(str);
}else
System.out.println("您再点的话，输入的将不再是数字了！");
}
else{
if(!(str.contains("0")count==1)){
str+="0";
text.setText(str);
}else
System.out.println("您再点的话，输入的将不再是数字了！");
}
bo=false;
}
});
//+、-、*、/、%运算
actionlistener3 al3=new actionlistener3();
addition.addActionListener(al3);
subtration.addActionListener(al3);
multiply.addActionListener(al3);
division.addActionListener(al3);
residual.addActionListener(al3);
//CE和C清空按钮时间
actionlistener2 al2=new actionlistener2();
ce.addActionListener(al2);
c.addActionListener(al2);
//退格键
backspace.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
int count;
count=str.length()-1;
if(bo==false){
if(count=0){
str=str.substring(0,count);
text.setText(str);
}
else
text.setText("0.");
}else
System.out.println("您现在正进行法则运算！");
}
});
//求平方根
sqrt.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
int count;
count=str.length();
if(count!=0){
op1=Float.parseFloat(text.getText());
re=Math.sqrt(op1);
String str1=String.valueOf(re);
text.setText(str1);
str="";
}
else
System.out.println("您现在的按sqrt键毫无意义");
}
});
//求倒数
reciprocal.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
int count;
count=str.length();
if(count!=0){
op1=Float.parseFloat(text.getText());
if(op1!=0){
re=1/op1;
String str1=String.valueOf(re);
text.setText(str1);
str=str1;
}
else{
text.setText("除数不可以为0的");
str="";
}
}
else
System.out.println("您现在的按1/X键毫无意义");
}
});
//=事件
amount.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
op2=Float.parseFloat(str);
//需判断进行那种运算法则
if(opr=="+"){//加法运算
re=op1+op2;
String str1=String.valueOf(re);
text.setText(str1);
str=String.valueOf(re);
}else{
if(opr=="-"){//减法运算
re=op1-op2;
String str1=String.valueOf(re);
text.setText(str1);
str=String.valueOf(re);
}else{
if(opr=="*"){//乘法运算
re=op1*op2;
String str1=String.valueOf(re);
text.setText(str1);
str=String.valueOf(re);
}else{
if(opr=="/"op2!=0){//除法运算
re=op1/op2;
String str1=String.valueOf(re);
text.setText(str1);
str=String.valueOf(re);
}else{
if(opr=="%"){//取余运算
re=op1%op2;
String str1=String.valueOf(re);
text.setText(str1);
str="";
}
else if(op2==0){
text.setText("除数不可以为0的");
str="";
}
}
}
}
}
//打印看看
System.out.print(op1);
System.out.print(opr);
System.out.print(op2+"=");
System.out.print(re);
System.out.println();
}
});
//复制事件
copy.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
int count;
count=str.length();
if(count!=0){
co=text.getText();
}
else
System.out.println("没有可复制的对象");
}
});
//粘贴事件
paste.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
str=co;
text.setText(str);
}
});
//时间事件
time.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
if(btime==false){
String st=(new Date()).toString();
text.setText(st);
str="";
btime=true;
}
else{
text.setText(str);
btime=false;
}
}
});
//+/-事件
sign.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
int a=Integer.valueOf(str);
a=a*(-1);
str=String.valueOf(a);
text.setText(str);
}
});
}
//定义1-9按钮在text中显示的内部类
class actionlistener1 implements ActionListener{
public void actionPerformed(ActionEvent e){
JButton button=(JButton)e.getSource();
String btext=button.getText();
//如果第一位为0再输入其他非零的整数时将零忽略
if(bo){
if(str.indexOf("0")==0str.length()==1){
str="";
str+=btext;
text.setText(str);
}else{
str="";
str+=btext;
text.setText(str);}
}else{
if(str.indexOf("0")==0str.length()==1){
str="";
str+=btext;
text.setText(str);
}else{
str+=btext;
text.setText(str);
}
}
bo=false;
}
}
//定义清空text中内容的内部类
class actionlistener2 implements ActionListener{
public void actionPerformed(ActionEvent e){
str="";
text.setText("0.");
}
}
//定义+、-、*、/、%运算的内部类
class actionlistener3 implements ActionListener{
public void actionPerformed(ActionEvent e){
int count;
count=str.length();
if(count!=0){
JButton button=(JButton)e.getSource();
opr=button.getText();
op1=Float.parseFloat(str);
bo=true;
}
else
System.out.println("您现在的按键毫无意义！");
}
}
public static void main(String[] args){
Calculator cc=new Calculator();
cc.pack();
cc.setResizable(false);//不可最大化
cc.setVisible(true);
cc.setTitle("计算器");
cc.setDefaultCloseOperation(EXIT_ON_CLOSE);
Dimension scmsize=Toolkit.getDefaultToolkit().getScreenSize();
int w=cc.getSize().width;
int h=cc.getSize().height;
int x=(scmsize.width-w)/2;
int y=(scmsize.height-h)/2;
cc.setLocation(x, y);
}
}
求大神发个完整简单的java计算器代码，
public static void main(String[] args) {
System.out.println("简单计算器");
boolean flag=true;//while循环是否继续，true继续循环，false停止循环
System.out.println("请输入第一个数字");
while(flag){
Scanner scan = new Scanner(System.in);
String bh=scan.next();
try {
double num = Double.parseDouble(bh);
System.out.println("请输入符号(+、-、*、/)");
while(1==1){
String fh=scan.next();
if("+".equals(fh) || "-".equals(fh) || "*".equals(fh) || "/".equals(fh)){
System.out.println("请输入第二个数字");
while(1==1){
String bh2=scan.next();
try {
double num2 = Double.parseDouble(bh2);
double num3=0;
if("+".equals(fh)){
num3=num+num2;
}else if("-".equals(fh)){
num3=num-num2;
}else if("*".equals(fh)){
num3=num*num2;
}else if("/".equals(fh)){
num3=num/num2;
}
System.out.println(num3);
break;
} catch (Exception e) {
System.out.println("请输入第二个正确的数字");
continue;
}
}
break;
}else{
System.out.println("请输入正确的符号(+、-、*、/)");
continue;
}
}
System.out.println("是否继续运算:输入Y或者y继续，输入其它任意字符退出");
String yn=scan.next();
if("Y".equals(yn) || "y".equals(yn)){
continue;
}else{
System.out.println("运算结束");
break;
}
}catch (NumberFormatException e) {//输入非数字类型时
System.out.println("请输入第一个正确的数字");
continue;
}
}
}
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
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.=/";
ArrayListString arrayList = new ArrayListString();//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;iallButtons.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;iallButtons.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;iallButtons.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 ArrayListString getResult(ArrayListString list){
String res = null;
String[] s = {"/","*","-","+"};
int i=0;
if(list.size()1){
for(;is.length;){
if(s[i].equals("/")){
for(int j=0;jlist.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;jlist.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;jlist.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;jlist.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;kc.length;k++){
c[k] = res.charAt(k);
}
for(int k=0;kc.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();
}
}
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);
}
}
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