java写计算器程序代码
import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Color;
import java.awt.Dialog;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridLayout;
import java.awt.Label;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.Panel;
import java.awt.TextField;
import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.StringSelection;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class Calculator extends Frame implements ActionListener {
private String s_show;
private String s_go;
Panel p1 = new Panel();
Panel p2 = new Panel();
Panel p3=new Panel();
Oper do1 = new Oper();
TextField textfields = new TextField(27);
Dialog dlog=new Dialog(this,"about us");
Label aboutlab=new Label();
String s1;
String sedit;
Button buttons1 = new Button("Backspace");
int screenWidth,screenHeight;
Clipboard clp=Toolkit.getDefaultToolkit().getSystemClipboard();
Calculator() {
this.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
MenuBar mbr=new MenuBar();
setMenuBar(mbr);
Menu edit=new Menu(" do ");
MenuItem =new MenuItem("Copy Ctrl+C");
MenuItem zhantie=new MenuItem(" Ctrl+V");
MenuItem exit=new MenuItem("Close Alt+F4");
edit.add();
edit.add(zhantie);
mbr.add(edit);
Menu help=new Menu(" help ");
MenuItem help1=new MenuItem("help theme");
MenuItem about=new MenuItem("about us");
dlog.setAlwaysOnTop(true);
dlog.setResizable(false);
//dlog.setEnabled(false);
s1="学习时兴趣小组做的";
aboutlab.setSize(200, 150);
aboutlab.setText(s1);
dlog.add(aboutlab);
about.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent e){
dlog.setVisible(true);
}
});
dlog.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
dlog.setVisible(false);
}
});
help.add(help1);
help.add(about);
mbr.add(help);
p1.setBackground(Color.lightGray);
p1.setForeground(Color.red);
p2.setBackground(Color.lightGray);
p2.setForeground(Color.blue);
p1.setLayout(new FlowLayout(FlowLayout.RIGHT, 1,1));
p1.add(textfields);
p1.add(buttons1);
buttons1.addActionListener(this);
p2.setLayout(new GridLayout(5, 4, 10, 16));
this.add(p1, BorderLayout.CENTER);
this.add(p2, BorderLayout.SOUTH);
this.setTitle("Play the window");
this.setResizable(false);
this.setAlwaysOnTop(true);
/**textfields.addKeyListener(new KeyAdapter(){
public void keyTyped(KeyEvent e){
char c=e.getKeyChar();
String textfieldsstr=textfields.toString();
switch(c){
case 1:textfields.setText(textfieldsstr+1);break;
case 2:textfields.setText(textfields.toString()+2);break;
case 3:textfields.setText(textfields.toString()+3);break;
case 4:textfields.setText(textfields.toString()+4);break;
case 5:textfields.setText(textfields.toString()+5);break;
case 6:textfields.setText(textfields.toString()+6);break;
case 7:textfields.setText(textfields.toString()+7);break;
case 8:textfields.setText(textfields.toString()+8);break;
case 9:textfields.setText(textfields.toString()+9);break;
case 0:textfields.setText(textfields.toString()+0);break;
case '*':textfields.setText(textfields.toString()+"*");break;
}
/**if(e.getKeyChar()==1){
textfields.setText(textfields.toString()+1);
}
}
});*///未实现键盘监听
Toolkit tk=Toolkit.getDefaultToolkit();
Dimension screenSize = tk.getScreenSize();
screenWidth=screenSize.width;
screenHeight=screenSize.height;
this.setBounds(screenWidth/2-150, screenHeight/2-128, 300, 256);
dlog.setBounds(screenWidth/2-100, screenHeight/2-78, 200, 150);
int i, j = 0, k = 9, r1 = 0, r2 = 0, r3 = 0;
for (i = 0; i < 20; i++) {
j++;
if (j == 4) {
j = 0;
r1++;
Button buttons2_i = new Button();
p2.add(buttons2_i);
buttons2_i.setBackground(Color.cyan);
buttons2_i.addActionListener(this);
switch (r1) {
case 1:
buttons2_i.setLabel("+");
break;
case 2:
buttons2_i.setLabel("-");
break;
case 3:
buttons2_i.setLabel("*");
break;
case 4:
buttons2_i.setLabel("/");
break;
case 5:
buttons2_i.setLabel("=");
break;
}
}// endif
else // else1
{
if (i < 3) {
r2++;
Button buttons2_i = new Button(""); //
p2.add(buttons2_i);
buttons2_i.setBackground(Color.cyan);
buttons2_i.addActionListener(this);
switch (r2) {
case 1:
buttons2_i.setLabel("(");
break;
case 2:
buttons2_i.setLabel(")");
break;
case 3:
buttons2_i.setLabel("sqrt");
break;
}
}// endif
else {
if (i > 16 && i < 19) {
r3++;
Button buttons2_i = new Button("");
p2.add(buttons2_i);
buttons2_i.addActionListener(this);
switch (r3) {
case 1:
buttons2_i.setLabel(".");
break;
case 2:
buttons2_i.setLabel("CE");
break;
}
}// endif
else {
Integer name = new Integer(k);
k--;
s_show = name.toString();
Button buttons2_i = new Button(s_show);
p2.add(buttons2_i);
buttons2_i.addActionListener(this);
}
}
}// end else1
}// end for
s_show = "";
s_go = "";
this.setVisible(true);
}// end Calculator()构造方法
public void actionPerformed(ActionEvent e) {
if (e.getSource() instanceof Button) // if1
{
if (e.getActionCommand() == "CE")// Del
{
s_show = "";
s_go = "";
textfields.setText(s_show);
} else if (e.getActionCommand() == "Backspace") {
if (s_show.equals("")) {
s_go = "";
textfields.setText("");
} else {
if (s_go.length() > 0)
s_go = s_go.substring(0, s_go.length() - 1);
s_show = s_show.substring(0, s_show.length() - 1);
textfields.setText(s_show);
}
} else if (e.getActionCommand() == ".") {
if (textfields.getText().equals(""))
textfields.setText("0.");
else {
s_show += e.getActionCommand();
s_go += e.getActionCommand();
textfields.setText(s_show);
}
} else {
if (e.getActionCommand() != "=") {
if (e.getActionCommand().equals("sqrt")) {
s_show += e.getActionCommand();
s_go += e.getActionCommand();
textfields.setText(s_show);
s_go = s_go.substring(0, s_go.length() - 3);
} else {
s_show += e.getActionCommand();
s_go += e.getActionCommand();
textfields.setText(s_show);
}
} else {
s_show += e.getActionCommand();
s_go += e.getActionCommand();
textfields.setText(do1.operator(s_go)); // ().toString()
}
}// end else
}// end if1
if(e.getSource()==""){
sedit=textfields.getSelectedText();
StringSelection text=new StringSelection(sedit);
clp.setContents(text, null);
}
/**else if(e.getSource()=="zhantie"){
Transferable contents=clp.getContents(this);//返回表示剪贴板当前内容的 transferable 对象。
DataFlavor flavor=DataFlavor.stringFlavor;//
String ss;
if (contents.isDataFlavorSupported(flavor)) {
try
{
int start=textfields.getSelectionStart();
int end=textfields.getSelectionEnd();
//textfields.replaceRange("",start,end);
textfields.setText(ss);
ss = (String)contents.getTransferData(flavor);
int n=textfields.getCaretPosition();
textfields.insert(ss,n);
}catch(Exception ee){
// TODO: handle exception
}
}
}*///未实现剪贴板粘贴功能
// end actionPerformed()
// end class Calculator
}
public static void main(String args[]) {
Calculator cal = new Calculator();
}
}
2. 编写java application程序实现一个简易计算器
Java计算器源代码：
importjava.awt.*;
importjava.awt.event.*;
importjavax.swing.*;
/**********************Java计算器主类*********************/
{
JFramef;
JMenumEdit;
JMenumView;
JMenumHelp;
JMenuItemmCopy;
JMenuItemmPaste;
JTextFieldtResult;
JButtonbNumber;
JButtonbOperator;
JButtonbOther;
JButtonbM;
booleanisDouble=false;//是否为实数
intopFlag=-1;
staticdoublet1=0,t2=0,t3=0,result=0;
staticintopflag1=-1,opflag2=-1,flag=0,resflag=1;
intpreOp,currentOp=0;//标准位
doubleop1=0,op2=0;//操作数
doublen3;
StringBufferbuf=newStringBuffer(20);
StringBufferBoard=newStringBuffer(20);//剪贴板
StringBuffermemory=newStringBuffer(20);//M系列
StringBufferstr=newStringBuffer();
//Java计算器构造器
publicSunnyCalculator()
{
f=newJFrame("Sunny计算器_杨梅树的盔甲");
ContainercontentPane=f.getContentPane();
/**************************Java计算器菜单的创建*****************************/
野升JMenuBarmBar=newJMenuBar();
mBar.setOpaque(true);
mEdit=newJMenu("编辑(E)");
mEdit.setMnemonic(KeyEvent.VK_E);
mCopy=newJMenuItem("复制(C)");
mEdit.add(mCopy);
mPaste=newJMenuItem("粘贴(P)");
mEdit.add(mPaste);
mView=newJMenu("查看(V)");
mView.setMnemonic(KeyEvent.VK_V);
旦仔mView.add(newJMenuItem("标准型"));
mView.add(newJMenuItem("科学型"));
mView.addSeparator();
mView.add(newJMenuItem("查看分组"));
mHelp=newJMenu("帮助(H)");
mHelp.setMnemonic(KeyEvent.VK_H);
mHelp.add(newJMenuItem("帮助主题"));
mHelp.addSeparator();
mHelp.add(newJMenuItem("关于计算器"));
mBar.add(mEdit);
mBar.add(mView);
mBar.add(mHelp);
f.setJMenuBar(mBar);
contentPane.setLayout(newBorderLayout());
JPanelpTop=newJPanel();
tResult=newJTextField("0.",26);
tResult.setHorizontalAlignment(JTextField.RIGHT);
tResult.setEditable(false);
pTop.add(tResult);
contentPane.add(pTop,BorderLayout.NORTH);
JPanelpBottom=new模脊汪JPanel();
pBottom.setLayout(newBorderLayout());
JPanelpLeft=newJPanel();
pLeft.setLayout(newGridLayout(5,1,3,3));
bM=newJButton("");
bM.setEnabled(false);
pLeft.add(bM);
/*************************Java计算器功能键定义***************************/
bOther=newJButton("MC");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(newInsets(3,2,3,2));
pLeft.add(bOther);
bOther=newJButton("MR");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(newInsets(3,2,3,2));
pLeft.add(bOther);
bOther=newJButton("MS");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(newInsets(3,2,3,2));
pLeft.add(bOther);
bOther=newJButton("M+");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(newInsets(3,2,3,2));
pLeft.add(bOther);
pBottom.add(pLeft,BorderLayout.WEST);
JPanelpRight=newJPanel();
pRight.setLayout(newBorderLayout());
JPanelpUp=newJPanel();
pUp.setLayout(newGridLayout(1,3,3,0));
bOther=newJButton("BackSpace");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
bOther.setMargin(newInsets(3,0,3,5));
pUp.add(bOther);
bOther=newJButton("CE");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
pUp.add(bOther);
bOther=newJButton("C");
bOther.addActionListener(this);
bOther.setForeground(Color.red);
pUp.add(bOther);
/***************************Java计算器数字键盘区定义**************************/
JPanelpDown=newJPanel();
pDown.setLayout(newGridLayout(4,5,3,2));
bNumber=newJButton("7");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bNumber=newJButton("8");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bNumber=newJButton("9");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bOperator=newJButton("/");
bOperator.setForeground(Color.red);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,0,3,0));
pDown.add(bOperator);
bOperator=newJButton("sqrt");
bOperator.addActionListener(this);
bOperator.setForeground(Color.red);
bOperator.setMargin(newInsets(3,0,3,0));
pDown.add(bOperator);
bNumber=newJButton("4");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
bNumber.setHorizontalTextPosition(JButton.LEFT);
pDown.add(bNumber);
bNumber=newJButton("5");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bNumber=newJButton("6");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bOperator=newJButton("*");
bOperator.setForeground(Color.red);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,3,3,3));
pDown.add(bOperator);
bOperator=newJButton("%");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,3,3,3));
pDown.add(bOperator);
bNumber=newJButton("1");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bNumber=newJButton("2");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bNumber=newJButton("3");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bOperator=newJButton("-");
bOperator.setForeground(Color.red);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,3,3,3));
pDown.add(bOperator);
bOperator=newJButton("1/x");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
pDown.add(bOperator);
bNumber=newJButton("0");
bNumber.setForeground(Color.blue);
bNumber.addActionListener(this);
bNumber.setMargin(newInsets(3,3,3,3));
pDown.add(bNumber);
bOperator=newJButton("+/-");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,3,3,3));
pDown.add(bOperator);
bOperator=newJButton(".");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,3,3,3));
pDown.add(bOperator);
bOperator=newJButton("+");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,3,3,3));
pDown.add(bOperator);
bOperator=newJButton("=");
bOperator.setForeground(Color.blue);
bOperator.addActionListener(this);
bOperator.setMargin(newInsets(3,3,3,3));
pDown.add(bOperator);
pRight.add(pUp,BorderLayout.NORTH);
pRight.add(pDown,BorderLayout.SOUTH);
pBottom.add(pRight,BorderLayout.EAST);
contentPane.add(pBottom,BorderLayout.SOUTH);
f.setSize(newDimension(320,256));
f.setResizable(false);
f.setVisible(true);
f.addWindowListener(newWindowAdapter()
{
publicvoidwindowClosing(WindowEvente)
{
System.exit(0);
}
}
);
}
/************************Java计算器计算方法区***************************/
publicvoidactionPerformed(ActionEvente)
{
Strings=e.getActionCommand();
if(s.equals("复制(C)"))
{
Stringtemp=tResult.getText().trim();
Board.replace(0,Board.length(),temp);
mPaste.setEnabled(true);
}
elseif(s.equals("粘贴(p)"))
{
tResult.setText(Board.toString());
}
elseif(s.equals("CE"))
{
//如果是CE则清除文本框
tResult.setText("0.");
}
elseif(s.equals("BackSpace"))
{
if(!tResult.getText().trim().equals("0."))
{
//如果文本框中有内容
if(str.length()!=1&&str.length()!=0)
{
tResult.setText(str.delete(str.length()-1,str.length()).toString());
}
else
{
tResult.setText("0.");
str.setLength(0);
}
}
op2=Double.parseDouble(tResult.getText().trim());
}
elseif(s.equals("C"))
{
//如果是C删除当前计算
tResult.setText("0.");
op1=op2=0;
str.replace(0,str.length(),"");
preOp=currentOp=0;
}
elseif(s.equals("MC"))
{
//如果是MC则清除缓冲区
Stringtemp="";
memory.replace(0,memory.length(),temp);
bM.setText("");
}
elseif(s.equals("MR"))
{
//如果按键为MR则恢复缓冲区的数到文本框
tResult.setText(memory.toString());
}
elseif(s.equals("MS"))
{
//如果按键为MS则将文本框的数存入缓冲区
Strings1=tResult.getText().trim();
memory.replace(0,memory.length(),s1);
bM.setText("M");
}
elseif(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
Stringtemp1=tResult.getText().trim();
doubledtemp=Double.parseDouble(temp1);
Stringtemp2=memory.toString();
dtemp+=Double.parseDouble(temp2);
temp1=String.valueOf(dtemp);
memory.replace(0,memory.length(),temp1);
}
elseif(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
Stringtemp=tResult.getText().trim();
doubledtemp=Double.parseDouble(temp);
tResult.setText(""+1/dtemp);
}
elseif(s.equals("sqrt"))
{
//如果按键为sqrt则将文本框中的内容求平方根
Stringtemp=tResult.getText().trim();
doubledtemp=Double.parseDouble(temp);
tResult.setText(""+Math.sqrt(dtemp));
}
elseif(s.equals("+"))
{
str.setLength(0);
if(currentOp==0)
{
preOp=currentOp=1;
op2=0;
tResult.setText(""+op1);
}
else
{
currentOp=preOp;
preOp=1;
switch(currentOp){
case1:
op1+=op2;
tResult.setText(""+op1);
break;
case2:
op1-=op2;
tResult.setText(""+op1);
break;
case3:
op1*=op2;
tResult.setText(""+op1);
break;
case4:
op1/=op2;
tResult.setText(""+op1);
break;
}
}
}
elseif(s.equals("-")){
str.setLength(0);
if(currentOp==0)
{
preOp=currentOp=2;//op1=op2;op2=0;
tResult.setText(""+op1);
}
else
{
currentOp=preOp;
preOp=2;
switch(currentOp){
case1:op1=op1+op2;tResult.setText(""+op1);break;
case2:op1=op1-op2;tResult.setText(""+op1);break;
case3:op1=op1*op2;tResult.setText(""+op1);break;
case4:op1=op1/op2;tResult.setText(""+op1);break;
}
}
}
elseif(s.equals("*"))//*
{
str.setLength(0);
if(currentOp==0)
{
preOp=currentOp=3;//op1=op2;op2=1;
tResult.setText(""+op1);//op1=op2;
}
else
{
currentOp=preOp;
preOp=3;
switch(currentOp){
case1:op1=op1+op2;tResult.setText(""+op1);break;
case2:op1=op1-op2;tResult.setText(""+op1);break;
case3:op1=op1*op2;tResult.setText(""+op1);break;
case4:op1=op1/op2;tResult.setText(""+op1);break;
}
}
}
elseif(s.equals("/"))///
{
str.setLength(0);
if(currentOp==0)
{
preOp=currentOp=4;//op2=1;
tResult.setText(""+op1);//op1=op2;
}
else
{
currentOp=preOp;
preOp=4;
switch(currentOp){
case1:op1=op1+op2;tResult.setText(""+op1);break;
case2:op1=op1-op2;tResult.setText(""+op1);break;
case3:op1=op1*op2;tResult.setText(""+op1);break;
case4:op1=op1/op2;tResult.setText(""+op1);break;
}
}
}
elseif(s.equals("="))//=
{
if(currentOp==0)
{
str.setLength(0);
tResult.setText(""+op2);
}
else
{
str.setLength(0);
currentOp=preOp;
switch(currentOp){
case1:op1=op1+op2;tResult.setText(""+op1);break;
case2:op1=op1-op2;tResult.setText(""+op1);break;
case3:op1=op1*op2;tResult.setText("&qu
3. java 写的计算器源代码只实现加减乘除四则运算即可
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.Vector;
public class calculator
{
String str1="0"; //运算数1 初值一定为0 为了程序的安全
String str2="0"; //运算数2
String fh="+"; //运算符
String jg="";//结果
//状态开关 重要
int k1=1;//开关1 用于选择输入方向 将要写入str2或 str2
int k2=1;//开关2 符号键 次数 k2>1说明进行的是2+3-9+8 这样的多符号运算
int k3=1;//开关3 str1 是否可以被清0 ==1时可以 !=1时不能被清0
int k4=1;//开关4 str2 同上
int k5=1;//开关5 控制小数点可否被录入 ==1时可以 !=1 输入的小数点被丢掉
JButton jicunqi; //寄存器 记录 是否连续按下符号键
Vector vt=new Vector(20,10);
JFrame frame=new JFrame("sunshine---计算器");
JTextField jg_TextField=new JTextField(jg,20);//20列
JButton clear_Button=new JButton("清除");
JButton button0=new JButton("0");
JButton button1=new JButton("1");
JButton button2=new JButton("2");
JButton button3=new JButton("3");
JButton button4=new JButton("4");
JButton button5=new JButton("5");
JButton button6=new JButton("6");
JButton button7=new JButton("7");
JButton button8=new JButton("8");
JButton button9=new JButton("9");
JButton button_Dian=new JButton(".");
JButton button_jia=new JButton("+");
JButton button_jian=new JButton("-");
JButton button_cheng=new JButton("*");
JButton button_chu=new JButton("/");
JButton button_dy=new JButton("=");
public static void main(String[] args)
{
calculator calculator=new calculator();
}
calculator()
{
jg_TextField.setHorizontalAlignment(JTextField.RIGHT );//文本框 右对齐
JPanel pan=new JPanel();
pan.setLayout(new GridLayout(4,4,5,5));//四行四列 边距为5像素
pan.add(button7);
pan.add(button8);
pan.add(button9);
pan.add(button_chu);
pan.add(button4);
pan.add(button5);
pan.add(button6);
pan.add(button_cheng);
pan.add(button1);
pan.add(button2);
pan.add(button3);
pan.add(button_jian);
pan.add(button0);
pan.add(button_Dian);
pan.add(button_dy);
pan.add(button_jia);
pan.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));//pan对象的边距
JPanel pan2=new JPanel();
pan2.add(jg_TextField);
JPanel pan3=new JPanel(); //为什么要 多此一句呢？ 因为我不会设置 按钮的大小
pan3.setLayout(new FlowLayout());
pan3.add(clear_Button);
//clear_Button.setSize(10,10);//设置清零按钮的大小 吗的 不好使 ！！
frame.setLocation(300, 200); //主窗口 出现在位置
frame.setResizable(false); //不能调大小
frame.getContentPane().setLayout(new BorderLayout());
frame.getContentPane().add(pan2,BorderLayout.NORTH);
frame.getContentPane().add(pan,BorderLayout.CENTER);
frame.getContentPane().add(pan3,BorderLayout.SOUTH);
frame.pack();
frame.setVisible(true);
//以上是 控件 和 布局
//下面是事件处理 程 序
//--------------- 数 字 键 ----------------
class JianTing implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String ss=((JButton)e.getSource()).getText();
jicunqi=(JButton)e.getSource();
vt.add(jicunqi);
if (k1==1)
{
if(k3==1)
{
str1="";
k5=1;//还原开关k5状态
}
str1=str1+ss;
//k2=1;
k3=k3+1;
//System.out.println(str1);
jg_TextField.setText(str1);//显示
}
else if(k1==2)
{
if (k4==1)
{
str2="";
k5=1; //还原开关k5状态
}
str2=str2+ss;
//k2=2;
k4=k4+1;
///////////////测试////////////////
jg_TextField.setText(str2);
}
}
}
//－－－－－－－－符 号－－－－－－－－－－－
class JianTing_fh implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String ss2=((JButton)e.getSource()).getText();
jicunqi=(JButton)e.getSource();
vt.add(jicunqi);
if(k2==1)
{
k1=2;//开关 k1 为1时,向数1写 为2时，向数2写
k5=1;
fh=ss2;
k2=k2+1;//按符号键的次数
}
else
{
int a=vt.size();
JButton c=(JButton)vt.get(a-2); if(!(c.getText().equals("+"))&&!(c.getText().equals("-"))&&!(c.getText().equals("*"))&&!(c.getText().equals("/")))
{
yuns();
str1=jg;
k1=2;//开关 k1 为1时,向数1写 为2时，向数2写
k5=1;
k4=1;
fh=ss2;
} k2=k2+1;
}
}
}
//－－－－－－－－清除－－－－－－－
class JianTing_clear implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jicunqi=(JButton)e.getSource();
vt.add(jicunqi);
k5=1;
k2=1;
k1=1;
k3=1;
k4=1;
str1="0";
str2="0";
fh="";
jg="";
jg_TextField.setText(jg);
vt.clear();
}
}
//----------------等 于 ---------------------
class JianTing_dy implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jicunqi=(JButton)e.getSource();
vt.add(jicunqi);
yuns();
k1=1; //还原开关k1状态
//str1=jg;
k2=1;
k3=1;//还原开关k3状态
k4=1; //还原开关k4状态
str1=jg; //为7+5=12 +5=17 这种计算做准备
}
}
//----------------小数点 ---------------------
class JianTing_xiaos implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jicunqi=(JButton)e.getSource();
vt.add(jicunqi);
if(k5==1)
{
String ss2=((JButton)e.getSource()).getText();
if (k1==1)
{
if(k3==1)
{
str1="";
k5=1; //还原开关k5状态
}
str1=str1+ss2;
//k2=1;
k3=k3+1;
//System.out.println(str1);
jg_TextField.setText(str1);//显示
}
else if(k1==2)
{
if (k4==1)
{
str2="";
k5=1; //还原开关k5状态
}
str2=str2+ss2;
//k2=2;
k4=k4+1;
///////////////测试////////////////
jg_TextField.setText(str2);
}
}
k5=k5+1;
}
}
//注册 监听器
JianTing_dy jt_dy=new JianTing_dy();
JianTing jt= new JianTing();//临听数字键
JianTing_fh jt_fh= new JianTing_fh();//临 听符 号键
JianTing_clear jt_c=new JianTing_clear(); //清除键
JianTing_xiaos jt_xs=new JianTing_xiaos();// 小数点 键
button7.addActionListener(jt);
button8.addActionListener(jt);
button9.addActionListener(jt);
button_chu.addActionListener(jt_fh);
button4.addActionListener(jt);
button5.addActionListener(jt);
button6.addActionListener(jt);
button_cheng.addActionListener(jt_fh);
button1.addActionListener(jt);
button2.addActionListener(jt);
button3.addActionListener(jt);
button_jian.addActionListener(jt_fh);
button0.addActionListener(jt);
button_Dian.addActionListener(jt_xs);
button_dy.addActionListener(jt_dy);
button_jia.addActionListener(jt_fh);
clear_Button.addActionListener(jt_c);
//关闭事件处理程序
frame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
//---------------计 算------------------
public void yuns()
{
double a2,b2;//运算数1,2
String c=fh;// 运算符
double jg2=0 ;//结果
if (c.equals(""))
{
//System.out.println("请输入运算符");
jg_TextField.setText("请输入运算符");
}
else
{
System.out.println("str1:"+str1);//调试时 使 用
System.out.println("str2:"+str2);//调试时 使 用
System.out.println("运算符:"+fh);//调试时 使 用
if (str1.equals(".")) //字符串 "." 转换成double型数据时 会出错 所以手工转
str1="0.0";
if (str2.equals("."))
str2="0.0";
a2=Double.valueOf(str1).doubleValue();
b2=Double.valueOf(str2).doubleValue();
System.out.println("double型的a2："+a2); //调试时 使 用
System.out.println("double型的b2："+b2); //调试时 使 用
if (c.equals("+"))
{
jg2=a2+b2;
}
if (c.equals("-"))
{
jg2=a2-b2;
}
if (c.equals("*"))
{
jg2=a2*b2;
}
if (c.equals("/"))
{
if(b2==0)
{
jg2=0;//0000000000000 by 0 cu!
}
else
{
jg2=a2/b2;
}
}
System.out.println("double型a2"+fh+"b2结果："+jg2);
System.out.println();
jg=((new Double(jg2)).toString());
jg_TextField.setText(jg);
}
}
}
4. 编写一个JAVA计算器程序
import java.awt.*;
import java.awt.event.*;
import java.lang.*;
import javax.swing.*;
public class Counter extends Frame
{
//声明三个面板的布局
GridLayout gl1,gl2,gl3;
Panel p0,p1,p2,p3;
JTextField tf1;
TextField tf2;
Button b0,b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,b15,b16,b17,b18,b19,b20,b21,b22,b23,b24,b25,b26;
StringBuffer str;//显示屏所显示的字符串
double x,y;//x和y都是运算数
int z;//Z表示单击了那一个运算符.0表示"+",1表示"-",2表示"*",3表示"/"
static double m;//记忆的数字
public Counter()
{
gl1=new GridLayout(1,4,10,0);//实例化三个面板的布局
gl2=new GridLayout(4,1,0,15);
gl3=new GridLayout(4,5,10,15);
tf1=new JTextField(27);//显示屏
tf1.setHorizontalAlignment(JTextField.RIGHT);
tf1.setEnabled(false);
tf1.setText("0");
tf2=new TextField(10);//显示记忆的索引值
tf2.setEditable(false);
//实例化所有按钮、设置其前景色并注册监听器
b0=new Button("Backspace");
b0.setForeground(Color.red);
b0.addActionListener(new Bt());
b1=new Button("CE");
b1.setForeground(Color.red);
b1.addActionListener(new Bt());
b2=new Button("C");
b2.setForeground(Color.red);
b2.addActionListener(new Bt());
b3=new Button("MC");
b3.setForeground(Color.red);
b3.addActionListener(new Bt());
b4=new Button("MR");
b4.setForeground(Color.red);
b4.addActionListener(new Bt());
b5=new Button("MS");
b5.setForeground(Color.red);
b5.addActionListener(new Bt());
b6=new Button("M+");
b6.setForeground(Color.red);
b6.addActionListener(new Bt());
b7=new Button("7");
b7.setForeground(Color.blue);
b7.addActionListener(new Bt());
b8=new Button("8");
b8.setForeground(Color.blue);
b8.addActionListener(new Bt());
b9=new Button("9");
b9.setForeground(Color.blue);
b9.addActionListener(new Bt());
b10=new Button("/");
b10.setForeground(Color.red);
b10.addActionListener(new Bt());
b11=new Button("sqrt");
b11.setForeground(Color.blue);
b11.addActionListener(new Bt());
b12=new Button("4");
b12.setForeground(Color.blue);
b12.addActionListener(new Bt());
b13=new Button("5");
b13.setForeground(Color.blue);
b13.addActionListener(new Bt());
b14=new Button("6");
b14.setForeground(Color.blue);
b14.addActionListener(new Bt());
b15=new Button("*");
b15.setForeground(Color.red);
b15.addActionListener(new Bt());
b16=new Button("%");
b16.setForeground(Color.blue);
b16.addActionListener(new Bt());
b17=new Button("1");
b17.setForeground(Color.blue);
b17.addActionListener(new Bt());
b18=new Button("2");
b18.setForeground(Color.blue);
b18.addActionListener(new Bt());
b19=new Button("3");
b19.setForeground(Color.blue);
b19.addActionListener(new Bt());
b20=new Button("-");
b20.setForeground(Color.red);
b20.addActionListener(new Bt());
b21=new Button("1/X");
b21.setForeground(Color.blue);
b21.addActionListener(new Bt());
b22=new Button("0");
b22.setForeground(Color.blue);
b22.addActionListener(new Bt());
b23=new Button("+/-");
b23.setForeground(Color.blue);
b23.addActionListener(new Bt());
b24=new Button(".");
b24.setForeground(Color.blue);
b24.addActionListener(new Bt());
b25=new Button("+");
b25.setForeground(Color.red);
b25.addActionListener(new Bt());
b26=new Button("=");
b26.setForeground(Color.red);
b26.addActionListener(new Bt());
//实例化四个面板
p0=new Panel();
p1=new Panel();
p2=new Panel();
p3=new Panel();
//创建一个空字符串缓冲区
str=new StringBuffer();
//添加面板p0中的组件和设置其在框架中的位置和大小
p0.add(tf1);
p0.setBounds(10,25,300,40);
//添加面板p1中的组件和设置其在框架中的位置和大小
p1.setLayout(gl1);
p1.add(tf2);
p1.add(b0);
p1.add(b1);
p1.add(b2);
p1.setBounds(10,65,300,25);
//添加面板p2中的组件并设置其的框架中的位置和大小
p2.setLayout(gl2);
p2.add(b3);
p2.add(b4);
p2.add(b5);
p2.add(b6);
p2.setBounds(10,110,40,150);
//添加面板p3中的组件并设置其在框架中的位置和大小
p3.setLayout(gl3);//设置p3的布局
p3.add(b7);
p3.add(b8);
p3.add(b9);
p3.add(b10);
p3.add(b11);
p3.add(b12);
p3.add(b13);
p3.add(b14);
p3.add(b15);
p3.add(b16);
p3.add(b17);
p3.add(b18);
p3.add(b19);
p3.add(b20);
p3.add(b21);
p3.add(b22);
p3.add(b23);
p3.add(b24);
p3.add(b25);
p3.add(b26);
p3.setBounds(60,110,250,150);
//设置框架中的布局为空布局并添加4个面板
setLayout(null);
add(p0);
add(p1);
add(p2);
add(p3);
setResizable(false);//禁止调整框架的大小
//匿名类关闭窗口
addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e1)
{
System.exit(0);
}
});
setBackground(Color.lightGray);
setBounds(100,100,320,280);
setVisible(true);
}
//构造监听器
class Bt implements ActionListener
{
public void actionPerformed(ActionEvent e2)
{
try{
if(e2.getSource()==b1)//选择"CE"清零
{
tf1.setText("0");//把显示屏清零
str.setLength(0);//清空字符串缓冲区以准备接收新的输入运算数
}
else if(e2.getSource()==b2)//选择"C"清零
{
tf1.setText("0");//把显示屏清零
str.setLength(0);
}
else if(e2.getSource()==b23)//单击"+/-"选择输入的运算数是正数还是负数
{
x=Double.parseDouble(tf1.getText().trim());
tf1.setText(""+(-x));
}
else if(e2.getSource()==b25)//单击加号按钮获得x的值和z的值并清空y的值
{
x=Double.parseDouble(tf1.getText().trim());
str.setLength(0);//清空缓冲区以便接收新的另一个运算数
y=0d;
z=0;
}
else if(e2.getSource()==b20)//单击减号按钮获得x的值和z的值并清空y的值
{
x=Double.parseDouble(tf1.getText().trim());
str.setLength(0);
y=0d;
z=1;
}
else if(e2.getSource()==b15)//单击乘号按钮获得x的值和z的值并清空y的值
{
x=Double.parseDouble(tf1.getText().trim());
str.setLength(0);
y=0d;
z=2;
}
else if(e2.getSource()==b10)//单击除号按钮获得x的值和z的值并空y的值
{
x=Double.parseDouble(tf1.getText().trim());
str.setLength(0);
y=0d;
z=3;
}
else if(e2.getSource()==b26)//单击等号按钮输出计算结果
{
str.setLength(0);
switch(z)
{
case 0 : tf1.setText(""+(x+y));break;
case 1 : tf1.setText(""+(x-y));break;
case 2 : tf1.setText(""+(x*y));break;
case 3 : tf1.setText(""+(x/y));break;
}
}
else if(e2.getSource()==b24)//单击"."按钮输入小数
{
if(tf1.getText().trim().indexOf(′.′)!=-1)//判断字符串中是否已经包含了小数点
{
}
else//如果没数点有小
{
if(tf1.getText().trim().equals("0"))//如果初时显示为0
{
str.setLength(0);
tf1.setText((str.append("0"+e2.getActionCommand())).toString());
}
else if(tf1.getText().trim().equals(""))//如果初时显示为空则不做任何操作
{
}
else
{
tf1.setText(str.append(e2.getActionCommand()).toString());
}
}
y=0d;
}
else if(e2.getSource()==b11)//求平方根
{
x=Double.parseDouble(tf1.getText().trim());
tf1.setText("数字格式异常");
if(x<0)
tf1.setText("负数没有平方根");
else
tf1.setText(""+Math.sqrt(x));
str.setLength(0);
y=0d;
}
else if(e2.getSource()==b16)//单击了"%"按钮
{
x=Double.parseDouble(tf1.getText().trim());
tf1.setText(""+(0.01*x));
str.setLength(0);
y=0d;
}
else if(e2.getSource()==b21)//单击了"1/X"按钮
{
x=Double.parseDouble(tf1.getText().trim());
if(x==0)
{
tf1.setText("除数不能为零");
}
else
{
tf1.setText(""+(1/x));
}
str.setLength(0);
y=0d;
}
else if(e2.getSource()==b3)//MC为清除内存
{
m=0d;
tf2.setText("");
str.setLength(0);
}
else if(e2.getSource()==b4)//MR为重新调用存储的数据
{
if(tf2.getText().trim()!="")//有记忆数字
{
tf1.setText(""+m);
}
}
else if(e2.getSource()==b5)//MS为存储显示的数据
{
m=Double.parseDouble(tf1.getText().trim());
tf2.setText("M");
tf1.setText("0");
str.setLength(0);
}
else if(e2.getSource()==b6)//M+为将显示的数字与已经存储的数据相加要查看新的数字单击MR
{
m=m+Double.parseDouble(tf1.getText().trim());
}
else//选择的是其他的按钮
{
if(e2.getSource()==b22)//如果选择的是"0"这个数字键
{
if(tf1.getText().trim().equals("0"))//如果显示屏显示的为零不做操作
{
}
else
{
tf1.setText(str.append(e2.getActionCommand()).toString());
y=Double.parseDouble(tf1.getText().trim());
}
}
else if(e2.getSource()==b0)//选择的是“BackSpace”按钮
{
if(!tf1.getText().trim().equals("0"))//如果显示屏显示的不是零
{
if(str.length()!=1)
{
tf1.setText(str.delete(str.length()-1,str.length()).toString());//可能抛出字符串越界异常
}
else
{
tf1.setText("0");
str.setLength(0);
}
}
y=Double.parseDouble(tf1.getText().trim());
}
else//其他的数字键
{
tf1.setText(str.append(e2.getActionCommand()).toString());
y=Double.parseDouble(tf1.getText().trim());
}
}
}
catch(NumberFormatException e){
tf1.setText("数字格式异常");
}
catch( e){
tf1.setText("字符串索引越界");
}
}
}
public static void main(String args[])
{
new Counter();
}
}
这个是别人写的。。。
回答者： ざぉを - 江湖新秀 四级 4-17 13:51
这段代码对你有帮助
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。MyCalculator 继承于 JFrame，是计算器的界面
*/
public class MyCalculator 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 MyCalculator(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());
MyCalculator frame = new MyCalculator("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);
}
}