計算器代碼java

『壹』 鐢╦ava緙栧緱璁＄畻鍣ㄧ▼搴忚蔣浠跺拰婧愪唬鐮

java璁＄畻鍣ㄦ簮紼嬪簭
java璁＄畻鍣

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
class calculation extends JFrame
{public calculation() /*鏋勯犳柟娉*/
{super("璁℃暟鍣");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
initTextPanel(); /*鏂囨湰妗*/
initControlPanel(); /*鎺у埗閿*/
initKeyPanel(); /*鏁板瓧鍜岃繍綆楃*/
Container pane = getContentPane();
pane.setLayout(new BorderLayout());
pane.add(TextPanel,BorderLayout.NORTH);
pane.add(ControlPanel,BorderLayout.CENTER);
pane.add(KeyPanel,BorderLayout.SOUTH);
pack();
try
{UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
}
catch(Exception ex)
{;} /璁╅敭*璁劇疆Windons瑙傛劅*/
SwingUtilities.updateComponentTreeUI(this);
setResizable(false);
setVisible(true);
}

private void initTextPanel() /*璁劇疆鏂囨湰妗*/
{ TextPanel=new JPanel();
TextPanel.setLayout(new FlowLayout());
Resultarea =new JTextField("0",25);
Resultarea.setEditable(false); /*璁劇疆涓嶅彲緙栬緫*/
Color color=Color.white;
Resultarea.setBackground(color); /*棰滆壊*/
Resultarea.setHorizontalAlignment(JTextField.RIGHT); /*璁炬墥婊戞壆緗鏄劇ず浣嶇疆*/
TextPanel.add(Resultarea);
}

private void initControlPanel() /*璁劇疆鎺у埗閿鏄ョ伓*/
{ControlPanel=new JPanel();
ControlPanel.setLayout(new GridLayout(1,3,4,4));
JButton b1=new JButton("Backspace"); /*Backspace閿*/
b1.setFont(font1);
b1.addActionListener(new ActionListener()
{public void actionPerformed(ActionEvent e)
{String s1=Resultarea.getText();
int l=s1.length();
Resultarea.setText(s1.substring(0 ,l-1));
}
});

ControlPanel.add(b1);
JButton b2=new JButton("CE"); /*CE閿*/
b2.setFont(font1);
b2.addActionListener(new ActionListener()
{public void actionPerformed(ActionEvent e)
{Resultarea.setText("0");
isNew=true;
}
});
ControlPanel.add(b2);

JButton b3=new JButton("C"); /*C閿*/
b3.setFont(font1);
b3.addActionListener(new ActionListener()
{public void actionPerformed(ActionEvent e)
{Resultarea.setText("0");
pnum="";
operation="";
isNew=true;
}
});
ControlPanel.add(b3);
}

private void initKeyPanel() /*璁劇疆鏁板瓧閿鍜岃繍綆楃﹂敭*/
{String key[] = {"7","8","9","/","sqrt","4","5","6","*","%","1","2","3","-","1/x","0","+/-",".","+","="};
KeyPanel = new JPanel();
KeyPanel.setLayout(new GridLayout(4,5,4,4));
for(int i=0;i<20;i++)
{String label = key[i];
JButton b = new JButton(label);
b.setActionCommand(key[i]);
b.setFont(font2);
KeyPanel.add(b);
b.addActionListener(new ActionListener() /*鏃犲悕鐩戝惉鍣*/
{public void actionPerformed(ActionEvent e)
{Key_actionPerformed(e);
}
});
}
}
public void Key_actionPerformed(ActionEvent e) /*鏁板瓧閿鍜岃繍綆楃﹂敭鏃犲悕鐩戝惉鍣*/
{String s=(e.getActionCommand());
String st=Resultarea.getText();
if(s.equals("0")) /*杈撳叆鏁頒負0*/
{if(st.equals("0"))
return;
else
{if(!isNew)
Resultarea.setText(st+"0");
else
Resultarea.setText("0");
}
isNew=false;
return;
}

if(s.equals("+/-")) /*杈撳叆鏁頒負+/-*/
{double k=Double.parseDouble(st);
{if(k!=0)
display(-k);

}
return;
}

if(s.equals("1")||s.equals("2")||s.equals("3")||s.equals("4")||s.equals("5")||s.equals("6")||s.equals("7")||s.equals("8")||s.equals("9")) /*杈撳叆1-9*/
{if(!isNew)
Resultarea.setText(st+s);
else
{ Resultarea.setText(s);
isNew=false;
}
return;
}

if(s.equals(".")) /*杈撳叆灝忔暟鐐*/
{if(Resultarea.getText().indexOf(".")==-1) /*涓嶅瓨鍦ㄥ皬鏁扮偣*/
{if(isNew)
{Resultarea.setText("0.");
isNew=false;
}
else
Resultarea.setText(st+".");
}
return;
}

isNew=true; /*鎸変笅榪愮畻絎︼紝杈撳叆鏂扮殑鏁*/
if(s.equals("="))
{compute(s);
operation="";
}
else
{if(s.equals("+")||s.equals("-")||s.equals("*")||s.equals("/")) /*浜岀洰榪愮畻絎﹀彿*/
{if(operation.equals(""))
{pnum=Resultarea.getText();
operation=s;
}
else
compute(s);
}
else /*涓鐩榪愮畻*/
{Count count1=new Count(Double.parseDouble(st));
if(s.equals("sqrt"))
{
display(count1.sqrt());

}
else
{if(s.equals("1/x"))
{if(st.equals("0"))
{Resultarea.setText("闄ゆ暟涓嶈兘涓0.");
operation="";
pnum="";
}
else
display(count1.reciprocal()); /*奼傚掓暟*/
}
else
display(Double.parseDouble(st)/100); /*杈撳叆%錛屼嬌褰撳墠鏄劇ず鐨勫奸櫎浜100*/
}
}
}
}

private void compute(String s)
{if(s.equals("="))
{if(operation.equals(""))
return;
}
double data1=Double.parseDouble(pnum);
double data2=Double.parseDouble(Resultarea.getText());
Count count2=new Count(data1,data2); /*鍔犲噺涔橀櫎璁＄畻*/
if(operation.equals("+"))
display((count2.plus()));
else
{if(operation.equals("-"))
display((count2.minus()));
else
{if(operation.equals("*"))
display((count2.multiply()));
else
if(operation.equals("/"))
{if(data2==0)
{Resultarea.setText("闄ゆ暟涓嶈兘涓0");
operation="";
pnum="";
return;
}
else
display((count2.divide()));
}
}
}
operation=""; /*絎﹀彿涓哄綋鍓嶇*/
pnum=Resultarea.getText();/*榪愮畻鏁頒負褰撳墠鏂囨湰鏁*/
}

public void display(double result) /*鏄劇ず杈撳嚭鏂規硶*/
{int a=(int)result;
if(a==result)
Resultarea.setText(String.valueOf(a));
else
Resultarea.setText(String.valueOf(result));
if(Resultarea.getText().equals("NaN"))
Resultarea.setText("杈撳叆鍑芥暟鏃犳晥");
}

private JPanel TextPanel; /*鏂囨湰妗嗘夋澘*/
private JTextField Resultarea; /*鏂囨湰妗*/
private JPanel ControlPanel; /*鎺у埗閿閿闈㈡澘*/
private JPanel KeyPanel; /*鏁板瓧閿鍜岃繍綆楃﹂敭闈㈡澘*/
private Font font1=new Font("Dialog",0, 10); /*鎺у埗閿瀛椾綋*/
private Font font2 = new Font("Dialog",0,10); /*鏁板瓧閿鍜岀﹀彿閿瀛椾綋*/
private String pnum=""; /*鍓嶆搷浣滄暟*/
private boolean isNew=true; /*鎺у埗鏄鍚︽槸鏂版暟*/
private String operation=""; /*榪愮畻絎*/
}

class tester /*嫻嬭瘯綾*/
{
public static void main(String[] args)
{
new calculation();
}
}

『貳』 用JAVA編寫的科學計算器源代碼

以下是一個簡單的用Java編寫的科學計算器的源代碼示例：

java

import java.util.Scanner;

public class ScientificCalculator {

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

System.out.println("Welcome to the Scientific Calculator!");

System.out.println("Enter 'add', 'subtract', 'multiply', 'divide', 'sin', 'cos', 'tan', 'log', 'exp', 'sqrt', or 'quit' to exit.");

while (true) {

System.out.print("Enter operation (e.g., add 2 3): ");

String operation = scanner.nextLine();

if (operation.equalsIgnoreCase("quit")) {

break;

}

String[] parts = operation.split(" ");

double num1 = Double.parseDouble(parts[1]);

double num2 = Double.parseDouble(parts[2]);

switch (parts[0].toLowerCase()) {

case "add":

System.out.println(num1 + " + " + num2 + " = " + (num1 + num2));

break;

case "subtract":

System.out.println(num1 + " - " + num2 + " = " + (num1 - num2));

break;

case "multiply":

System.out.println(num1 + " * " + num2 + " = " + (num1 * num2));

break;

case "divide":

if (num2 != 0) {

System.out.println(num1 + " / " + num2 + " = " + (num1 / num2));

} else {

System.out.println("Error: Division by zero is not allowed.");

}

break;

case "sin":

System.out.println("sin(" + num1 + ") = " + Math.sin(Math.toRadians(num1)));

break;

case "cos":

System.out.println("cos(" + num1 + ") = " + Math.cos(Math.toRadians(num1)));

break;

case "tan":

System.out.println("tan(" + num1 + ") = " + Math.tan(Math.toRadians(num1)));

break;

case "log":

System.out.println("log(" + num1 + ") = " + Math.log10(num1));

break;

case "exp":

System.out.println("exp(" + num1 + ") = " + Math.exp(num1));

break;

case "sqrt":

if (num1 >= 0) {

System.out.println("sqrt(" + num1 + ") = " + Math.sqrt(num1));

} else {

System.out.println("Error: Cannot calculate the square root of a negative number.");

}

break;

default:

System.out.println("Error: Invalid operation.");

break;

}

}

scanner.close();

System.out.println("Goodbye!");

}

}

這個科學計算器支持基本的四則運算（加、減、乘、除）以及一些科學運算（正弦、餘弦、正切、對數、指數和平方根）。用戶可以通過輸入相應的操作和兩個數字來執行計算。例如，輸入“add 2 3”將計算2加3的結果。

代碼首先導入了`Scanner`類，用於從用戶處獲取輸入。然後，在`main`方法中，創建了一個`Scanner`對象，用於讀取用戶的輸入。程序通過一個無限循環來持續接收用戶的輸入，直到用戶輸入“quit”為止。

在循環中，程序首先提示用戶輸入一個操作，然後讀取用戶的輸入並將其分割為多個部分。接著，程序將第二個和第三個部分轉換為`double`類型的數字，並根據第一個部分（即操作）執行相應的計算。

程序使用`switch`語句來根據用戶輸入的操作執行相應的計算。對於基本的四則運算，程序直接執行相應的計算並輸出結果。對於科學運算，程序使用了Java的`Math`類中的相應方法。例如，對於正弦運算，程序使用了`Math.sin`方法，並將角度轉換為弧度作為參數傳遞給它。

如果用戶輸入了無效的操作或無效

『叄』 java編一個計算器的代碼

界面漂亮堪御尺比系統自帶穗拆兆計算器，功能完美加減乘除開平方等等猜租全部具備，還有清零按鈕，小數點的使用，連加連乘功能完全參考系統官方計算器經過長期調試改進而成，馬上拷貝代碼拿去試試看吧，絕不後悔！

代碼如下：

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("編輯");
menuFile2.setText("查看");
menuFile3.setText("幫助");

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("計算器");
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;i<20;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);
}
}

---------------------------------------------------------------------------
=============《按你要求特意後改過的最簡單功能的代碼如下》========================

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("計算器");
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;i<16;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_輝祝您愉快！

『肆』 java 寫的計算器源代碼只實現加減乘除四則運算即可

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.Vector;
public class calculator
{
String str1="0"; //運算數1 初值一定為0 為了程序的安全
String str2="0"; //運算數2
String fh="+"; //運算符
String jg="";//結果
//狀態開關 重要
int k1=1;//開關1 用於選擇輸入方向 將要寫入str2或 str2
int k2=1;//開關2 符號鍵 次數 k2>1說明進行的是2+3-9+8 這樣的多符號運算
int k3=1;//開關3 str1 是否可以被清0 ==1時可以 !=1時不能被清0
int k4=1;//開關4 str2 同上
int k5=1;//開關5 控制小數點可否被錄入 ==1時可以 !=1 輸入的小數點被丟掉
JButton jicunqi; //寄存器 記錄 是否連續按下符號鍵
Vector vt=new Vector(20,10);
JFrame frame=new JFrame("sunshine---計算器");
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 右對齊
JPanel pan=new JPanel();
pan.setLayout(new GridLayout(4,4,5,5));//四行四列 邊距為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對象的邊距
JPanel pan2=new JPanel();
pan2.add(jg_TextField);
JPanel pan3=new JPanel(); //為什麼要 多此一句呢？ 因為我不會設置 按鈕的大小
pan3.setLayout(new FlowLayout());
pan3.add(clear_Button);
//clear_Button.setSize(10,10);//設置清零按鈕的大小 嗎的 不好使 ！！
frame.setLocation(300, 200); //主窗口 出現在位置
frame.setResizable(false); //不能調大小
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 控制項 和 布局
//下面是事件處理 程 序
//--------------- 數 字 鍵 ----------------
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;//還原開關k5狀態
}
str1=str1+ss;
//k2=1;
k3=k3+1;
//System.out.println(str1);
jg_TextField.setText(str1);//顯示
}
else if(k1==2)
{
if (k4==1)
{
str2="";
k5=1; //還原開關k5狀態
}
str2=str2+ss;
//k2=2;
k4=k4+1;
///////////////測試////////////////
jg_TextField.setText(str2);
}
}
}

//－－－－－－－－符 號－－－－－－－－－－－
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;//開關 k1 為1時,向數1寫 為2時，向數2寫
k5=1;
fh=ss2;
k2=k2+1;//按符號鍵的次數
}
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;//開關 k1 為1時,向數1寫 為2時，向數2寫
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 於 ---------------------
class JianTing_dy implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
jicunqi=(JButton)e.getSource();
vt.add(jicunqi);
yuns();
k1=1; //還原開關k1狀態
//str1=jg;
k2=1;
k3=1;//還原開關k3狀態
k4=1; //還原開關k4狀態
str1=jg; //為7+5=12 +5=17 這種計算做准備
}
}
//----------------小數點 ---------------------
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; //還原開關k5狀態
}
str1=str1+ss2;
//k2=1;
k3=k3+1;
//System.out.println(str1);
jg_TextField.setText(str1);//顯示
}
else if(k1==2)
{
if (k4==1)
{
str2="";
k5=1; //還原開關k5狀態
}
str2=str2+ss2;
//k2=2;
k4=k4+1;
///////////////測試////////////////
jg_TextField.setText(str2);
}
}
k5=k5+1;
}
}
//注冊 監聽器
JianTing_dy jt_dy=new JianTing_dy();
JianTing jt= new JianTing();//臨聽數字鍵
JianTing_fh jt_fh= new JianTing_fh();//臨 聽符 號鍵
JianTing_clear jt_c=new JianTing_clear(); //清除鍵
JianTing_xiaos jt_xs=new JianTing_xiaos();// 小數點 鍵
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);
//關閉事件處理程序
frame.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
//---------------計 算------------------
public void yuns()
{
double a2,b2;//運算數1,2
String c=fh;// 運算符
double jg2=0 ;//結果
if (c.equals(""))
{
//System.out.println("請輸入運算符");
jg_TextField.setText("請輸入運算符");
}
else
{
System.out.println("str1:"+str1);//調試時 使 用
System.out.println("str2:"+str2);//調試時 使 用
System.out.println("運算符:"+fh);//調試時 使 用
if (str1.equals(".")) //字元串 "." 轉換成double型數據時 會出錯 所以手工轉
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); //調試時 使 用
System.out.println("double型的b2："+b2); //調試時 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結果："+jg2);
System.out.println();
jg=((new Double(jg2)).toString());
jg_TextField.setText(jg);
}
}
}

『伍』 java課程設計題目及代碼是什麼

java課程設計題目及代碼分別是：

1、題目：計算器。設計內容是設計一個圖形界面（GUI）的計算器應用程序，完成簡單的算術運算。

設計要求是設計的計算器應用程序可以完成家法、減法、乘法、除法和取余運算。且有小數點、正負號、求倒數、退格和清零功能。

2、代碼：

數字按鈕NumberButton類如下：

import java.awt.

import java.awt.event.

import javax.swing.

public class NumberButton extends Button.

{

int number.

public NumberButton(int number).

{

super(""+number).

this.number=number.

setForeground(Color.blue).

}

public int getNumber().

{

return number;

}

}

其它java課程設計題目及代碼是：

題目：華容道。編寫一個按鈕的子類，使用該子類創建的對象代表華容道中的人物。通過焦點事件控制人物顏色，當人物獲得焦點時顏色為藍色，當失去焦點時顏色為灰色。

通過鍵盤事件和滑鼠事件來實現曹操、關羽等人物的移動。當人物上發生滑鼠事件或鍵盤事件時，如果滑鼠指針的位置是在人物的下方（也就是組件的下半部分）或按下鍵盤的「↓「鍵，該人物向下移動。向左、向右和向上的移動原理類似。

代碼是：

String name[]={"曹操","關羽","張","劉","馬","許","兵","兵","兵","兵"}.

for(int i=0;i<name.length;i++).

{

person[i]=new Person(i,name[i]).

person[i].addKeyListener(this).

person[i].addMouseListener(this).

// person[i].addFocusListener(new Person).

add(person[i]).

}

person[0].setBounds(104,54,100,100).

person[1].setBounds(104,154,100,50).

person[2].setBounds(54,154,50,100).

person[3].setBounds(204,154,50,100).

person[4].setBounds(54,54,50,100).

person[5].setBounds(204,54,50,100);

person[6].setBounds(54,254,50,50);

person[7].setBounds(204,254,50,50);

person[8].setBounds(104,204,50,50);

person[9].setBounds(154,204,50,50);