java代碼科學計算器代碼

1. java編一個計算器的代碼

界面漂亮堪比系統自帶計算器，功能完美加減乘除開平方等等全部具備，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！

2. 用JAVA編寫的科學計算器源代碼

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
class Counter extends WindowAdapter
{
static JFrame f=new JFrame("計算器");
static JTextField text1=new JTextField("0.");
static String source="";
static String cal="";
static String object="";
static boolean flag=false;
static boolean flag1=true;
static boolean flag2=false;
public void init()
{
try
{
Container c=f.getContentPane();
JPanel pan1=new JPanel();
JButton b1=new JButton("1");
JButton b2=new JButton("2");
JButton b3=new JButton("3");
JButton b4=new JButton("4");
JButton b5=new JButton("5");
JButton b6=new JButton("6");
JButton b7=new JButton("7");
JButton b8=new JButton("8");
JButton b9=new JButton("9");
JButton b0=new JButton("0");
JButton b11=new JButton("+");
JButton b12=new JButton("-");
JButton b13=new JButton("*");
JButton b14=new JButton("/");
JButton b15=new JButton(".");
JButton b16=new JButton("=");
JButton bclar=new JButton("清零");
text1.setHorizontalAlignment(JTextField.RIGHT);
c.add(text1,"North");
c.add(pan1);
A aa=new A();
Result re=new Result();
Opertion op=new Opertion();
Clar cl=new Clar();
b1.addActionListener(aa);
b2.addActionListener(aa);
b3.addActionListener(aa);
b4.addActionListener(aa);
b5.addActionListener(aa);
b6.addActionListener(aa);
b7.addActionListener(aa);
b8.addActionListener(aa);
b9.addActionListener(aa);
b0.addActionListener(aa);
b11.addActionListener(op);
b12.addActionListener(op);
b13.addActionListener(op);
b14.addActionListener(op);
b16.addActionListener(re);
b15.addActionListener(aa);
bclar.addActionListener(cl);
pan1.add(b1);
pan1.add(b2);
pan1.add(b3);
pan1.add(b11);
pan1.add(b4);
pan1.add(b5);
pan1.add(b6);
pan1.add(b12);
pan1.add(b7);
pan1.add(b8);
pan1.add(b9);
pan1.add(b13);
pan1.add(b0);
pan1.add(b15);
pan1.add(b16);
pan1.add(b14);
pan1.add(bclar);
f.setSize(200,220);
f.setVisible(true);
}
catch(Exception e)
{
System.out.println(e.getMessage());
}

}
class A implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String a=text1.getText();
String s=e.getActionCommand();
if(a.equals("0.")||a.equals("+")||a.equals("-")||a.equals("*")||a.equals("/"))
text1.setText(s);
else {
if(flag2)
{
text1.setText(s);
flag2=false;
}
else
text1.setText(a+s);

}
}
}
class Opertion implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
cal=e.getActionCommand();
if(flag1==true)
source=text1.getText();
text1.setText(cal);
flag1=false;
flag=true;
}
}
class Result implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
double num1;
num1=Double.parseDouble(source);
object=text1.getText();
double num2;
num2=Double.parseDouble(object);
double result=0;
if(cal.equals("+"))
result=num1+num2;
if(cal.equals("-"))
result=num1-num2;
if(cal.equals("*"))
result=num1*num2;
if(cal.equals("/"))
if(num2==0)
text1.setText("除數不能為0");
else
result=num1/num2;
String s1=Double.toString(result);
text1.setText(s1);
flag1=true;
flag2=true;
}
}
class Clar implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
text1.setText("0.");
}
}

public static void main(String[] args)
{
Counter count=new Counter();
count.init();
}

public void windowClosing(WindowEvent e){
System.exit(1);
}
public void windowOpened(WindowEvent e){}
public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowClosed(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}
}

3. 用JAVA編寫一個類似於Windows操作系統的的科學計算器程序，要包括對數運算，階乘運算等等。

代碼如下：
import java.awt.*;
import java.awt.event.*;
import java.text.DecimalFormat;
import java.util.LinkedList;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
public class Calculation extends JPanel implements ActionListener{

int flag=1,n=0;//n標記上一步
String m="@";//暫存
LinkedList<String>num=new LinkedList<String>();
LinkedList<String>op=new LinkedList<String>();
String display="";
String str="";
JPanel p1=new JPanel();
JPanel p2=new JPanel();
JPanel p3=new JPanel();
JPanel p4=new JPanel();
JPanel p5=new JPanel();
JPanel p6=new JPanel();

Label l2=new Label("");

JTextField tf=new JTextField("",20);
JTextField tf1=new JTextField();

Button bt[]=new Button[27];
String[] ss={"BackSpace","CE","C","MC","MR","MS","M+","7","8","9","/","log",
"4","5","6","*","y^x","1","2","3","-","!","0","+/-",".","+","="};

public Calculation(){
setLayout(new BorderLayout(10,5));
//setResizable(false);

p1.setLayout(new BorderLayout(10,10));
p2.setLayout(new BorderLayout(10,10));//p5,p6
p3.setLayout(new GridLayout(1,3,5,5));//用於存放backspace,ce,c三鍵
p4.setLayout(new GridLayout(4,5,5,5));//用於存放數字區及附近共20鍵
p5.setLayout(new GridLayout(5,1,5,5));//用於存放MC,MR,MS,M+鍵及顯示M狀態文本框
p6.setLayout(new BorderLayout(10,5));//放p3 p4

tf.setBackground(new Color(255,255,255));
tf.setEditable(false);

tf1.setBackground(Color.gray);
tf1.setEditable(false);
tf1.setEnabled(false);

for(int i=0;i<27;i++){ //利用數組,構造帶指定標簽的按鈕
bt[i]=new Button(ss[i]);
bt[i].addActionListener(this);
}

add(p1,BorderLayout.CENTER);
p1.add(tf,BorderLayout.NORTH);
p1.add(p2,BorderLayout.CENTER);

p2.add(p5,BorderLayout.WEST);
p2.add(p6,BorderLayout.CENTER);

p6.add(p3,BorderLayout.NORTH);
p6.add(p4,BorderLayout.CENTER);

p3.add(bt[0]);
p3.add(bt[1]);
p3.add(bt[2]);

p5.add(tf1);
p5.add(bt[3]);
p5.add(bt[4]);
p5.add(bt[5]);
p5.add(bt[6]);

for(int i=7;i<27;i++){
p4.add(bt[i]);
}

setBounds(400,200,286,215);
setVisible(true);
//this.setDefaultCloseOperation(3);
}
}
完整已發到郵箱。

4. 用java編寫科學計算器的代碼！一定要有求立方

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
class Counter extends WindowAdapter
{
static JFrame f=new JFrame("計算器");
static JTextField text1=new JTextField("0.");
static String source="";
static String cal="";
static String object="";
static boolean flag=false;
static boolean flag1=true;
static boolean flag2=false;
public void init()
{
try
{
Container c=f.getContentPane();
JPanel pan1=new JPanel();
JButton b1=new JButton("1");
JButton b2=new JButton("2");
JButton b3=new JButton("3");
JButton b4=new JButton("4");
JButton b5=new JButton("5");
JButton b6=new JButton("6");
JButton b7=new JButton("7");
JButton b8=new JButton("8");
JButton b9=new JButton("9");
JButton b0=new JButton("0");
JButton b11=new JButton("+");
JButton b12=new JButton("-");
JButton b13=new JButton("*");
JButton b14=new JButton("/");
JButton b15=new JButton(".");
JButton b16=new JButton("=");
JButton bclar=new JButton("清零");
text1.setHorizontalAlignment(JTextField.RIGHT);
c.add(text1,"North");
c.add(pan1);
A aa=new A();
Result re=new Result();
Opertion op=new Opertion();
Clar cl=new Clar();
b1.addActionListener(aa);
b2.addActionListener(aa);
b3.addActionListener(aa);
b4.addActionListener(aa);
b5.addActionListener(aa);
b6.addActionListener(aa);
b7.addActionListener(aa);
b8.addActionListener(aa);
b9.addActionListener(aa);
b0.addActionListener(aa);
b11.addActionListener(op);
b12.addActionListener(op);
b13.addActionListener(op);
b14.addActionListener(op);
b16.addActionListener(re);
b15.addActionListener(aa);
bclar.addActionListener(cl);
pan1.add(b1);
pan1.add(b2);
pan1.add(b3);
pan1.add(b11);
pan1.add(b4);
pan1.add(b5);
pan1.add(b6);
pan1.add(b12);
pan1.add(b7);
pan1.add(b8);
pan1.add(b9);
pan1.add(b13);
pan1.add(b0);
pan1.add(b15);
pan1.add(b16);
pan1.add(b14);
pan1.add(bclar);
f.setSize(200,220);
f.setVisible(true);
}
catch(Exception e)
{
System.out.println(e.getMessage());
}

}
class A implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
String a=text1.getText();
String s=e.getActionCommand();
if(a.equals("0.")||a.equals("+")||a.equals("-")||a.equals("*")||a.equals("/"))
text1.setText(s);
else {
if(flag2)
{
text1.setText(s);
flag2=false;
}
else
text1.setText(a+s);

}
}
}
class Opertion implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
cal=e.getActionCommand();
if(flag1==true)
source=text1.getText();
text1.setText(cal);
flag1=false;
flag=true;
}
}
class Result implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
double num1;
num1=Double.parseDouble(source);
object=text1.getText();
double num2;
num2=Double.parseDouble(object);
double result=0;
if(cal.equals("+"))
result=num1+num2;
if(cal.equals("-"))
result=num1-num2;
if(cal.equals("*"))
result=num1*num2;
if(cal.equals("/"))
if(num2==0)
text1.setText("除數不能為0");
else
result=num1/num2;
String s1=Double.toString(result);
text1.setText(s1);
flag1=true;
flag2=true;
}
}
class Clar implements ActionListener
{
public void actionPerformed(ActionEvent e)
{
text1.setText("0.");
}
}

public static void main(String[] args)
{
Counter count=new Counter();
count.init();
}

public void windowClosing(WindowEvent e){
System.exit(1);
}
public void windowOpened(WindowEvent e){}
public void windowIconified(WindowEvent e){}
public void windowDeiconified(WindowEvent e){}
public void windowClosed(WindowEvent e){}
public void windowActivated(WindowEvent e){}
public void windowDeactivated(WindowEvent e){}
}

5. 求一Java科學計算器代碼

什麼地方不懂可以問我
import java.util.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.applet.*;
public class SZJSQ extends JApplet implements ActionListener
{
boolean i=true;
private JButton num0=new JButton("0");
private JButton num1=new JButton("1");
private JButton num2=new JButton("2");
private JButton num3=new JButton("3");
private JButton num4=new JButton("4");
private JButton num5=new JButton("5");
private JButton num6=new JButton("6");
private JButton num7=new JButton("7");
private JButton num8=new JButton("8");
private JButton num9=new JButton("9");
private JButton zuok=new JButton("(");
private JButton youk=new JButton(")");
private JButton dian=new JButton(".");
private JButton NULL=new JButton("N");
private JButton plu=new JButton("+");
private JButton min=new JButton("-");
private JButton mul=new JButton("x");
private JButton div=new JButton("/");
private JButton equ=new JButton("=");
private JButton cle=new JButton("C");//清除
private JTextField space=new JTextField(30);

public void init()
{
JPanel text=new JPanel();
text.setLayout(new FlowLayout());
text.add(space);
JPanel buttons=new JPanel();
buttons.setLayout(new GridLayout(5,4));
buttons.add(num9);
buttons.add(num8);
buttons.add(num7);
buttons.add(plu);
buttons.add(num6);
buttons.add(num5);
buttons.add(num4);
buttons.add(min);
buttons.add(num3);
buttons.add(num2);
buttons.add(num1);
buttons.add(mul);
buttons.add(num0);
buttons.add(cle);
buttons.add(equ);
buttons.add(div);
buttons.add(zuok);
buttons.add(youk);
buttons.add(dian);
buttons.add(NULL);
(num9).addActionListener(this);
(num8).addActionListener(this);
(num7).addActionListener(this);
(num6).addActionListener(this);
(num5).addActionListener(this);
(num4).addActionListener(this);
(num3).addActionListener(this);
(num2).addActionListener(this);
(num1).addActionListener(this);
(num0).addActionListener(this);
(plu).addActionListener(this);
(min).addActionListener(this);
(mul).addActionListener(this);
(div).addActionListener(this);
(equ).addActionListener(this);
(cle).addActionListener(this);
(zuok).addActionListener(this);
(youk).addActionListener(this);
(dian).addActionListener(this);
setLayout(new BorderLayout());
add("North",text);
add("South",buttons);
space.setText("0");
}

public void actionPerformed(ActionEvent e)
{

if(e.getSource()==num9)
{
if(i==true)
{
space.setText("9");
i=false;
}
else space.setText(space.getText()+'9');
}
if(e.getSource()==num8)
{
if(i==true)
{
space.setText("8");
i=false;
}
else space.setText(space.getText()+'8');
}
if(e.getSource()==num7)
{
if(i==true)
{
space.setText("7");
i=false;
}
else space.setText(space.getText()+'7');
}
if(e.getSource()==num6)
{
if(i==true)
{
space.setText("6");
i=false;
}
else space.setText(space.getText()+'6');
}
if(e.getSource()==num5)
{
if(i==true)
{
space.setText("5");
i=false;
}
else space.setText(space.getText()+'5');
}
if(e.getSource()==num4)
{
if(i==true)
{
space.setText("4");
i=false;
}
else space.setText(space.getText()+'4');
}
if(e.getSource()==num3)
{
if(i==true)
{
space.setText("3");
i=false;
}
else space.setText(space.getText()+'3');
}
if(e.getSource()==num2)
{
if(i==true)
{
space.setText("2");
i=false;
}
else space.setText(space.getText()+'2');
}
if(e.getSource()==num1)
{
if(i==true)
{
space.setText("1");
i=false;
}
else space.setText(space.getText()+'1');
}
if(e.getSource()==num0)
{
if(i==true)
{
space.setText("0");
i=false;
}
else space.setText(space.getText()+'0');
}
if(e.getSource()==zuok)
{
if(i==true)
{
space.setText("(");
i=false;
}
else space.setText(space.getText()+'(');
} if(e.getSource()==youk)
{
if(i==false)
space.setText(space.getText()+')');
}
if(e.getSource()==dian)
{
if(i==false)
space.setText(space.getText()+'.');
}
if(e.getSource()==plu)
{
space.setText(space.getText()+'+');
i=false;
}
if(e.getSource()==min)
{
space.setText(space.getText()+'-');
i=false;
}
if(e.getSource()==mul)
{
space.setText(space.getText()+'*');
i=false;
}
if(e.getSource()==div)
{
space.setText(space.getText()+'/');
i=false;
}
if(e.getSource()==equ)
{
space.setText(String.valueOf(Calculator(space.getText())));
i=true;
}
if(e.getSource()==cle)
{
space.setText("0");
i=true;
}

}

public double Calculator(String f)//科學計算
{
int i=0,j=0,k;
char c;
StringBuffer s=new StringBuffer();
s.append(f);
s.append('=');
String formula=s.toString();
char[] anArray;
anArray=new char[50];
Stack<Character> mystack=new Stack<Character>();
while(formula.charAt(i)!='=')
{
c=formula.charAt(i);
switch(c)
{
case '(': mystack.push(new Character(c));
i++;
break;
case ')':
while(mystack.peek().charValue()!='(')
{
anArray[j++]=mystack.pop().charValue();
}
mystack.pop();
i++;
break;
case '+':
case '-':
while(!mystack.empty()&&mystack.peek().charValue()!='(')
{
anArray[j++]=mystack.pop().charValue();

}
mystack.push(new Character(c));
i++;
break;
case '*':
case '/':
while(!mystack.empty()&&(mystack.peek().charValue()=='*'||mystack.peek().charValue()=='/'))
{
anArray[j++]=mystack.pop().charValue();
}
mystack.push(new Character(c));
i++;
break;
case' ': i++;
break;
default: while((c>='0'&&c<='9')||c=='.')
{
anArray[j++]=c;
i++;
c=formula.charAt(i);
}
anArray[j++]='#';
break;
}
}
while(!(mystack.empty()))
anArray[j++]=mystack.pop().charValue();

i=0;
int count;
double a,b,d;
Stack<Double> mystack1 =new Stack<Double>();
while(i<j)
{
c=anArray[i];
switch(c)
{
case '+':
a=mystack1.pop().doubleValue();
b=mystack1.pop().doubleValue();
d=b+a;
mystack1.push(new Double(d));
i++;
break;
case '-':
a=mystack1.pop().doubleValue();
b=mystack1.pop().doubleValue();
d=b-a;
mystack1.push(new Double(d));
i++;
break;
case '*':
a=mystack1.pop().doubleValue();
b=mystack1.pop().doubleValue();
d=b*a;
mystack1.push(new Double(d));
i++;
break;
case '/':
a=mystack1.pop().doubleValue();
b=mystack1.pop().doubleValue();
if(a!=0)
{
d=b/a;
mystack1.push(new Double(d));
i++;
}
else
{
System.out.println("Error!");
}
break;
default:
d=0;count=0;
while((c>='0'&&c<='9'))
{
d=10*d+c-'0';
i++;
c=anArray[i];
}
if(c=='.')
{
i++;
c=anArray[i];
while((c>='0'&&c<='9'))
{
count++;
d=d+(c-'0')/Math.pow(10,count);
i++;
c=anArray[i];
}
}
if(c=='#')
mystack1.push(new Double(d));
i++;
break;
}
}
return(mystack1.peek().doubleValue());
}
}

6. 用java.EE編寫計算器程序代碼

java EE是java企業級開發平台的意思，實在是看不出跟計算器這種小程序有什麼關聯。不知道樓主要找的是不是這個。
package ex1;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.text.DecimalFormat;

import javax.swing.BorderFactory;
import javax.swing.ButtonGroup;
import javax.swing.JButton;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JRadioButtonMenuItem;
import javax.swing.JTextField;

public class Calcutor extends JFrame {
private JTextField tf;
private JPanel panel1, panel2, panel3, panel4;
private JMenuBar myBar;
private JMenu menu1, menu2, menu3;
private JMenuItem editItem1, editItem2, help1, help2, help3;
private JRadioButtonMenuItem seeItem1, seeItem2;//單選框
private JCheckBoxMenuItem seeItem3;//復選框
private ButtonGroup bgb;
private String back;
private boolean IfResult = true, flag = false;
private String oper = "=";
private double result = 0;
private Num numActionListener;
private DecimalFormat df;

public Calcutor(){
super("科學計算器");//設置標題欄

df = new DecimalFormat("#.####");//保留四位小數

this.setLayout(new BorderLayout(10, 5));
panel1 = new JPanel(new GridLayout(1, 3, 10, 10));
panel2 = new JPanel(new GridLayout(5, 6, 5, 5));//5行6列
panel3 = new JPanel(new GridLayout(5, 1, 5, 5));
panel4 = new JPanel(new BorderLayout(5, 5));

/**
* 菜單欄
*/
myBar = new JMenuBar();
menu1 = new JMenu("編輯(E)");
menu2 = new JMenu("查看(V)");
menu3 = new JMenu("幫助(H)");

menu1.setFont(new Font("宋體", Font.PLAIN, 12));
menu2.setFont(new Font("宋體", Font.PLAIN, 12));
menu3.setFont(new Font("宋體", Font.PLAIN, 12));

/**
* 編輯欄
*/
editItem1 = new JMenuItem("復制(C) Ctrl+C");
editItem2 = new JMenuItem("粘貼(P) Ctrl+V");

editItem1.setFont(new Font("宋體",Font.PLAIN,12));
editItem2.setFont(new Font("宋體",Font.PLAIN,12));

/**
* 查看欄
*/
seeItem1 = new JRadioButtonMenuItem("科學型(T)");
seeItem2 = new JRadioButtonMenuItem("標准型(S)");
seeItem3 = new JCheckBoxMenuItem("數字分組(I)");

seeItem1.setFont(new Font("宋體",Font.PLAIN,12));
seeItem2.setFont(new Font("宋體",Font.PLAIN,12));
seeItem3.setFont(new Font("宋體",Font.PLAIN,12));

/**
* 幫助欄
*/
help1 = new JMenuItem("幫助主題(H)");
help2 = new JMenuItem("關於計算器(A)");

help1.setFont(new Font("宋體",Font.PLAIN,12));
help2.setFont(new Font("宋體",Font.PLAIN,12));

bgb = new ButtonGroup();//選項組

menu1.add(editItem1);
menu1.add(editItem2);

menu2.add(seeItem1);
menu2.add(seeItem2);
menu2.addSeparator();//添加一條分割線
menu2.add(seeItem3);

menu3.add(help1);
menu3.addSeparator();//添加一條分割線
menu3.add(help2);

myBar.add(menu1);
myBar.add(menu2);
myBar.add(menu3);

this.setJMenuBar(myBar);

numActionListener = new Num();//實現數字監聽

/**
* 文本域，即為計算器的屏幕顯示區域
*/
tf = new JTextField();
tf.setEditable(false);//文本區域不可編輯
tf.setBackground(Color.white);//文本區域的背景色
tf.setHorizontalAlignment(JTextField.RIGHT);//文字右對齊
tf.setText("0");
tf.setBorder(BorderFactory.createLoweredBevelBorder());
init();//對計算器進行初始化

}
/**
* 初始化操作
* 添加按鈕
*/
private void init(){
addButton(panel1, "Backspace", new Clear(), Color.red);
addButton(panel1, "CE", new Clear(), Color.red);
addButton(panel1, "C", new Clear(), Color.red);

addButton(panel2, "1/x", new Signs(), Color.magenta);
addButton(panel2, "log", new Signs(), Color.magenta);
addButton(panel2, "7", numActionListener, Color.blue);
addButton(panel2, "8", numActionListener, Color.blue);
addButton(panel2, "9", numActionListener, Color.blue);
addButton(panel2, "÷", new Signs(), Color.red);

addButton(panel2, "n!", new Signs(), Color.magenta);
addButton(panel2, "sqrt", new Signs(), Color.magenta);
addButton(panel2, "4", numActionListener, Color.blue);
addButton(panel2, "5", numActionListener, Color.blue);
addButton(panel2, "6", numActionListener, Color.blue);
addButton(panel2, "×", new Signs(), Color.red);

addButton(panel2, "sin", new Signs(), Color.magenta);
addButton(panel2, "x^2", new Signs(), Color.magenta);
addButton(panel2, "1", numActionListener, Color.blue);
addButton(panel2, "2", numActionListener, Color.blue);
addButton(panel2, "3", numActionListener, Color.blue);
addButton(panel2, "-", new Signs(), Color.red);

addButton(panel2, "cos", new Signs(), Color.magenta);
addButton(panel2, "x^3", new Signs(), Color.magenta);
addButton(panel2, "0", numActionListener, Color.blue);
addButton(panel2, "-/+", new Clear(), Color.blue);
addButton(panel2, ".", new Dot(), Color.blue);
addButton(panel2, "+", new Signs(), Color.red);

addButton(panel2, "tan", new Signs(), Color.magenta);
addButton(panel2, "%", new Signs(), Color.magenta);
addButton(panel2, "π", numActionListener, Color.orange);
addButton(panel2, "e", numActionListener, Color.orange);
addButton(panel2, "′″", new Signs(), Color.orange);
addButton(panel2, "=", new Signs(), Color.red);

JButton btns = new JButton("計算器");
btns.setBorder(BorderFactory.createLoweredBevelBorder());
btns.setEnabled(false);//按鈕不可操作
btns.setPreferredSize(new Dimension(20, 20));

panel3.add(btns);//加入按鈕
addButton(panel3, "MC", null, Color.red);
addButton(panel3, "MR", null, Color.red);
addButton(panel3, "MS", null, Color.red);
addButton(panel3, "M+", null, Color.red);

panel4.add(panel1, BorderLayout.NORTH);
panel4.add(panel2, BorderLayout.CENTER);
this.add(tf, BorderLayout.NORTH);
this.add(panel3, BorderLayout.WEST);
this.add(panel4);

pack();
this.setResizable(false);//窗口不可改變大小
this.setLocation(300, 200);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
/**
* 統一設置按鈕的的使用方式
* @param panel
* @param name
* @param action
* @param color
*/
private void addButton(JPanel panel, String name, ActionListener action, Color color){
JButton bt = new JButton(name);
panel.add(bt);//在面板上增加按鈕
bt.setForeground(color);//設置前景（字體）顏色
bt.addActionListener(action);//增加監聽事件
}
/**
* 計算器的基礎操作（+ - × ÷）
* @param x
*/
private void getResult (double x){
if(oper == "+"){result += x;}
else if(oper == "-"){result -= x;}
else if(oper == "×"){result *= x;}
else if(oper == "÷"){result /= x;}
else if(oper == "="){result = x;}
tf.setText(df.format(result));
}
/**
* 運算符號的事件監聽
*/
class Signs implements ActionListener{
public void actionPerformed(ActionEvent e) {
/*
* 用ActionEvent對象的getActionCommand()方法
* 取得與引發事件對象相關的字元串
*/
String str = e.getActionCommand();

/* sqrt求平方根 */
if(str.equals("sqrt")){
double i = Double.parseDouble(tf.getText());
if(i>=0){
/*
* String.valueOf() 轉換為字元串
* df.format() 按要求保留四位小數
* Math.sqrt() 求算數平方根
*/
tf.setText(String.valueOf(df.format(Math.sqrt(i))));
}
else{
tf.setText("負數不能開平方根");
}
}

/* log求常用對數 */
else if(str.equals("log")){
double i = Double.parseDouble(tf.getText());
if(i>0){
tf.setText(String.valueOf(df.format(Math.log(i))));
}else{
tf.setText("負數不能求對數");
}
}

/* %求百分比 */
else if(str.equals("%")){
tf.setText(df.format(Double.parseDouble(tf.getText()) / 100));
}

/* 1/x求倒數 */
else if(str.equals("1/x")){
if(Double.parseDouble(tf.getText()) == 0){
tf.setText("除數不能為零");
}else{
tf.setText(df.format(1 / Double.parseDouble(tf.getText())));
}
}

/* sin求正弦函數 */
else if(str.equals("sin")){
double i = Double.parseDouble(tf.getText());
tf.setText(String.valueOf(df.format(Math.sin(i))));
}

/* cos求餘弦函數 */
else if(str.equals("cos")){
double i = Double.parseDouble(tf.getText());
tf.setText(String.valueOf(df.format(Math.cos(i))));
}

/* tan求正切函數 */
else if(str.equals("tan")){
double i = Double.parseDouble(tf.getText());
tf.setText(String.valueOf(df.format(Math.tan(i))));
}

/* n!求階乘 */
else if(str.equals("n!")){
double i = Double.parseDouble(tf.getText());
if((i%2==0)||(i%2==1))//判斷為整數放進行階乘操作
{
int j = (int)i;//強制類型轉換
int result=1;
for(int k=1;k<=j;k++)
result *= k;
tf.setText(String.valueOf(result));
}
else
{
tf.setText("無法進行階乘");
}
}

/* x^2求平方 */
else if(str.equals("x^2")){
double i = Double.parseDouble(tf.getText());
tf.setText(String.valueOf(df.format(i*i)));
}

/* x^3求立方 */
else if(str.equals("x^3")){
double i = Double.parseDouble(tf.getText());
tf.setText(String.valueOf(df.format(i*i*i)));
}

/* ′″角度轉換 */
/**
* 將角度值轉換成弧度值，方便三角函數的計算
*/
else if(str.equals("′″")){
double i = Double.parseDouble(tf.getText());
tf.setText(String.valueOf(i/180*Math.PI));
}

else{
if(flag){
IfResult = false;
}
if(IfResult){
oper = str;
}else{
getResult(Double.parseDouble(tf.getText()));
oper = str;
IfResult = true;
}
}
}
}
/**
* 清除按鈕的事件監聽
*/
class Clear implements ActionListener{
public void actionPerformed(ActionEvent e) {
/*
* 用ActionEvent對象的getActionCommand()方法
* 取得與引發事件對象相關的字元串
*/
String str = e.getActionCommand();
if(str == "C"){
tf.setText("0");
IfResult = true;
result = 0;
}else if(str == "-/+"){
double i = 0 - Double.parseDouble(tf.getText().trim());
tf.setText(df.format(i));
}else if(str == "Backspace"){
if(Double.parseDouble(tf.getText()) > 0){
if(tf.getText().length() > 1){
tf.setText(tf.getText().substring(0, tf.getText().length() - 1));
//使用退格刪除最後一位字元
}else{
tf.setText("0");
IfResult = true;
}
}else{
if(tf.getText().length() > 2){
tf.setText(tf.getText().substring(0, tf.getText().length() - 1));
}else{
tf.setText("0");
IfResult = true;
}
}
}else if(str == "CE"){
tf.setText("0");
IfResult = true;
}
}
}
/**
* 數字輸入的事件監聽
*/
class Num implements ActionListener{
public void actionPerformed(ActionEvent e) {
String str = e.getActionCommand();
if(IfResult){
tf.setText("");
IfResult = false;
}
if(str=="π")
{
tf.setText(String.valueOf(Math.PI));
}
else if(str=="e")
{
tf.setText(String.valueOf(Math.E));
}
else{
tf.setText(tf.getText().trim() + str);
if(tf.getText().equals("0")){
tf.setText("0");
IfResult = true;
flag = true;
}
}
}
}
/**
* 小數點的事件監聽
*/
class Dot implements ActionListener{
public void actionPerformed(ActionEvent e) {
IfResult = false;
if(tf.getText().trim().indexOf(".") == -1){
tf.setText(tf.getText() + ".");
}
}
}
/**
* main方法
*/
public static void main(String[] args) {
new Calcutor().setVisible(true);
}
}

7. 用JAVA編寫一個計算器

importjava.awt.BorderLayout;

importjava.awt.Color;

importjava.awt.GridLayout;

importjava.awt.event.ActionEvent;

importjava.awt.event.ActionListener;

importjavax.swing.ImageIcon;

importjavax.swing.JButton;

importjavax.swing.JFrame;

importjavax.swing.JPanel;

importjavax.swing.JTextField;

importjavax.swing.SwingConstants;

{

/**

*

*/

=1L;

Resultresult=newResult();//定義text的面板

Number_Keynumber_key=newNumber_Key();//定義按鈕面板

//當點擊按鈕+、-、*、/時，com=true

booleancom=false;

//當i=0時說明是我們第一次輸入，字元串text不會累加

inti=0;

//存放text的內容

Stringtext="";

//存放點擊按鈕+、-、*、/之前的數值

doubledefbutton=0;

//+、-、*、/的代號分別為1，2，3，4

intsymbol=0;

//構造函數

Jisuanqi(){

super("WangJiao");//設定標題

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);//設定關閉窗體時退出程序

JPanelpane=newJPanel();//定義主面板

pane.setLayout(newBorderLayout());

setBounds(380,220,30,80);//前兩個參數是在屏幕上顯示的坐標，後兩個是大小

//替換圖標

ImageIconicon=newImageIcon("F:1.GIF");

//Jisuanqi.class.getResource("APPLE.GIF")

//);

setIconImage(icon.getImage());

pane.add(result,BorderLayout.NORTH);

pane.add(number_key,BorderLayout.CENTER);

pane.add(number_key.equal,BorderLayout.SOUTH);

number_key.one.addActionListener(this);//對1按鈕添加監聽事件

number_key.two.addActionListener(this);//對2按鈕添加監聽事件

number_key.three.addActionListener(this);//對3按鈕添加監聽事件

number_key.four.addActionListener(this);//對4按鈕添加監聽事件

number_key.five.addActionListener(this);//對5按鈕添加監聽事件

number_key.six.addActionListener(this);//對6按鈕添加監聽事件

number_key.seven.addActionListener(this);//對7按鈕添加監聽事件

number_key.eight.addActionListener(this);//對8按鈕添加監聽事件

number_key.nine.addActionListener(this);//對9按鈕添加監聽事件

number_key.zero.addActionListener(this);//對0按鈕添加監聽事件

number_key.ce.addActionListener(this);//對置零按鈕添加監聽事件

number_key.plus.addActionListener(this);//對+按鈕添加監聽事件

number_key.equal.addActionListener(this);//對=按鈕添加監聽事件

number_key.sub.addActionListener(this);//對-按鈕添加監聽事件

number_key.mul.addActionListener(this);//對*按鈕添加監聽事件

number_key.div.addActionListener(this);//對/按鈕添加監聽事件

number_key.point.addActionListener(this);//對.按鈕添加監聽事件

setContentPane(pane);

pack();//初始化窗體大小為正好盛放所有按鈕

}

//各個按鈕觸發的事件

publicvoidactionPerformed(ActionEvente){

/*

*如果是點擊數字按鈕那麼先要判斷是否在此之前點擊了+、-、*、/、=，如果是那麼com=true如果沒有com=

*false;或者是否點擊數字鍵，如果是i=1,如果沒有i=0;

*/

if(e.getSource()==number_key.one){

if(com||i==0){

result.text.setText("1");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"1");

}

}elseif(e.getSource()==number_key.two){

if(com||i==0){

result.text.setText("2");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"2");

}

}elseif(e.getSource()==number_key.three){

if(com||i==0){

result.text.setText("3");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"3");

}

}elseif(e.getSource()==number_key.four){

if(com||i==0){

result.text.setText("4");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"4");

}

}elseif(e.getSource()==number_key.five){

if(com||i==0){

result.text.setText("5");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"5");

}

}elseif(e.getSource()==number_key.six){

if(com||i==0){

result.text.setText("6");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"6");

}

}elseif(e.getSource()==number_key.seven){

if(com||i==0){

result.text.setText("7");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"7");

}

}elseif(e.getSource()==number_key.eight){

if(com||i==0){

result.text.setText("8");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"8");

}

}elseif(e.getSource()==number_key.nine){

if(com||i==0){

result.text.setText("9");

com=false;

i=1;

}else{

text=result.text.getText();

result.text.setText(text+"9");

}

}

/*

*對於0這個按鈕有一定的說法，在我的程序里不會出現如00000這樣的情況，我加了判斷條件就是

*如果text中的數值=0就要判斷在這個數值中是否有.存在?如果有那麼就在原來數值基礎之上添加0;否則保持原來的數值不變

*/

elseif(e.getSource()==number_key.zero){//result.text.getText()是得到text里內容的意思

if(com||i==0){

result.text.setText("0");

com=false;

i=1;

}else{

text=result.text.getText();

if(Float.parseFloat(text)>0||Float.parseFloat(text)<0){//Float.parseFloat(text)就是類型轉換了，下面都是一樣

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

}else{

if(text.trim().indexOf(".")==-1){

result.text.setText(text);

}else{

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

}

}

}

}elseif(e.getSource()==number_key.ce){

result.text.setText("0");

i=0;

com=true;

//text="";

defbutton=0;

}

/*

*本程序不會讓一個數值中出現2個以上的小數點.具體做法是:判斷是否已經存在.存在就不添加,不存在就添加.

*/

elseif(e.getSource()==number_key.point){

if(com||i==0){

result.text.setText("0.");

com=false;

i=1;

}else{

text=result.text.getText();

if(text.trim().indexOf(".")==-1){

result.text.setText(text+".");

}else{

result.text.setText(text);

}

}

}//獲得點擊+之前的數值

elseif(e.getSource()==number_key.plus){

com=true;

i=0;

defbutton=Double.parseDouble(result.text.getText());

symbol=1;

}//獲得點擊-之前的數值

elseif(e.getSource()==number_key.sub){

com=true;

i=0;

defbutton=Double.parseDouble(result.text.getText());

symbol=2;

}//獲得點擊*之前的數值

elseif(e.getSource()==number_key.mul){

com=true;

i=0;

defbutton=Double.parseDouble(result.text.getText());

System.out.println(defbutton);

symbol=3;

}//獲得點擊/之前的數值

elseif(e.getSource()==number_key.div){

com=true;

i=0;

defbutton=Double.parseDouble(result.text.getText());

symbol=4;

}elseif(e.getSource()==number_key.equal){

switch(symbol){

case1:{//計算加法

doublead=defbutton

+Double.parseDouble(result.text.getText());

result.text.setText(ad+"");

i=0;

text="";

break;

}

case2:{//計算減法

doublead=defbutton

-Double.parseDouble(result.text.getText());

result.text.setText(String.valueOf(ad));

i=0;

text="";

break;

}

case3:{//計算乘法

doublead=defbutton

*Double.parseDouble(result.text.getText());

result.text.setText(ad+"");

i=0;

text="";

break;

}

case4:{//計算除法

doublead=defbutton

/Double.parseDouble(result.text.getText());

result.text.setText(ad+"");

i=0;

text="";

break;

}

}

System.out.println(com);

}

System.out.println(result.text.getText());

}

@SuppressWarnings("deprecation")

publicstaticvoidmain(String[]args){

Jisuanqiloveyou=newJisuanqi();

loveyou.show();

}

}

//計算器數字按鈕定義面板

classNumber_KeyextendsJPanel{

/**

*

*/

=1L;

JButtonzero=newJButton("0");//數字鍵0

JButtonone=newJButton("1");//數字鍵1

JButtontwo=newJButton("2");//數字鍵2

JButtonthree=newJButton("3");//數字鍵3

JButtonfour=newJButton("4");//數字鍵4

JButtonfive=newJButton("5");//數字鍵5

JButtonsix=newJButton("6");//數字鍵6

JButtonseven=newJButton("7");//數字鍵7

JButtoneight=newJButton("8");//數字鍵8

JButtonnine=newJButton("9");//數字鍵9

JButtonplus=newJButton("+");

JButtonsub=newJButton("-");

JButtonmul=newJButton("*");

JButtondiv=newJButton("/");

JButtonequal=newJButton("=");

JButtonce=newJButton("清零");//置零鍵

JButtonpoint=newJButton(".");

Number_Key(){

setLayout(newGridLayout(4,4,1,1));//定義布局管理器為網格布局

setBackground(Color.blue);//設置背景顏色

//添加按鈕

add(one);

add(two);

add(three);

add(four);

add(five);

add(six);

add(seven);

add(eight);

add(nine);

add(zero);

add(plus);

add(sub);

add(mul);

add(div);

add(point);

add(equal);

add(ce);

}

}

//計算器顯示結果的窗體

classResultextendsJPanel{

/**

*

*/

=1L;

//text先是輸入和結果

JTextFieldtext=newJTextField("0");

@SuppressWarnings("deprecation")

Result(){//講輸入的數字或得到的結果在text的右邊顯示

text.setHorizontalAlignment(SwingConstants.RIGHT);

text.enable(false);//文本框不能編輯

setLayout(newBorderLayout());//設定布局管理器邊框布局

add(text,BorderLayout.CENTER);//text放置在窗體的中間

}

}

直接復制保存成Jisuanqi.java可以直接運行了

8. 計算器java代碼

import java.awt.Color;
import java.awt.Font;
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.JLabel;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.WindowConstants;
import javax.swing.border.LineBorder;

class Normal{
double i,j;
public Normal(double num1,double num2){
i=num1;
j=num2;
}
public double puls(){
return i+j;
}
public double subtract(){
return i-j;
}
public double multiply(){
return i*j;
}
public double divide(){
return i/j;
}
public double surpuls(){
return i%j;
}
}
class scientific extends Normal{
public scientific(int num1, int num2) {
super(num1, num2);
}
}
public class calc extends JFrame{
public static void main(String[] args) {
viewNormal VN= new viewNormal("normal");

}
}
class viewNormal extends JFrame implements ActionListener{
JPanel jp1 = new JPanel(new GridLayout(4,3,5,5));
JPanel jp2 = new JPanel(new GridLayout(5,1,5,5));
JLabel jl;
JButton[] jb;
JButton jbs,jbo,jba,jbb,jbc,jby;
StringBuffer sb = new StringBuffer();
Normal normal;
int dot=0;
double fnum=0;
double lnum=0;
double result;
String sign=null;
public viewNormal(String title){
setTitle(title);
setLayout(null);
setVisible(true);
setBounds(200,200,305,350);
setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
jb= new JButton[12];
for(int i=0;i<9;i++){
jb[i]=new JButton(""+(i+1));
jp1.add(jb[i]);
jb[i].addActionListener(this);
}
jb[9]=new JButton(".");
jb[10]=new JButton("0");
jb[11]=new JButton("=");
jb[9].addActionListener(this);
jb[10].addActionListener(this);
jb[11].addActionListener(this);
jp1.add(jb[9]);
jp1.add(jb[10]);
jp1.add(jb[11]);
jp1.setBounds(10, 100, 200, 200);
jbs= new JButton("+");jbo= new JButton("-");jba= new JButton("*");
jbb= new JButton("/");jby= new JButton("%");jbc= new JButton("C");
jbs.addActionListener(this);jbo.addActionListener(this);jba.addActionListener(this);
jbb.addActionListener(this);jby.addActionListener(this);jbc.addActionListener(this);
//jp2.add(jby);
jp2.add(jbs);jp2.add(jbo);jp2.add(jba);jp2.add(jbb);jp2.add(jbc);
jp2.setBounds(215, 100, 70, 200);
jl= new JLabel("0",JLabel.RIGHT);
jl.setFont(new Font("Batang",Font.BOLD, 20));
jl.setBorder(new LineBorder(Color.black,2));
jl.setBackground(Color.white);
jl.setBounds(10, 40, 275, 50);
jl.setOpaque(true);
add(jl);
add(jp1);
add(jp2);
}
//+
public void sum(){
lnum=Double.parseDouble(sb.toString());
normal=new Normal(fnum,lnum);
fnum=normal.puls();
result=fnum;
}
//-
private void sub() {
System.out.println(sb.toString());
lnum=Double.parseDouble(sb.toString());
normal=new Normal(fnum,lnum);
fnum=normal.subtract();
result=fnum;
}
//*
private void mul() {
lnum=Double.parseDouble(sb.toString());
normal=new Normal(fnum,lnum);
fnum=normal.multiply();
result=fnum;
}
// /
private void div() {
lnum=Double.parseDouble(sb.toString());
normal=new Normal(fnum,lnum);
fnum=normal.divide();
result=fnum;
}
//%
private void sur() {
lnum=Double.parseDouble(sb.toString());
normal=new Normal(fnum,lnum);
fnum=normal.surpuls();
result=fnum;
}
// =
private void same(){
if(sign.equals("+")){
sum();
}
if(sign.equals("-")){
sub();
}
if(sign.equals("*")){
mul();
}
if(sign.equals("/")){
div();
}
if(sign.equals("%")){
sur();
}
}
//result
public void Result(){
if(result%1!=0)
jl.setText(""+result);
else
{
int i=(int)result;
jl.setText(""+i);
}
}
@Override
public void actionPerformed(ActionEvent e) {
//System.out.println(sb.toString());
// 1~9
for(int i=0;i<9;i++){
if(e.getSource()==jb[i]&&!sb.toString().equals("0")){
sb.append(jb[i].getText());
jl.setText(sb.toString());
}
else if(e.getSource()==jb[i]&&sb.toString().equals("0")){
int d=sb.length();
sb.delete(0, d);
sb.append(jb[i].getText());
jl.setText(sb.toString());
}
}
// 0
if(e.getSource()==jb[10]&&!sb.toString().equals("0")){
sb.append(jb[10].getText());
jl.setText(sb.toString());
}
// .
if(e.getSource()==jb[9]&&dot==0&&!sb.toString().equals("")){
dot++;
sb.append(jb[9].getText());
jl.setText(sb.toString());
}
// =
if(e.getSource()==jb[11]&&!sb.toString().equals("")){
same();
Result();
int d=sb.length();
sb.delete(0, d);
dot=0;
}
// +
if(e.getSource()==jbs&&!sb.toString().equals("")){
if(sign!="+"&&sign!=null)
same();
else
sum();
sign ="+";
Result();
int d=sb.length();
sb.delete(0, d);
dot=0;
}
//-
if(e.getSource()==jbo&&!sb.toString().equals("")){
if(fnum==0)
fnum=2*Double.parseDouble(sb.toString());
if(sign!="-"&&sign!=null)
same();
else
sub();
sign ="-";
Result();
int d=sb.length();
sb.delete(0, d);
dot=0;
}
//*
if(e.getSource()==jba&&!sb.toString().equals("")){
if(fnum==0)
fnum=1;
if(sign!="*"&&sign!=null)
same();
else
mul();
sign ="*";
Result();
int d=sb.length();
sb.delete(0, d);
dot=0;
}
// /
if(e.getSource()==jbb&&!sb.toString().equals("")){
if(fnum==0)
fnum=Math.pow(Double.parseDouble(sb.toString()),2);
if(sign!="/"&&sign!=null)
same();
else
div();
sign ="/";
Result();
int d=sb.length();
sb.delete(0, d);
dot=0;
}
//%
// if(e.getSource()==jby&&!sb.toString().equals("")){
// if(fnum==0){
// fnum=Double.parseDouble(sb.toString());
// result=fnum;
// }
// else {
// if(sign!="%"&&sign!=null)
// same();
// else{
// lnum=Double.parseDouble(sb.toString());
// normal=new Normal(fnum,lnum);
// fnum=normal.surpuls();
// result=fnum;
// }
// }
// sign ="%";
// Result();
// int d=sb.length();
// sb.delete(0, d);
// dot=0;
// }
//clear
if(e.getSource()==jbc){
int d=sb.length();
sb.delete(0, d);
jl.setText("0");
dot=0;
fnum=0;
lnum=0;
sign=null;
}
}
}
class viewScientific extends viewNormal{
public viewScientific(String title){
super(title);
setBounds(200,200,800,500);
}
}

//等號以後輸入符號用不了， String轉 double 本來就有錯誤，你可以用我的擴展成科學型的。