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Calculator.exe

Calculator.java

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Calculator implements ActionListener
{
 JButton bt_1, bt_2, bt_3, bt_4, bt_5, bt_6, bt_7, bt_8, bt_9, bt_0,
   bt_Plus, bt_Minus, bt_Multiplication, bt_Division, bt_Dot, bt_Cal,
   bt_BackSpace, bt_C;
 JTextField tf_Display;
 StringBuffer tf_getText;
 String getText;
 
 double cal_Buffer1, cal_Buffer2, cal_Buffer3;
 final byte PLUS = 1, MINUS = 2, MULTIPLICATION = 3, DIVISION = 4;
 byte cal_Check, numberIn;

 public Calculator()
 {
  tf_getText = new StringBuffer();
  frameSetting();
 }

 public void frameSetting()
 {
  tf_Display = new JTextField("0");
  tf_Display.setHorizontalAlignment(JTextField.RIGHT);
  tf_Display.setFont(new Font("font", Font.BOLD, 16));
  tf_Display.setEditable(false);
  
  bt_1 = new JButton("1");
  bt_1.setFont(new Font("font", Font.BOLD, 16));
  bt_2 = new JButton("2");
  bt_2.setFont(new Font("font", Font.BOLD, 16));
  bt_3 = new JButton("3");
  bt_3.setFont(new Font("font", Font.BOLD, 16));
  bt_4 = new JButton("4");
  bt_4.setFont(new Font("font", Font.BOLD, 16));
  bt_5 = new JButton("5");
  bt_5.setFont(new Font("font", Font.BOLD, 16));
  bt_6 = new JButton("6");
  bt_6.setFont(new Font("font", Font.BOLD, 16));
  bt_7 = new JButton("7");
  bt_7.setFont(new Font("font", Font.BOLD, 16));
  bt_8 = new JButton("8");
  bt_8.setFont(new Font("font", Font.BOLD, 16));
  bt_9 = new JButton("9");
  bt_9.setFont(new Font("font", Font.BOLD, 16));
  bt_0 = new JButton("0");
  bt_0.setFont(new Font("font", Font.BOLD, 16));
  bt_Plus = new JButton("＋");
  bt_Plus.setFont(new Font("font", Font.BOLD, 16));
  bt_Minus = new JButton("－");
  bt_Minus.setFont(new Font("font", Font.BOLD, 16));
  bt_Multiplication = new JButton("×");
  bt_Multiplication.setFont(new Font("font", Font.BOLD, 16));
  bt_Division = new JButton("÷");
  bt_Division.setFont(new Font("font", Font.BOLD, 16));
  bt_Dot = new JButton(".");
  bt_Dot.setFont(new Font("font", Font.BOLD, 16));
  bt_Cal = new JButton("=");
  bt_Cal.setFont(new Font("font", Font.BOLD, 16));
  bt_BackSpace = new JButton("←");
  bt_BackSpace.setFont(new Font("font", Font.BOLD, 14));
  bt_C = new JButton(" C ");
  bt_C.setFont(new Font("font", Font.BOLD, 14));
  JPanel panel_North = new JPanel(new GridLayout(1,1,5,5));
  JPanel panel_Center = new JPanel(new BorderLayout());
  JPanel panel_C_North = new JPanel();
  JPanel panel_C_Center = new JPanel(new GridLayout(4,4,5,5));
  JLabel lb_Info = new JLabel("Copyright(c) 2007. Dscythe(Paik Seung Ik)", SwingConstants.CENTER);

  try {
   UIManager.setLookAndFeel(
    UIManager.getCrossPlatformLookAndFeelClassName());
  } catch (Exception e) { }

  JFrame.setDefaultLookAndFeelDecorated(true);
  JFrame frame = new JFrame(" Swing Calendar");

  frame.add(panel_North, "North");
  panel_North.add(tf_Display);

  frame.add(panel_Center, "Center");
  panel_Center.add(panel_C_North, "North");
  panel_C_North.add(bt_BackSpace);
  panel_C_North.add(bt_C);
  panel_Center.add(panel_C_Center, "Center");
  panel_C_Center.add(bt_7);
  panel_C_Center.add(bt_8);
  panel_C_Center.add(bt_9);
  panel_C_Center.add(bt_Division);
  panel_C_Center.add(bt_4);
  panel_C_Center.add(bt_5);
  panel_C_Center.add(bt_6);
  panel_C_Center.add(bt_Multiplication);
  panel_C_Center.add(bt_1);
  panel_C_Center.add(bt_2);
  panel_C_Center.add(bt_3);
  panel_C_Center.add(bt_Minus);
  panel_C_Center.add(bt_0);
  panel_C_Center.add(bt_Dot);
  panel_C_Center.add(bt_Cal);
  panel_C_Center.add(bt_Plus);
  panel_Center.add(lb_Info, "South");

  eventListener();

  frame.setSize(250,250);
  frame.setLocation(300,300);
  frame.setVisible(true);
  frame.setResizable(false);
  frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
 }

 public void eventListener()
 {
  bt_1.addActionListener(this);
  bt_2.addActionListener(this);
  bt_3.addActionListener(this);
  bt_4.addActionListener(this);
  bt_5.addActionListener(this);
  bt_6.addActionListener(this);
  bt_7.addActionListener(this);
  bt_8.addActionListener(this);
  bt_9.addActionListener(this);
  bt_0.addActionListener(this);
  bt_Plus.addActionListener(this);
  bt_Minus.addActionListener(this);
  bt_Multiplication.addActionListener(this);
  bt_Division.addActionListener(this);
  bt_Dot.addActionListener(this);
  bt_Cal.addActionListener(this);
  bt_BackSpace.addActionListener(this);
  bt_C.addActionListener(this);
  tf_Display.addKeyListener(new keyAdapter()
   {
    public void keyTyped (KeyEvent ke)
    {
     char key_Cr = ke.getKeyChar();
     //System.out.println(key_Cr);
     if ('1' == key_Cr){
      numberIn = 1;
      numberInput();
     } else if ('2' == key_Cr){
      numberIn = 2;
      numberInput();
     } else if ('3' == key_Cr){
      numberIn = 3;
      numberInput();
     } else if ('4' == key_Cr){
      numberIn = 4;
      numberInput();
     } else if ('5' == key_Cr){
      numberIn = 5;
      numberInput();
     } else if ('6' == key_Cr){
      numberIn = 6;
      numberInput();
     } else if ('7' == key_Cr){
      numberIn = 7;
      numberInput();
     } else if ('8' == key_Cr){
      numberIn = 8;
      numberInput();
     } else if ('9' == key_Cr){
      numberIn = 9;
      numberInput();
     } else if ('0' == key_Cr){
      zero();
     } else if ('+' == key_Cr){
      calculate(PLUS);
     } else if ('-' == key_Cr){
      calculate(MINUS);
     } else if ('*' == key_Cr){
      calculate(MULTIPLICATION);
     } else if ('/' == key_Cr){
      calculate(DIVISION);
     } else if ('.' == key_Cr){
      dotCheck();
     } else if ('' == key_Cr){
      backSpace();
     }
    }
   });
 }

 public void actionPerformed(ActionEvent e)
 {
  Object obj = e.getSource();
  if (bt_1 == obj){
   numberIn = 1;
   numberInput();
  } else if (bt_2 == obj){
   numberIn = 2;
   numberInput();
  } else if (bt_3 == obj){
   numberIn = 3;
   numberInput();
  } else if (bt_4 == obj){
   numberIn = 4;
   numberInput();
  } else if (bt_5 == obj){
   numberIn = 5;
   numberInput();
  } else if (bt_6 == obj){
   numberIn = 6;
   numberInput();
  } else if (bt_7 == obj){
   numberIn = 7;
   numberInput();
  } else if (bt_8 == obj){
   numberIn = 8;
   numberInput();
  } else if (bt_9 == obj){
   numberIn = 9;
   numberInput();
  } else if (bt_0 == obj){
   zero();
  } else if (bt_Plus == obj){
   calculate(PLUS);
  } else if (bt_Minus == obj){
   calculate(MINUS);
  } else if (bt_Multiplication == obj){
   calculate(MULTIPLICATION);
  } else if (bt_Division == obj){
   calculate(DIVISION);
  } else if (bt_Dot == obj){
   dotCheck();
  } else if (bt_C == obj){
   tf_Display.setText("0");
   tf_getText.delete(0,tf_getText.length());
   cal_Buffer1 = 0;
   cal_Buffer2 = 0;
   cal_Check = 0;
   numberIn = 0;
  } else if (bt_BackSpace == obj){
   backSpace();
  } else if (bt_Cal == obj)
  {
   result();
  }
 }

 public void numberInput()
 {
  getText = tf_getText.toString();
  if (getText.length() == 1 && getText.indexOf("0") == 0)
  {
   tf_getText.delete(0,tf_getText.length());
  }
  tf_getText.append("" + numberIn);
  tf_Display.setText(tf_getText.toString());
 }

 public void zero()
 {
  getText = tf_getText.toString();
  if (0 <= getText.indexOf("."))
  {
   tf_getText.append("0");
   tf_Display.setText(tf_getText.toString());
  } else {
   if (getText.length() == 1 && getText.indexOf("0") == 0)
   {
    tf_Display.setText("0");
   }else
   {
    tf_getText.append("0");
    tf_Display.setText(tf_getText.toString());
   }
  }
 }

 public void dotCheck()
 {
  getText = tf_getText.toString();
  if (0 <= getText.indexOf("."))
  {
   tf_getText.append("");
   tf_Display.setText(tf_getText.toString());
  } else {
   tf_getText.append(".");
   tf_Display.setText(tf_getText.toString());
  }
 }

 public void backSpace()
 {
  try
  {
   tf_getText.delete(0,tf_getText.length());
   tf_getText.append(tf_Display.getText());
   getText = tf_getText.delete(tf_getText.length()-1, tf_getText.length()).toString();
   if (getText.length() == 0)
   {
    getText = "0";
   }
   tf_getText.delete(0,tf_getText.length());
   tf_getText.append(getText);
   tf_Display.setText(tf_getText.toString());
  }
  catch (StringIndexOutOfBoundsException se){}
 }

 public void calculate(byte cal_Check)
 {
  try
  {
   switch (cal_Check)
   {
    case PLUS:
     cal_Buffer1 = Double.parseDouble(tf_Display.getText());
     cal_Buffer2 = cal_Buffer1 + cal_Buffer2;
     tf_getText.delete(0,tf_getText.length());
     tf_Display.setText("" + cal_Buffer2);
     break;
    case MINUS:
     cal_Buffer1 = Double.parseDouble(tf_Display.getText());
     if (cal_Buffer2 == 0)
     {
      cal_Buffer2 = cal_Buffer1;
     } else
     {
      cal_Buffer2 = cal_Buffer2 - cal_Buffer1;
     }
     tf_getText.delete(0,tf_getText.length());
     tf_Display.setText("" + cal_Buffer2);
     break;
    case MULTIPLICATION:
     cal_Buffer1 = Double.parseDouble(tf_Display.getText());
     if (cal_Buffer2 == 0)
     {
      cal_Buffer2 = cal_Buffer1;
     } else
     {
      cal_Buffer2 = cal_Buffer2 * cal_Buffer1;
     }
     tf_getText.delete(0,tf_getText.length());
     tf_Display.setText("" + cal_Buffer2);
     break;
    case DIVISION:
     cal_Buffer1 = Double.parseDouble(tf_Display.getText());
     if (cal_Buffer2 == 0)
     {
      cal_Buffer2 = cal_Buffer1;
     } else
     {
      cal_Buffer2 = cal_Buffer2 / cal_Buffer1;
     }
     tf_getText.delete(0,tf_getText.length());
     tf_Display.setText("" + cal_Buffer2);
     break;
 
    default :
   }
  } catch(NumberFormatException ne) {}
  this.cal_Check = cal_Check;
 }

 public void result()
 {
  try
  {
   if (cal_Check == PLUS)
   {
    String result = cal_Buffer2 + Double.parseDouble(tf_Display.getText()) + "";
    tf_Display.setText(result);
   } else if (cal_Check == MINUS)
   {
    String result = cal_Buffer2 - Double.parseDouble(tf_Display.getText()) + "";
    tf_Display.setText(result);
   } else if (cal_Check == MULTIPLICATION)
   {
    String result = cal_Buffer2 * Double.parseDouble(tf_Display.getText()) + "";
    tf_Display.setText(result);
   } else if (cal_Check == DIVISION)
   {
    String result = cal_Buffer2 / Double.parseDouble(tf_Display.getText()) + "";
    tf_Display.setText(result);
   }
  }
  catch (NumberFormatException ne){}
  tf_getText.delete(0,tf_getText.length());
  cal_Buffer1 = 0;
  cal_Buffer2 = 0;
 }

 public static void main(String[] args)
 {
  new Calculator();
 }
}

class keyAdapter implements KeyListener
{
 public void keyPressed (KeyEvent e){}
 public void keyReleased (KeyEvent e){}
 public void keyTyped (KeyEvent e){}
}