PocketCalc
/////////////////////////////////////////////////////////////////////
//
// PocketCalc emulates a pocket calculator of the simplest
// kind. It was Mikael Bonnier's first Java program.
//
// PocketCalc v1.0b1 is Freeware
// Commercial Distribution Restricted
// Copyright (C) 1995 by Mikael Bonnier, Lund, Sweden.
//
//
// It was developed using JDK-beta2 on Windows 95.
//
// Suggestions, improvements, and bug-reports
// are always welcome to:
// Mikael Bonnier
// Osten Undens gata 88
// S-227 62 LUND
// SWEDEN
//
// Or use my internet addresses:
// mikaelb@df.lth.se
// http://www.df.lth.se/~mikaelb
//
// Mikael Bonnier
/////////////////////////////////////////////////////////////////////
import java.awt.*;
import java.applet.Applet;
public class PocketCalc extends Applet
{
TextField txtDisp;
public final int OP_NONE = 0;
public final int OP_ADD = 1;
public final int OP_SUB = 2;
public final int OP_MUL = 3;
public final int OP_DIV = 4;
public final int OP_NEG = 5;
public final int OP_SQRT = 6;
public final int OP_EQ = 7;
public final int OP_C = 8;
public final int OP_AC = 9;
public final int DECSEP = -1;
String msDecimal;
int mnOp = OP_NONE;
boolean mbNewNumber = true;
boolean mbDecimal = false;
double mdReg = 0.0;
public void init()
{
CalcButton btn0, btn1, btn2, btn3, btn4, btn5, btn6, btn7, btn8, btn9;
CalcButton btnDecSep, btnNeg, btnSqrt, btnPlus, btnMinus;
CalcButton btnTimes, btnDiv, btnEqual, btnClear, btnAllClear;
setLayout(null);
setFont(new Font("Helvetica", Font.PLAIN, 14));
setBackground(new Color(0xFF, 0x80, 0x00));
btn0 = new CalcButton("0", OP_NONE, 0);
add(btn0);
btn0.reshape(64, 144, 96, 24);
btn1 = new CalcButton("1", OP_NONE, 1);
add(btn1);
btn1.reshape(64, 112, 40, 24);
btn2 = new CalcButton("2", OP_NONE, 2);
add(btn2);
btn2.reshape(120, 112, 40, 24);
btn3 = new CalcButton("3", OP_NONE, 3);
add(btn3);
btn3.reshape(176, 112, 40, 24);
btn4 = new CalcButton("4", OP_NONE, 4);
add(btn4);
btn4.reshape(64, 80, 40, 24);
btn5 = new CalcButton("5", OP_NONE, 5);
add(btn5);
btn5.reshape(120, 80, 40, 24);
btn6 = new CalcButton("6", OP_NONE, 6);
add(btn6);
btn6.reshape(176, 80, 40, 24);
btn7 = new CalcButton("7", OP_NONE, 7);
add(btn7);
btn7.reshape(64, 48, 40, 24);
btn8 = new CalcButton("8", OP_NONE, 8);
add(btn8);
btn8.reshape(120, 48, 40, 24);
btn9 = new CalcButton("9", OP_NONE, 9);
add(btn9);
btn9.reshape(176, 48, 40, 24);
btnDecSep = new CalcButton("·", OP_NONE, DECSEP);
add(btnDecSep);
btnDecSep.reshape(176, 144, 40, 24);
btnNeg = new CalcButton("+/-", OP_NEG, 0);
add(btnNeg);
btnNeg.reshape(8, 48, 40, 24);
btnSqrt = new CalcButton("Sqrt", OP_SQRT, 0);
add(btnSqrt);
btnSqrt.reshape(8, 80, 40, 24);
btnPlus = new CalcButton("+", OP_ADD, 0);
add(btnPlus);
btnPlus.reshape(232, 112, 40, 56);
btnMinus = new CalcButton("-", OP_SUB, 0);
add(btnMinus);
btnMinus.reshape(288, 112, 40, 24);
btnTimes = new CalcButton("×", OP_MUL, 0);
add(btnTimes);
btnTimes.reshape(232, 80, 40, 24);
btnDiv = new CalcButton("÷", OP_DIV, 0);
add(btnDiv);
btnDiv.reshape(288, 80, 40, 24);
btnEqual = new CalcButton("=", OP_EQ, 0);
add(btnEqual);
btnEqual.reshape(288, 144, 40, 24);
btnClear = new CalcButton("C", OP_C, 0);
add(btnClear);
btnClear.reshape(8, 112, 40, 24);
btnAllClear = new CalcButton("AC", OP_AC, 0);
add(btnAllClear);
btnAllClear.reshape(8, 144, 40, 24);
txtDisp = new TextField("0", 80);
txtDisp.setEditable(false);
add(txtDisp);
txtDisp.reshape(64, 8, 268, 27);
String sOneTenth = (new Double(0.1)).toString();
msDecimal = sOneTenth.substring(sOneTenth.length()-2).substring(0, 1);
}
public static void main(String args[])
{
Frame frm = new Frame("Pocket Calculator");
PocketCalc ex1 = new PocketCalc();
ex1.init();
frm.add("Center", ex1);
frm.pack();
frm.resize(395, 179);
frm.show();
}
public void append(int nValue)
{
String sDigit;
if(nValue == DECSEP)
if(!mbDecimal)
{
if(mbNewNumber)
{
txtDisp.setText("0");
mbNewNumber = false;
}
mbDecimal = true;
sDigit = msDecimal;
}
else
return;
else
sDigit = (new Integer(nValue)).toString();
if(mbNewNumber)
{
txtDisp.setText(sDigit);
mbNewNumber = false;
}
else
txtDisp.setText(txtDisp.getText() + sDigit);
repaint();
}
public void doOp(int nNewOp)
{
double dDisp;
dDisp = (new Double(txtDisp.getText())).doubleValue();
switch(nNewOp)
{
case OP_NEG:
case OP_SQRT:
case OP_C:
case OP_AC:
switch(nNewOp)
{
case OP_NEG:
txtDisp.setText((new Double(-dDisp)).toString());
break;
case OP_SQRT:
txtDisp.setText((new Double(Math.sqrt(dDisp))).toString());
mbNewNumber = true;
mbDecimal = false;
break;
case OP_C:
mbNewNumber = true;
mbDecimal = false;
txtDisp.setText("0");
break;
case OP_AC:
mnOp = OP_NONE;
mbNewNumber = true;
mbDecimal = false;
mdReg = 0.0;
txtDisp.setText("0");
break;
}
break;
case OP_ADD:
case OP_SUB:
case OP_MUL:
case OP_DIV:
case OP_EQ:
switch(mnOp)
{
case OP_ADD:
mdReg = mdReg + dDisp;
break;
case OP_SUB:
mdReg = mdReg - dDisp;
break;
case OP_MUL:
mdReg = mdReg * dDisp;
break;
case OP_DIV:
mdReg = mdReg / dDisp;
break;
case OP_EQ:
case OP_NONE:
mdReg = dDisp;
break;
}
mnOp = nNewOp;
mbNewNumber = true;
mbDecimal = false;
txtDisp.setText((new Double(mdReg)).toString());
break;
}
}
}
class CalcButton extends Button
{
int mnOp;
int mnValue;
CalcButton(String sText, int nOp, int nValue)
{
super(sText);
mnOp = nOp;
mnValue = nValue;
}
public boolean action(Event evt, Object arg)
{
PocketCalc par = (PocketCalc)getParent();
if(mnOp == par.OP_NONE)
par.append(mnValue);
else
{
par.doOp(mnOp);
}
return true;
}
}
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