Need Help, Java Beginners Applet

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ashok

need help,
October 29, 2007 at 4:15 PM

import java.awt.*;
import java.awt.event.*;
import java.applet.*;

public class CalculatorApplet extends Applet implements ActionListener
{
private Button keysArray[];
private Panel keyPad;
private TextField lcdField;
private double result;
private boolean first;
private boolean foundKey;
static boolean clearText;
private int prevOperator;

public void init()
{
lcdField = new TextField(20);
keyPad = new Panel ();
keysArray = new Button[17];
result = 0.0;
prevOperator = 0;
first = true;
clearText = true;

setLayout(new BorderLayout());

lcdField.setEditable(false);

for (int i = 0; i <=9; i++)
keysArray[i] = new Button(String.valueOf(i));
keysArray[10] = new Button("/");
keysArray[11] = new Button("*");
keysArray[12] = new Button("-");
keysArray[13] = new Button("+");
keysArray[14] = new Button("=");
keysArray[15] = new Button(".");
keysArray[16] = new Button("CLR");

keyPad.setLayout(new GridLayout (4,4));

for (int i = 7; i <=10; i++)
keyPad.add(keysArray[i]);

for (int i = 4; i <6; i++)
keyPad.add(keysArray[i]);

keyPad.add(keysArray[11]);

for (int i = 1; i <= 3;i++)
keyPad.add(keysArray[i]);

keyPad.add(keysArray[12]);

keyPad.add(keysArray[0]);

for (int i = 15; i >=13; i--)
keyPad.add(keysArray[i]);

add(lcdField, BorderLayout.NORTH);
add(keyPad, BorderLayout.CENTER);
add(keysArray[16], BorderLayout.EAST);

for(int i = 0; i < keysArray.length; i++)
keysArray[i].addActionListener(this);
}

public void actionPerformed(ActionEvent e)
{
foundKey = false;

for (int i = 0; i < keysArray.length && !foundKey; i++)
if(e.getSource() == keysArray[i])
{
foundKey = true;
switch(i)
{
case 0: case 1: case 2: case 3: case 4:
case 5: case 6: case 7: case 8: case 9:
case 15:
if (clearText)
{
lcdField.setText("");
clearText = false;
}
lcdField.setText(lcdField.getText() +
keysArray[i].getLabel());
break;

case 10:
case 11:
case 12:
case 13:
case 14:
clearText = true;
if (first)
{
if(lcdField.getText().length()==0)
result = 0.0;
else
result = Double.valueOf(lcdField.getText()).doubleValue();

first = false;
prevOperator = i;
}
else
{
switch(prevOperator)
{
case 10:
result /= Double.valueOf(lcdField.getText()).
doubleValue();
break;
case 11:
result *= Double.valueOf(lcdField.getText()).
doubleValue();
break;
case 12:
result -= Double.valueOf(lcdField.getText()).
doubleValue();
break;
case 13:
result += Double.valueOf(lcdField.getText()).
doubleValue();
break;
}
lcdField.setText(Double.toString(result));
if (i==14)
first = true;
else
prevOperator = i;
}
break;

case 16:
clearText = true;
first = true;
lcdField.setText("");
result = 0.0;
prevOperator = 0;
break;
}
}
}
}

whenever i try to run this or other applets
this msg is shown:

Exception in thread "main" java.lang.NoSuchMethodError: main

although there is no error found at the time of compilation.
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