New to Java

I am making a calculator for my school project and i finished and it doesn't give me the result. there isent a = button you insert your number and then you push the opperation that you want to do. please help me its due on friday.

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Calculator extends JFrame {

JButton add ,subtract, multiply, divide;
JTextField num1 , num2 ;
JLabel result , enter1 , enter2 ;

public Calculator () {
setLayout (new GridBagLayout());
GridBagConstraints c = new GridBagConstraints ();

enter1 = new JLabel ("lst: ");
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 0;
c.gridy = 0;
add(enter1,c);

num1 = new JTextField(10);
c.fill = GridBagConstraints.HORIZONTAL;
c.gridx = 1;
c.gridy = 0;
c.gridwidth = 3;
add(num1 , c ) ;

enter2 = new JLabel ("2nd: ") ;
c.fill = GridBagConstraints.HORIZONTAL ;
c.gridx = 0;
c.gridy = 1;
c.gridwidth = 1;
add (enter2 , c ) ;

num2 = new JTextField(10);
c.fill = GridBagConstraints.HORIZONTAL ;
c.gridx = 1;
c.gridy = 1;
c.gridwidth = 3;
add (num2 , c ) ;

add = new JButton ("+");
c.fill = GridBagConstraints.HORIZONTAL ;
c.gridx = 0;
c.gridy = 2;
c.gridwidth = 1;
add (add , c ) ;

subtract = new JButton ("-") ;
c.fill = GridBagConstraints.HORIZONTAL ;
c.gridx = 1;
c.gridx = 2;
add (subtract , c ) ;

multiply = new JButton ("*") ;
c.fill = GridBagConstraints.HORIZONTAL ;
c.gridx = 2;
c.gridy = 2;
add (multiply , c );

divide = new JButton ("/");
c.fill = GridBagConstraints.HORIZONTAL ;
c.gridx = 3;
c.gridy = 2;
add (divide , c);

result = new JLabel("");
c.fill = GridBagConstraints.HORIZONTAL ;
c.gridx = 0;
c.gridy = 4;
c.gridwidth = 4;

event a = new event () ;
add.addActionListener(a) ;
subtract.addActionListener(a) ;
multiply.addActionListener(a) ;
divide.addActionListener(a) ;

}
public class event implements ActionListener {
public void actionPreformed (ActionEvent a) {
double number1 , number2 ;

try {
number1 = Double.parseDouble(num1.getText()) ;
} catch (NumberFormatException e) {
result.setText("Illegal Data");
result.setForeground(Color.RED) ;
return;

}
try {
number2 = Double.parseDouble(num2.getText()) ;
}catch (NumberFormatException e) {
result.setText("illegal data");
result.setForeground(Color.RED);
return;
}
String op = a.getActionCommand();

if (op.equals("+")) {
double sum = number1 + number2 ;
result.setText(number1 + "+" + number2 + "=" + sum ) ;
result.setForeground(Color.RED) ;
} else if (op.equals("-")) {
double diff = number1 - number2 ;
result.setText (number1 + "-" + number2 + "=" + diff) ;
result.setForeground(Color.RED);

} else if (op.equals("*")) {
double factor = number1 * number2 ;
result.setText (number1 + "*" + number2 + "=" + factor) ;
result.setForeground(Color.RED);

}else if (op.equals("/")) {
if (number2 == 0) {
result.setText("Cannot Divide by 0") ;
result.setForeground(Color.RED);
} else {
double quotient = number1 / number2 ;
result.setText(number1 + "/" + number2 + "=" + quotient);
result.setForeground(Color.RED);
}
}

}
}
public static void main (String args []) {
Calculator gui = new Calculator ();
gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
gui.setVisible(true);
gui.setSize(250,175);
gui.setTitle("Event Night Product!");
}
}