Program does not create an interface

I am trying to write the beginnings of a GUI, but when I run what I have so far it does nothing?? />/> Here is my code so far:

import java.awt.event.*;
import java.awt.*;
import java.util.*;
import java.io.*;
import javax.swing.*;
public class Interface implements ActionListener{
    JFrame frame = new JFrame("Interface program");
    JTextField txt1 = new JTextField(24);
    JTextArea txt2 = new JTextArea(24, 24);
    JButton b1, b2, b3;
    
    public void creata(){
    b1.addActionListener(this);
    b2.addActionListener(this);
    b3.addActionListener(this);
    frame.add(b1);
    frame.add(b2);
    frame.add(b3);
    frame.add(txt1);
    frame.add(txt2);
    frame.setLocationRelativeTo(null);
    frame.setTitle("Week 3 Interface");
    frame.setSize(72,72);
    frame.setVisible(true);
    }
    
           
    
        
    public static void main(String[] args) {
        Interface intr = new Interface();
        intr.frame.setVisible(true);
            }

     public void actionPerformed(ActionEvent ae) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
}

but like I said, it doesn't do anything....
I know it is because I am not properly calling my swing components somehow, but I cannot see it from where I am sitting, PLEASE HELP ME HERE!!!! />/>