tester with buttons

package Phone;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.io.IOException;

import javax.swing.AbstractAction;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import java.awt.Component;

public class Tester extends JFrame {

    public  Tester()
    {

        setTitle("main");
        setSize(800,800);

        MyAction myAct = new MyAction("Print a new Customer");
        JButton btn1 = new JButton(myAct);
        btn1.setFont(new Font("Arial",Font.BOLD,40));

        JButton btn2 = new JButton(myAct);
        JButton btn3 = new JButton(myAct);

        setLayout(new BorderLayout());
        add(btn1, BorderLayout.CENTER);
        add(btn2, BorderLayout.EAST);
        add(btn3, BorderLayout.WEST);
    }

    public static void main(String[] args) {
        new Tester().setVisible(true);


    }
    public class MyAction extends AbstractAction {

        public MyAction(String str){
            super(str);
        }

        public void actionPerformed(ActionEvent arg0){
            JOptionPane.SELECTION_VALUES_PROPERTY.valueOf(NAME);

            try{
                Phone p = new Phone ("d:\\cust.txt","0508848987", "jackov jojo", (int) Math.ceil(Math.random() * 1000));
                }catch (StackOverflowError | IOException e) {
                    e.initCause(null);
                }
        }
}}