AddNew.java

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;

public class AddNew {
    // Components
    private JFrame f;
    private JPanel p1;
    private JPanel p2;
    private JPanel p3;
    private JPanel p4;
    private JPanel p5;

    private JLabel l1;
    private JLabel l2;
    private JLabel l3;
    private JLabel l4;

    private JTextField t1;
    private JTextField t2;
    private JTextField t3;
    private JTextField t4;

    private JButton back;
    private JButton submit;
    private JButton clear;
    //. Components

    public AddNew(){
        f = new JFrame("Add New | Address Book");
        f.setLayout(new FlowLayout(FlowLayout.RIGHT));
        f.setSize(350, 500);
        f.setLocationRelativeTo(null);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // Panels
        p1 = new JPanel();
        p2 = new JPanel();
        p3 = new JPanel();
        p4 = new JPanel();
        p5 = new JPanel();
        //. Panels

        // Labels
        l1 = new JLabel("Name:");
        l2 = new JLabel("Phone:");
        l3 = new JLabel("Email:");
        l4 = new JLabel("Street Address:");
        //. Labels

        // Text Fields
        t1 = new JTextField(20);
        t2 = new JTextField(20);
        t3 = new JTextField(20);
        t4 = new JTextField(20);
        //. Text Fields

        // Buttons
        back = new JButton("Back");
        clear = new JButton("Clear");
        submit = new JButton("Submit");
        //. Buttons

        // Back Button Action
        back.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                new AddressBook();
                f.setVisible(false);
            }
        });
        //. Back Button Action

        // Clear Button Action
        clear.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                t1.setText("");
                t2.setText("");
                t3.setText("");
                t4.setText("");
            }
        });
        //. Clear Button Action

        // Submit Button Action
        submit.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                try {
                    FileWriter fw = new FileWriter("Contacts.txt", true);
                    BufferedWriter bw = new BufferedWriter(fw);

                    String name = t1.getText();
                    String phone = t2.getText();
                    String email = t3.getText();
                    String address = t4.getText();

                    bw.write(name+"\t"+phone+"\t"+email+"\t"+address+"\n");
                    bw.close();
                } catch (IOException ex) {
                    ex.printStackTrace();
                }
                finally {
                    new AddressBook();
                    f.setVisible(false);
                }
            }
        });
        //. Submit Button Action

        // Adding Components to Frame
        p1.add(l1);
        p1.add(t1);
        p2.add(l2);
        p2.add(t2);
        p3.add(l3);
        p3.add(t3);
        p4.add(l4);
        p4.add(t4);
        p5.add(back);
        p5.add(clear);
        p5.add(submit);

        f.add(p1);
        f.add(p2);
        f.add(p3);
        f.add(p4);
        f.add(p5);
        //. Adding Components to Frame

        f.setVisible(true);
    }

    public static void main(String[] args) {
        new AddNew();
    }
}