How to keep a GUI running after a program is run in Java

Question

I am a high school student working on a project that will convert the video from a YouTube link into an MP3 and download it. This program opens a GUI and has a button that converts the video from the link into an MP3 and downloads it. However, after the link gets converted I want it to open up another GUI, but the program just ends. Is there any way to have the program to continue to run after the downloading process?

package com.company;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;

public class GUI extends JFrame {

    private static JTextField userLink;
    private static JFrame frameOne;
    private static JPanel panelOne;
    private static JButton convertB;
    private static JLabel titleOne;
    private static JLabel name;
    public String youtubeLink;
    public static JLabel titleTwo;
    public static JLabel info;

    public GUI() {

        panelOne = new JPanel();
        frameOne = new JFrame();
        frameOne.setSize(500, 300);
        frameOne.setBackground(Color.CYAN);

        frameOne.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frameOne.setVisible(true);
        frameOne.add(panelOne);
        panelOne.setLayout(null);

        titleOne = new JLabel("Welcome to the Youtube");      //Title for first panel
        titleOne.setBounds(55, 10, 500, 30);
        titleOne.setFont(new Font("Courier", Font.BOLD, 30));
        panelOne.add(titleOne);

        titleTwo = new JLabel("to MP3 Converter!");      //Title for first panel
        titleTwo.setBounds(100, 40, 500, 30);
        titleTwo.setFont(new Font("Courier", Font.BOLD, 30));
        panelOne.add(titleTwo);

        name = new JLabel("By Zeid Akel");
        name.setBounds(220, 80, 80, 25);
        panelOne.add(name);

        convertB = new JButton("Convert and Download");                //Convert and 
        convertB.setBounds(170, 220, 175, 50);
        convertB.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {

                youtubeLink = userLink.getText();
                System.out.println(youtubeLink);

                String s;
                String l = "youtube-dl -x --audio-format mp3 ";
                String rl = l + youtubeLink;

                File f = new File("/Users/zeidakel/YoutubeVideos");     //Location where 

                if (!f.exists()) {
                    System.out.println("Download Location does not exist");     //Check if 

                } else {

                    try {

                        Process p = Runtime.getRuntime().exec(rl); //Code put int terminal

                        BufferedReader stdInput = new BufferedReader(new InputStreamReader(p.getInputStream()));
                        BufferedReader stdError = new BufferedReader(new InputStreamReader(p.getErrorStream()));

                        System.out.println("Output:\n");
                        while ((s = stdInput.readLine()) != null) {
                            System.out.println(s);
                        }

                        System.out.println("Errors:\n");
                        while ((s = stdError.readLine()) != null) {
                            System.out.println(s);
                        }

                        frameOne.setVisible(false);
                        new GUI2();

                        System.exit(0);
                    } catch (IOException e1) {

                    }
                }

            }
        });
        panelOne.add(convertB);

        userLink = new JTextField();                         //Input area for youtube link
        userLink.setBounds(135, 190, 250, 25);
        panelOne.add(userLink);

        info = new JLabel("Paste your link here:");
        info.setBounds(140, 170, 250, 25);
        panelOne.add(info);

        frameOne.setVisible(true);

    }

    }

Answer 1

The GUI should always be running you should never close it or try to create a new JFrame.

Instead, the task to convert the video should be run in a separate Thread, so you don't prevent the GUI from responding to events.

An easy way to do this is to use a SwingWorker. Read the section from the Swing tutorail on Concurrency for more information and examples.

Other comments:

1. Swing components should NOT be defined as static variables. That is not what the static keyword is used for.

2. Don't use a null layout and setBounds(). Swing was designed to be used with layout managers.