Tengo este JTextArea y se sigue expandiendo a medida que se ingresa el texto. Sé que esto parece una pregunta de repetición, pero he seguido las respuestas y no me han funcionado. También tengo un JScrollPane adjunto pero no se muestra ninguna barra de desplazamiento. Quiero que JTextArea siga siendo un tamaño constante y que se pueda desplazar. Por favor, mire mi código y dígame lo que está mal, ¡porque no tengo idea!

Aquí está mi código:

package com.robot;

import java.awt.Dimension;
import java.awt.Toolkit;
import javax.swing.*;

public class GUI extends JFrame implements Runnable {

//start of the constructor method for GUI
public GUI() {

    //defines the line break
    String newline = System.getProperty("line.separator");

    //defines objects
    Toolkit tk = Toolkit.getDefaultToolkit();
    Dimension dim = tk.getScreenSize();

    //sets the size of the GUI
    this.setSize(600, 400);

    //centers the GUI
    int xPos = (dim.width / 2) - (this.getWidth() /2);
    int yPos = (dim.height / 2) - (this.getHeight() /2);

    this.setLocation(xPos, yPos);

    //makes the program unable to be resized
    this.setResizable(false);

    //allows the user to close the program with the x button
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    //sets the title of the program
    this.setTitle("ROBOT Alpha Alfred Version 3.0");

    //creates panels to hold the elements of the GUI
    JPanel mainPanel = new JPanel();
    JPanel buttonPanel = new JPanel();
    JPanel consolePanel = new JPanel();

    //creates buttons
    JButton runDemo = new JButton("Run Demo");
    JButton runLive = new JButton("Run Live");
    JButton scan = new JButton("Scan Market");
    JButton findPatterns = new JButton("Find Patterns");
    JButton cleanFolder = new JButton("Clean Up Folder");
    JButton configureSettings = new JButton("Configure Settings");

    //creates the console
    JTextArea console = new JTextArea(6, 40);

    //sets the default text of the console
    console.setText("----------------------- ROBOT Console -----------------------" + newline);

    //makes the console unable to be edited
    console.setEditable(false);
    console.append("3sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs22323sfasfs\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline\nline123");

    //sets the line wrapping of the console
    console.setLineWrap(true);
    console.setWrapStyleWord(true);
    JScrollPane scrollBar = new JScrollPane(console);
    scrollBar.setVerticalScrollBarPolicy(ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED);

    //adds buttons to the buttonPanel
    buttonPanel.add(runDemo);
    buttonPanel.add(runLive);
    buttonPanel.add(scan);
    buttonPanel.add(findPatterns);
    buttonPanel.add(cleanFolder);
    buttonPanel.add(configureSettings);

    //adds the console to the console panel
    consolePanel.add(console);
    consolePanel.add(scrollBar);

    //adds panels to the main panel
    mainPanel.add(buttonPanel);
    mainPanel.add(consolePanel);

    //adds the main panel to the frame
    this.add(mainPanel);

    //sets the GUI to be visible
    this.setVisible(true);

}

public void run() {

}

}

Muchas gracias!