I'm having difficulty setting the size of the BoxLayout in Java Swing.

I want to change the height of the BoxLayout so one portion is 1/4 the size of the container and the other 3/4. I tried using: createVerticalStrut(getSize().height / 3); but this didn't work. Any help would be greatly appreciated. Thanks.

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import javax.swing.*;
import javax.swing.JFrame;
import java.awt.*;

import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class DrawingTool extends JFrame{
    public DrawingTool(){


        setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE); //Exits out of application
        setTitle("Shape Drawing Tool");

        paintComponents(null);
        setSize(300, 300);

        Box horizontalBox1,horizontalBox2;
        JPanel panel1,panel2;
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        Container contentPane = getContentPane();
        //contentPane.setLayout(new BoxLayout());

        horizontalBox1 = Box.createVerticalBox();
        horizontalBox1.createVerticalStrut(getSize().height / 3);

        panel1 = new JPanel(new GridLayout(0,1));
        panel1.add(horizontalBox1);
        panel1.add(Box.createHorizontalGlue());
        //horizontalBox1.
        panel1.setBorder(BorderFactory.createTitledBorder("Selection Area"));
        contentPane.add(panel1);

        horizontalBox2 = Box.createVerticalBox();
        horizontalBox2.createVerticalStrut(getSize().height / 1);
        //(getSize().height/4);
        panel2 = new JPanel(new GridLayout(0,1));
        panel2.add(horizontalBox2);
        panel2.setBorder(BorderFactory.createTitledBorder("Draw Area"));
        contentPane.add(panel2,BorderLayout.SOUTH);
        setVisible(true);
    }
    public static void main(String[] args) {
        DrawingTool dt=new DrawingTool();



    }
}

Output: https://imgur.com/a/NFZXkgE

What it's supposed to look like: https://imgur.com/a/3ssEbph