JPanel BoxLayout nested JPanel alignment issue

[RagingRiver]

I am having a problem with left alignment after adding a second JPanel. Both JPanels are using the BoxLayout with the first set to Y_AXIS and the second set to X_AXIS. If you comment out the add(twoPanel) it results in the desired left alignment. I don't understand why the alignment changes after adding the second JPanel. Thanks in advance.

import javax.swing.*;

public class BoxManager extends JApplet{
	JButton one, two, three;
	
	public void init() {
		one = new JButton("one");
		two = new JButton("two");
		three = new JButton("three");
		
		setLayout(new BoxLayout(getContentPane(), BoxLayout.Y_AXIS));
		add(new JLabel("This is the contentPane."));
		JPanel twoPanel = new JPanel();
		twoPanel.setLayout(new BoxLayout(twoPanel, BoxLayout.X_AXIS));
		twoPanel.add(new JLabel("Second Panel"));
		twoPanel.add(new JTextField("Text Field"));
		add(twoPanel); // comment this line out
		
		add(one);
		add(two);
		add(three);
	}
}

[Ezzaral]

Try

twoPanel.setLayout(new BoxLayout(twoPanel, BoxLayout.PAGE_AXIS));

edit: Hmm, scratch that, it doesn't preserve the horizontal ordering that you wanted for the second panel.

[RagingRiver]

I solved it out by adding the following before adding the twoPanel.

twoPanel.setAlignmentX(LEFT_ALIGNMENT);

[Ezzaral]

Edit: oops cross-posted, I guess you found the same thing :)
Try this

public void init() {
		one = new JButton("one");
		two = new JButton("two");
		three = new JButton("three");

		setLayout(new BoxLayout(getContentPane(), BoxLayout.PAGE_AXIS));
		add(new JLabel("This is the contentPane."));
		JPanel twoPanel = new JPanel();
                twoPanel.setAlignmentX(Component.LEFT_ALIGNMENT);
		twoPanel.setLayout(new BoxLayout(twoPanel, BoxLayout.LINE_AXIS));
		twoPanel.add(new JLabel("Second Panel"));
		twoPanel.add(new JTextField("Text Field"));
		add(twoPanel); // comment this line out

                one.setAlignmentX(Component.LEFT_ALIGNMENT);
                two.setAlignmentX(Component.LEFT_ALIGNMENT);
                three.setAlignmentX(Component.LEFT_ALIGNMENT);
		add(one);
		add(two);
		add(three);
	}