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Can't left align a JLabel within a JPanel when adding to a BorderLayout

This seems like a simple thing to do, but I can't get it to work.
I have a BorderLayout. I want to use the top part for a title bar. I want to add a JPanel with labels, buttons and other components. However, the PAGE_START part of the border layout won't left align the panel. Here's the situation, with comments in where I've tried to set the alignment.
I noticed that when I don't add a panel to the border layout, and just write the JLabel straight in, it has left alignment by default.
This is not what I want, though, because I am planning on putting a BoxLayout.X_AXIS horizontally through the BorderLayout.PAGE_START title area. Seems to be a reasonable thing to do?
The Container pane argument to the static method is just the single panel on the main JFrame.
public static void addComponentsToPane(Container pane)
{
JLabel jlabel = new JLabel("I want to left align this inside a JPanel");
// Doesn't work: jlabel.setAlignmentX(Component.LEFT_ALIGNMENT);
JPanel jpanel = new JPanel();
//Doesn't work: jlabel.setAlignmentX(Component.LEFT_ALIGNMENT);
jpanel.add(jlabel);
pane.add(jpanel, BorderLayout.PAGE_START);
// Other parts of the BoxLayout (works fine)
JButton button = new JButton("Button 2 (CENTER)");
button.setPreferredSize(new Dimension(200, 100));
pane.add(button, BorderLayout.CENTER);
button = new JButton("Button 3 (LINE_START)");
pane.add(button, BorderLayout.LINE_START);
button = new JButton("Long-Named Button 4 (PAGE_END)");
pane.add(button, BorderLayout.PAGE_END);
button = new JButton("5 (LINE_END)");
pane.add(button, BorderLayout.LINE_END);
}
Even when I tell the panel to left align the label, it doesn't appear left aligned.
Does anyone know what I am doing wrong?

By default a JPanel uses a FlowLayout with "center" alignment.
if you want components "left" aligned, then you need to set the layout on the panel to use a FlowLayout with "left" alignment.
Read the FlowLayout API for the proper constructor to use to set the alignment.
Or you can also read the Swing tutorial on How to Use FlowLayut which gives the constructors and valid values to specify the alignment.

Set height but not width of JTextArea

I have multiple JTextAreas inside a JPanel. I am using a BoxLayout to make them align vertically and fill the width of the container.
It works, but they seem to expand to fill the entire height as well.
What I really want is simple - a text area that wraps text where I can control the width but allow the height to scale dynamically as more lines are added. The above method was just my best attempt at it. If there is a solution that uses a different layout manager, different text component, etc, that works.
minimal verifiable example below:
public static void main(String[] args) {
JFrame frame = new JFrame();
frame.setPreferredSize(new Dimension(300, 300));
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
JPanel textAreas = new JPanel();
textAreas.setLayout(new BoxLayout(textAreas, BoxLayout.Y_AXIS));
JTextArea area1 = new JTextArea();
area1.append("this is a string");
area1.setLineWrap(true);
area1.setWrapStyleWord(true);
textAreas.add(area1);
JTextArea area2 = new JTextArea("and another that is much longer, so that it wraps to the next line");
area2.setLineWrap(true);
area2.setWrapStyleWord(true);
textAreas.add(area2);
JScrollPane scrollPane = new JScrollPane();
scrollPane.setViewportView(textAreas);
frame.add(scrollPane);
frame.pack();
frame.setVisible(true);
}
I have done research on this topic on my own, including looking at different layout managers (http://docs.oracle.com/javase/tutorial/uiswing/layout/visual.html), and checking other questions on the site, but I haven't had much luck.
TLDR: Can I make it so each element of a layout has a height that scales to its content but a fixed width? If so how?

What I really want is simple - a text area that wraps text where I can control the width but allow the height to scale dynamically as more lines are added.
The BoxLayout respects the maximum size so the text area grows to fill all the space available in the panel. You can override the getMaximumSize() method to return the preferred height by using something like:
JTextArea area1 = new JTextArea()
{
public Dimension getMaximumSize()
{
Dimension d = super.getMaximumSize();
d.height = getPreferredSize().height;
return d;
}
};
It works...
Not really. Make the frame wider and the text will unwrap. Then shrink the frame and the scrollbar will appear. That is the text will not wrap again
What you need to do is force the panel added to the scroll pane to be the same width as the viewport. This will allow wrapping to work properly.
You do this by implementing the Scrollable interface on the panel. Specifically you need to override the getScrollableTracksViewportWidth() method to return true.
Or an easier solution is to use the Scrollable Panel class which allows you to set properties of the panel to control this behaviour.
You can replace a JPanel with the ScrollablePanel:
//JPanel textAreas = new JPanel();
ScrollablePanel textAreas = new ScrollablePanel();
textAreas.setScrollableWidth( ScrollablePanel.ScrollableSizeHint.FIT );
Edit:
If there is a solution that uses a different layout manager
Without overriding the getMaximumSize() method of the text areas and when using the Scrollable Panel you should be able to use the following layout managers.
The GridBagLayout allows you to specify the "weightx" constraint. This will allow the component to fill all the available space in the panel.
Or if you don't like specifying all the constrains of the GridBagLayout you could use the Relative Layout which support vertical/horizontal layout of components at their preferred size.
You would just need to use the following to force the component to fill the horizontal space:
//textAreas.setLayout(new BoxLayout(textAreas, BoxLayout.Y_AXIS));
RelativeLayout rl = new RelativeLayout(RelativeLayout.Y_AXIS);
rl.setFill( true );
textAreas.setLayout(rl);

How do I force BoxLayout and JScrollPane to restrict content size?

I encountered an issue when using a JTextField within a BoxLayout within a JScrollPane.
The desired result is a JTextField that scrolls within itself, as you see when you paste a URL that is longer than the width of your screen into the address bar on your web browser. The entire string shifts left or right when you try to move the caret past the boundaries of the text field.
However, when put in a JScrollPane, the text field fails to do this, instead expanding to fit the entire string.
Before the text:
After the text:
The text box increases its width, causing a scroll bar to appear, rather than "internal scrolling" behavior I described before (where the text box remains the same size, but only shows part of the text).
This behavior even occurs when setting the scroll bar policy to JScrollPane.HORIZONTAL_SCROLLBAR_NEVER:
I noticed that the text box performs the "internal scrolling" correctly until the window is resized, at which time the text field resizes itself off the screen.
I require a scroll pane because I need the vertical scroll bar in my application, but I would like the horizontal axis to be restricted to whatever size the window allows to the panel. How can I achieve this?
Code segment for the above examples:
import java.awt.Dimension;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextField;
public class GUI {
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel panel = new JPanel();
JScrollPane scrollPane = new JScrollPane(panel);
frame.add(scrollPane);
JTextField textField = new JTextField();
panel.add(textField);
frame.setSize(500, 200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
panel.setLayout(new BoxLayout(panel, BoxLayout.X_AXIS));
// max width = Short.MAX_VALUE so it expands to fill the frame width
// max height = preferred height so the text area height does not expand
textField.setMaximumSize(new Dimension(Short.MAX_VALUE, textField.getPreferredSize().height));
frame.setVisible(true);
}
}
The best solution would still implement a horizontal scroll bar if the combined minimum size of the components in the panel (on the horizontal axis) was greater than the width of the window (say, if I added a button in there to the left of the text field).

Use a different layout manager, something like GridBagLayout, which will generally honor the preferred size of the component, for example
JFrame frame = new JFrame();
JPanel panel = new JPanel(new GridBagLayout());
JScrollPane scrollPane = new JScrollPane(panel);
frame.add(scrollPane);
GridBagConstraints gbc = new GridBagConstraints();
gbc.weightx = 1;
gbc.fill = gbc.HORIZONTAL;
JTextField textField = new JTextField(10);
panel.add(textField, gbc);
frame.setSize(500, 200);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);

A simple solution is to set the preferred width of the text field to its minimum width.
textField.setPreferredSize(new Dimension(textField.getMinimumSize().width, textField.getPreferredSize().height));
The text field will perform the "internal scrolling" behavior, as well as cause a scroll bar to appear if the window shrinks below its minimum size (as described in the original question's final statement, below)
The best solution would still implement a horizontal scroll bar if the combined minimum size of the components in the panel (on the horizontal axis) was greater than the width of the window (say, if I added a button in there to the left of the text field).

center a panel in a box layout row in java

I have this code below to create a page inside of a tab.
I want each layout in one row of the overall box layout but i want the elements to stay in their original size and not expand to fill the width of the overall window. does anyone know what lines of code i need to change or what is the best way of doing this?! The image attached shows what it looks like at the moment
public void createPage4() {
panel4 = new JPanel();
panel4.setLayout(new BoxLayout(panel4, BoxLayout.Y_AXIS));
navigatePanel = new JPanel();
navigatePanel.setLayout(new BoxLayout(navigatePanel, BoxLayout.X_AXIS));
previousButton.setText("Previous");
previousButton.setEnabled(false);
navigatePanel.add(previousButton);
navigatePanel.add(Box.createHorizontalStrut(10));
indexTextField.setHorizontalAlignment(JTextField.CENTER);
navigatePanel.add(indexTextField);
navigatePanel.add(Box.createHorizontalStrut(10));
ofLabel.setText("of");
navigatePanel.add(ofLabel);
navigatePanel.add(Box.createHorizontalStrut(10));
maxTextField.setHorizontalAlignment(JTextField.CENTER);
maxTextField.setEditable(false);
navigatePanel.add(maxTextField);
navigatePanel.add(Box.createHorizontalStrut(10));
nextButton.setText("Next");
nextButton.setEnabled(false);
navigatePanel.add(nextButton);
panel4.add(navigatePanel);
displayPanel = new JPanel();
displayPanel.setLayout(new GridLayout(5, 2, 4, 4));
firstNameLabel.setText("First Name:");
displayPanel.add(firstNameLabel);
displayPanel.add(firstNameTextField);
lastNameLabel.setText("Last Name:");
displayPanel.add(lastNameLabel);
displayPanel.add(lastNameTextField);
panel4.add(displayPanel);
}
image

BoxLayout accepting Min, Max and PreferredSize that came from JComponents
I want each layout in one row of the overall box layout but i want the elements to stay in their original size and not expand to fill the width of the overall window
I'd be to use proper LayoutManager, FlowLayout accepting only PreferredSize, and/or all JComponents layed by GridBagLayout without defininitions of GridBagConstraints stays unchanged on containers resize
doesn't make me sence (my view) for why reason (sure this is your job), but for better help sooner post an SSCCE

The easiest way is to add your panel4 to an other panel that uses GridBagLayout and then add that panel to the container. Then it will be centered and nothing will stretch on resize.
JPanel centeredPanel = new JPanel(new GridBagLayout());
centeredPanel.add(panel4); // add this panel to the container
You should also construct the textfields with a specified number of columns, like
indexTextField = new JTextField(20);

Getting appropriate dimensions of a Swing component

I was trying out JLayeredPane. So, in the following code, I created a JLayeredPane and a JLabel. I added the label to the layered pane, which I added to a JPanel. This panel was then added to a JFrame.
public static void main(String[] args) {
frame = new JFrame("LayeredPane Example");
frame.setPreferredSize(new Dimension(500,500));
layeredPane = new JLayeredPane();
layeredPane.setPreferredSize(new Dimension(400, 400));
JLabel label = new JLabel("Label on LayeredPane");
label.setLocation(200, 200);
System.out.println("Width " + label.getWidth() );
label.setBounds(20, 20, 400, 40);
layeredPane.add(label);
layeredPane.setLayer(label, 10, 1);
frame.setLayout(new BorderLayout());
JPanel panel = new JPanel();
panel.add(layeredPane);
frame.add(panel);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
Now the problem is that if I do not have the statement label.setBounds(20, 20, 400, 40);, then the label does not appear on the layered pane. This raises two questions:
Why is setBounds so important?
Probably a part of my previous questions answer, the label had an initial height and width of 0 before setting bounds, which might be the reason setBounds is important. In that case, I want to know how can I determine appropriate bounds for a Swing component when I am adding it to a JLayeredPane. (If my bounds are less than the appropriate size of the component, the component will appear hidden)
Edit:
The first question was answered earlier in more detail here.

Regarding:
Why is setBounds so important: A JLayeredPane uses essentially a null layout, and whenever you use null layouts, you the coder are completely responsible for both the size and position of the components that you add. That's simply the rules of this layout.
How to determine the appropriate bounds: One thing I've done is simply to let the component tell me what its preferredSize is and then use it for its size:
myJLabel.setSize(myJLabel.getPreferredSize());
Another thing I've done is to use non-opaque JPanels for each layer of my JLayeredPane, give these JPanels appropriate layouts and then add my components to the appropriate layer JPanel. I then use a listener to be sure that the layer JPanel's size matches that of its JLayeredPane container.