Make JTextArea in JList cell renderer in JScrollPane resize to scroll view width, height of content

Sorry if the title is a bit confusing. Here is the situation:

I have a JList in a JScrollPane. Each list item (implemented as a custom ListCellRenderer) contains a JFrame with some labels and most importantly, a JTextArea. The text area contains some text that needs to wrap across many lines so that the user does not need to scroll horizontally in the scroll pane. I do not want the text area to scroll by itself, I just want it to expand to take as much vertical space as it needs.

If it helps understand what I am trying to achieve, here is a screenshot from the IntelliJ swing UI designer:

I would like the body text area (and the panel with it) to expand to as much vertical space as it needs.

The component holding the text does not have to be a text area, I tried a JTextPane and that did not work either. The text does not need to be editable.

I have already set the text area to wrap (with setLineWrap and setWrapStyleWord), and disabled horizontal scrolling on the scroll pane with setHorizontalScrollBarPolicy.

Here is a minimal reproducible example:

import javax.swing.*;
import java.awt.*;
import java.util.Arrays;

public class TextAreaListTest implements ListCellRenderer<String> {
    // Arbitrary long string
    private static final String LORUM_IPSUM = """
            Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed sit amet est eget mauris tempus vehicula.
            Nunc aliquet quis mi vitae fringilla. Aliquam laoreet eu metus sit amet iaculis. Curabitur imperdiet eu est
            et lobortis. Mauris eget est id lorem iaculis dictum. Aenean nisi libero, consectetur quis enim sed,
            pulvinar facilisis erat. Aliquam euismod nulla et dictum dictum. Etiam non ullamcorper sem. Nulla efficitur,
            quam cursus molestie euismod, dui lorem congue mi, placerat blandit turpis ex id libero. Nullam sit amet
            porta purus. Mauris scelerisque justo non orci vehicula, sed mattis sapien cursus. Aenean at porttitor
            dolor. Aenean euismod massa et libero egestas, sed lacinia eros aliquet. In tincidunt vehicula ex, a
            sollicitudin justo consequat ac. In in purus ut ligula sollicitudin porta quis eu neque. Aliquam erat volutpat.
            """;

    @Override
    public Component getListCellRendererComponent(JList<? extends String> list, String value, int index, boolean isSelected, boolean cellHasFocus) {
        JTextArea textArea = new JTextArea();
        textArea.setLineWrap(true);
        textArea.setWrapStyleWord(true);
        textArea.setText(value);

        JPanel panel = new JPanel();
        BoxLayout layout = new BoxLayout(panel, BoxLayout.Y_AXIS);
        panel.setLayout(layout);
        panel.add(new JLabel("Header label"));
        panel.add(textArea);
        return panel;
    }

    public static JComponent getRootComponent() {
        DefaultListModel<String> listModel = new DefaultListModel<>();
        listModel.addAll(Arrays.asList("a short string", LORUM_IPSUM));

        JList<String> list = new JList<>();
        list.setModel(listModel);
        list.setCellRenderer(new TextAreaListTest());

        JScrollPane scrollPane = new JScrollPane(list);
        scrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
        return scrollPane;
    }

    public static void main(String[] args) {
        JFrame frame = new JFrame();
        frame.setContentPane(getRootComponent());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setVisible(true);
    }
}

This example shows the issue: Lines of the text area do wrap, however the actual height of the text area (and the parent panel) does not change, so the text that does not fit in the text area if it was was not wrapped gets cut off when it wraps.

To be clear, I would like each list item to grow in height when the window is resized (and the text area is forced to war) to fit the whole text.

Thanks in advance for any help. I've been stumped with this for a few days.

Here's a hack that almost works. I compile to the Java 8 standard.

I calculate the size of the JTextArea for each value. The calculation is a bit imprecise and depends on the preferred size of the JPanel I set in the getRootComponent method, and the font used for the text in the JTextArea.

Here's the code I tested with.

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Dimension;
import java.util.Arrays;
import javax.swing.DefaultListModel;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.ListCellRenderer;
import javax.swing.SwingUtilities;
public class TextAreaListTest implements ListCellRenderer<String> {
// Arbitrary long string
private static final String LORUM_IPSUM = "Lorem ipsum dolor sit amet, consectetur "
+ "adipiscing elit. Sed sit amet est eget mauris tempus vehicula. "
+ "Nunc aliquet quis mi vitae fringilla. Aliquam laoreet eu metus "
+ "sit amet iaculis. Curabitur imperdiet eu est et lobortis. Mauris "
+ "eget est id lorem iaculis dictum. Aenean nisi libero, consectetur "
+ "quis enim sed, pulvinar facilisis erat. Aliquam euismod nulla et "
+ "dictum dictum. Etiam non ullamcorper sem. Nulla efficitur, quam "
+ "cursus molestie euismod, dui lorem congue mi, placerat blandit "
+ "turpis ex id libero. Nullam sit amet porta purus. Mauris scelerisque "
+ "justo non orci vehicula, sed mattis sapien cursus. Aenean at porttitor "
+ "dolor. Aenean euismod massa et libero egestas, sed lacinia eros aliquet. "
+ "In tincidunt vehicula ex, a sollicitudin justo consequat ac. In in "
+ "purus ut ligula sollicitudin porta quis eu neque. Aliquam erat volutpat.";
private static JPanel rootPanel;
@Override
public Component getListCellRendererComponent(JList<? extends String> list, 
String value, int index, boolean isSelected, boolean cellHasFocus) {
int width = rootPanel.getWidth() / 6;
int lines = value.length() / width + 1;
JTextArea textArea = new JTextArea(lines, width / 2);
textArea.setLineWrap(true);
textArea.setWrapStyleWord(true);
textArea.setText(value);
JPanel panel = new JPanel();
panel.setLayout(new BorderLayout());
panel.add(new JLabel("Header label"), BorderLayout.BEFORE_FIRST_LINE);
panel.add(textArea, BorderLayout.CENTER);
return panel;
}
public static JComponent getRootComponent() {
DefaultListModel<String> listModel = new DefaultListModel<>();
listModel.addAll(Arrays.asList("A short string", LORUM_IPSUM, 
"A second short string", LORUM_IPSUM));
JList<String> list = new JList<>();
list.setModel(listModel);
list.setCellRenderer(new TextAreaListTest());
JScrollPane scrollPane = new JScrollPane(list);
rootPanel = new JPanel(new BorderLayout());
rootPanel.setPreferredSize(new Dimension(400, 400));
rootPanel.add(scrollPane, BorderLayout.CENTER);
return rootPanel;
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
JFrame frame = new JFrame("TextArea List Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(getRootComponent(), BorderLayout.CENTER);
frame.pack();
frame.setLocationByPlatform(true);
frame.setVisible(true);
}
});
}
}