Scroll position and JTextArea

Question

I hava a JFrame with a JScrollPane/JTextArea in it.
I frequently update the textarea with a setText(string), but for every update the scrollbar jumps to the bottom. The things is that I want the scrollbar to remember its position and not change its position after an update.
The string in setText varies in length.
Any ideas, please.
Thanks!!

Answer 1

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ScrollingTest {
  static JTextArea textArea;
  static int updateCount = 0;
  static int i;
  public static void main(String[] args) {
    JButton button = new JButton("add data");
    button.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        updateDisplay();
    JPanel panel = new JPanel();
    panel.add(button);
    textArea = new JTextArea();
    textArea.setMargin(new Insets(10,10,10,10));
    textArea.setLineWrap(true);
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.getContentPane().add(panel, "North");
    f.getContentPane().add(new JScrollPane(textArea));
    f.setSize(400,300);
    f.setLocation(400,300);
    f.setVisible(true);
  private static void updateDisplay() {
    String text = "";
    for(i = updateCount; i < 40 + updateCount; i++)
      text += String.valueOf(i) + "\n";
    int caretPosition = textArea.getDocument().getLength();
    textArea.setText(textArea.getText() + text);
    updateCount = i;
    textArea.setCaretPosition(caretPosition);
}