Set font color to JTextPane

Question

I wrote a small program only 70 lines. These codes traverse all the text line by line, show all digits in blue color, but I do not know why, you see, there is something wrong, some characters are not updated correctly. but why?
import javax.swing.*;
import java.awt.Color;
import javax.swing.text.*;
public class MainWnd extends JFrame{
private JTextPane textPane = new JTextPane();
public MainWnd() {
getContentPane().add(textPane);
textPane.setText("1234567890\r\n1234567890\r\n1234567890\r\n1234567890\r\n1234567890\r\n");
setBounds(100, 100, 400, 400);
formatHighlight(textPane);
show();
public void formatHighlight(JTextPane textPane) {
String text = textPane.getText();
int begin = 0;
int end = text.length() - 1;
System.out.println("First, set all text black color: begin:" + begin + " end:" + end);
System.out.println("All text is #" + text.substring(begin, end + 1)+"#");
//reset all as default color black
setTextColor(textPane, begin, end + 1, Color.BLACK);
for (int i = begin; i <= end; ) {
char c = text.charAt(i);
//digital
if (Character.isDigit(c)) {
i = transactDigit(textPane, text, i);
continue;
//others
System.out.println("skip others at i:" + i + " c:" + c);
i++;
private void setTextColor(final JTextPane sourcePane,
final int offset, final int endPos, final Color color) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
MutableAttributeSet attr = new SimpleAttributeSet();
StyleConstants.setForeground(attr, color);
if (offset != endPos) {
StyledDocument doc = (StyledDocument) sourcePane.getDocument();
doc.setCharacterAttributes(offset, endPos - offset, attr, false);
private int transactDigit(JTextPane sourcePane, String text, int offset) {
int endPos = 0;
for (endPos = offset; endPos < text.length(); endPos++) {
char c = text.charAt(endPos);
if (!Character.isDigit(c))
break;
System.out.println("set digit blue color from " + offset + " to " + (endPos-1));
System.out.println("The digit string is #" + text.substring(offset, endPos) + "#");
setTextColor(sourcePane, offset, endPos, Color.BLUE);
return endPos;
public static void main(String[] args) {
MainWnd mainWnd = new MainWnd();
Pls, help!

Answer 1

I have found the reason. replace
String text = textPane.getText();
with
String text = textPane.getDocument().getText(0, textPane.getDocument().getLength());
It's because the document (model) does not contain '\r', but the view does.
Thx for your enthusiasm.