Múltiplos estilos com OutputStream

public class TextComponentStream extends OutputStream {
    private JTextComponent textComponent;
    private Style error;

    public TextComponentStream(JTextComponent textComponent, Style error) {
        this.textComponent = textComponent;
        this.error         = error;
    }

    @Override
    public void write(final int b) throws IOException {
        write(new byte[] {(byte) b}, 0, 1);
    }

    @Override
    public void write(final byte[] b, final int off, final int len) throws IOException {
        final String str = new String(b, off, len);

        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {

                    // trava aqui!!!
                    textComponent.getDocument().insertString(textComponent.getDocument().getLength(),
                    										 str,
                    										 error);
                }
                catch (BadLocationException e) {
                	e.printStackTrace();
                }
            }
        });
    }
}

...
System.setOut(new PrintStream(new TextComponentStream(result, null)));
System.setErr(new PrintStream(new TextComponentStream(result, SwingUtils.getErrorStyle())));
...

public class SwingUtils {

	public static Style getErrorStyle()
	{
		StyleContext sc = new StyleContext();
		Style defaultStyle = sc.getStyle(StyleContext.DEFAULT_STYLE);
		Style errorStyle = sc.addStyle("error", defaultStyle);
		StyleConstants.setForeground(errorStyle, Color.red);

		return errorStyle;
	}

        ...