Disappointed in JtextPane and DefaultStyledDocument (or Swing?)

Question

Hey guys,
I'm making a little IRC client to put on my website , http://www.ScriptBreaker.com. I have read a lot of documentations, who told me to use Swing and not awt because Swing is the newest, and the �best�.
First of all I can't get my JtextPane aligned at the last line, mostly there is always one or two lines beneath the displayed rectangle.
I'm using the following code to do this:
int max = this.parent.jScrollPane1.getVerticalScrollBar().getMaximum();
this.parent.jScrollPane1.getVerticalScrollBar().setValue(max);
also tried with
Rectangle visible= this.getVisibleRect();
visible.y = this.getHeight();
this.scrollRectToVisible(visible);
but same problem.
My second problem is that I see sometimes twice the same line at the bottom, until there comes a new line in, then the extra line disappears.
For example:
<sun> How are you?
<java> okidoki
<java> okidoki
<sun> How are you?
<java> okidoki
<sun> Holy ghost, I'just saw you twice.
Here is the code that I�m using to display the text into my JtextPane:
private DefaultStyledDocument doc = new DefaultStyledDocument();
private StyleContext myContext = StyleContext.getDefaultStyleContext();
private Style defstyle = myContext.getStyle(StyleContext.DEFAULT_STYLE);
private Style nick;
private Style quit;
private Style join;
private Style info;
private Style start;
private Style maction;
private client parent;
public Screen()
super() ; // extends JtextPane
// add Style definitions
public void addtext(String text, String txtnick, char action)
try {
if(action == 'q'){doc.insertString(doc.getLength(),text,quit);}
else{if(action == 'j'){doc.insertString(doc.getLength(),text,join);}
else{if(action == 'i'){doc.insertString(doc.getLength(),text,info);}
else{if(action == 's'){doc.insertString(doc.getLength(),text,start);}
else{if(action == 'a'){doc.insertString(doc.getLength(),text,maction);}
else{
doc.insertString(doc.getLength(),"<",defstyle);
doc.insertString(doc.getLength(),txtnick,nick);
doc.insertString(doc.getLength(),"> "+text,defstyle);
this.pullDown(); // function to pull the JtextPane to the last line;
catch(BadLocationException ie){}
Thanks in advance
Pieter Pareit

Answer 1

Try something like this:
    private static JTextPane display = new JTextPane();
    private static Document doc = display.getDocument();
    public static void display(String input) {
        display.setCaretPosition(display.getDocument().getLength());
        addtext(String text, String txtnick, char action)
    public void addtext(String text, String txtnick, char action){
        try {
            if(action == 'q'){doc.insertString(doc.getLength(),text,quit);}
            else{if(action == 'j'){doc.insertString(doc.getLength(),text,join);}
            else{if(action == 'i'){doc.insertString(doc.getLength(),text,info);}
            else{if(action == 's'){doc.insertString(doc.getLength(),text,start);}
            else{if(action == 'a'){doc.insertString(doc.getLength(),text,maction);}
            else{
                doc.insertString(doc.getLength(),"<",defstyle);
                doc.insertString(doc.getLength(),txtnick,nick);
                doc.insertString(doc.getLength(),"> "+text,defstyle);
        catch(BadLocationException ie){}
doc.insertString(doc.getLength(), "\n",null);
  }