Hello,

I'm having a problem with a JTextArea that I have inside a JScrollPane
where the scroll bar gets added/resized fine to accomodate more
information in the underlying JTextArea, but never shrinks back again
or goes away as the information in the JTextArea is removed.  The
document associated with the JTextArea is constantly having text added
and removed from it, so the number of lines it takes in the JTextArea
are constantly changing.

Periodically I execute the following code to make sure that the number
of rows in the JTextArea are sufficient to display all of the text in
the underlying document:

     if(myTextArea.getRows()!=myTextArea.getLineCount())
    myTextArea.setRows(myTextArea.getLineCount()+2);
     pack();

getLineCount supposedly returns the number of lines in the underlying
document, and if that is different than the number of rows in the
JTextArea I update the number of rows.  The '+2' is a hack because I
could never get the most recently added text at the bottom of the
document/JTextArea to display otherwise (maybe related to the other
problem which I'm getting to?).

So, finally the details of the problem:  When the above code causes
the JTextArea to be bigger than it was before (more rows), the
JScrollPane correctly adds or adjusts the vertical scroll bar to allow
scrolling to anywhere in the displayed document.  When the code above
causes the JTextArea to become smaller (less rows), the vertical
scroll bar in the JScrollPane remains exactly the same as it was
before, allowing the user to scrolldown and see lots of empty space
below the bottom of what is actually in the JTextArea.

Does anybody have any clue what I'm doing wrong here?  Is there
something besides  pack() I should be calling on the top level frame
to get the JScrollPane to notice that the JTextArea is smaller and it
should resize its vertical scroll bar?  Or, is there some way to make
the JTextArea automatically have the same number of rows as the
underlying document, avoiding the need to set the rows in the
JTextArea myself?  Right now if I leave out the above code the
JTextArea always stays the same size and the scrollbar never appears.

Any solutions, pointers or suggestions appreciated.  If there is
relevant information I'm not providing, feel free to ask and I'll try
and provide it.

-Brad