To simplify the job of presenting instructions on dialogs, I wrote a
static helper function:

public JComponent instructions (String string) {
    JTextArea ta = new JTextArea(string);
    ta.setEditable(false);
    ta.setOpaque(false); // Otherwise it has white background.
    ta.setBorder(BorderFactory.createBevelBorder(BevelBorder.LOWERED));
    return ta;
}

With a fairly long instruction string (176 characters) I unfortunately
got a very long and narrow text area with all of the text on one line.

OK, I decided, if the screen is wide enough it makes the text area long
and thin instead of wrapping. Let's see, is there anything in the
JTextArea API that might help force earlier wrapping? Yes, there is!

    ta.setColumns(60);

Only problem is, it didn't work.

A little digging around revealed that JTextArea has some unbelievably
boneheaded defaults, which are fixed with:

    ta.setLineWrap(true);
    ta.setWrapStyleWord(true);

Now the instruction boxes look great, and the dialog boxes look
terrible: the row of buttons at the bottom is cut in half horizontally
by the window bottom. The JFrames/JDialogs are packing incorrectly
whenever the JTextArea text wraps to use two lines; the windows are
being made too short by exactly one line.

Why is this happening? I have frame.pack() after the JTextArea has all
of its properties set, including setLineWrap and setWrapStyleWord as
well as the text, and after it's been added, directly or indirectly, to
the frame's component tree. So the JTextArea should be calculating its
minimum dimensions correctly, and the frame.pack() should be taking this
into account, but instead it's still treating the JTextArea as if it
were only one line high.

What gives?