As discovered by automated code analysis, BasicProgressBarUI.java#getStringPlacement calls Math.round on int input, which is never a good idea, either a useless no-op or a loss of precision for values near Integer.MAX_VALUE. Maybe divide by 2.0 instead of 2?

            return new Point(x + Math.round(width/2 - stringWidth/2),
                             y + ((height +
                                 fontSizer.getAscent() -
                                 fontSizer.getLeading() -
                                 fontSizer.getDescent()) / 2));
        } else { // VERTICAL
            return new Point(x + ((width - fontSizer.getAscent() +
                    fontSizer.getLeading() + fontSizer.getDescent()) / 2),
                    y + Math.round(height/2 - stringWidth/2));