问题出在哪里呢？
我的实现描述：
BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); //
Graphics2D g2 = (Graphics2D) bi.getGraphics();
g2.setBackground(new Color(255, 255, 255));
g2.clearRect(0, 0, width, height);//
g2.setFont(font); //
g2.setPaint(color); //
FontRenderContext context = g2.getFontRenderContext(); //
Rectangle2D bounds = font.getStringBounds(str, context);//
g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);//
g2.dispose();
FileOutputStream out = new FileOutputStream(sbFile);
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
encoder.encode(bi);
out.close();
