java读取jpg图片旋转按比例缩放

//入口
public static BufferedImage constructHeatWheelView(int pageWidth, int pageHeight, DoubleHolder scaleHolder) throws ValidateException{
     
        BufferedImage bi = new BufferedImage(pageWidth, pageHeight, BufferedImage.TYPE_INT_RGB);
        Graphics2D g = (Graphics2D) bi.getGraphics();
        DrawingHelper.clearGraphics(g, pageWidth, pageHeight);
        try {
        
            //1 读取 jpg 格式图片
            Image srcImage= ImageIO.read(ECSigleton.getInstance().getAppManager().loadImageStream("HeatWheel"));
            
            //2   旋转 Image
            bi=getImage_rote270(srcImage);
            //3 按比例缩放
            bi=scale(bi,0.75);
             
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }                
        return bi;    
    }
    
 public static BufferedImage getImage_rote270(Image img)
    {
        int width = img.getWidth(null);
        int height = img.getHeight(null);
        BufferedImage newImg = new BufferedImage(height, width, 1);
        Graphics g = newImg.getGraphics();
        Graphics2D g2d = (Graphics2D) g;
        g2d.rotate(Math.toRadians(-90), 0, 0);
        g2d.drawImage(img, -width, 0, width, height,  null);
        g2d.dispose();
        return newImg;
    }
    
    public static BufferedImage  scale(BufferedImage src,  double scale) {
             
            int width = src.getWidth(); // 得到源图宽
            int height = src.getHeight(); // 得到源图长
         
                width = (int)(width * scale);
                height = (int)(height * scale);
             
            Image image = src.getScaledInstance(width, height,
                    Image.SCALE_DEFAULT);
            BufferedImage tag = new BufferedImage(width, height,
                    BufferedImage.TYPE_INT_RGB);
            Graphics g = tag.getGraphics();
            g.drawImage(image, 0, 0, null); // 绘制缩小后的图
            g.dispose();
            //ImageIO.write(tag, "JPEG", new File(result));// 输出到文件流
        return tag;
    }