java 图片旋转

    import java.awt.Color; 
    import java.awt.Graphics2D; 
    import java.awt.Transparency; 
    import java.awt.geom.AffineTransform; 
    import java.awt.image.AffineTransformOp; 
    import java.awt.image.BufferedImage; 
    import java.io.ByteArrayInputStream; 
    import java.io.ByteArrayOutputStream; 
    import java.io.IOException; 
    import java.io.InputStream; 
     
    import javax.imageio.ImageIO; 
    import javax.imageio.stream.ImageOutputStream; 
     
    public class ImageChange { 
     
        public static InputStream rotateImg(BufferedImage image, int degree, Color bgcolor) throws IOException { 
     
            int iw = image.getWidth();//原始图象的宽度  
            int ih = image.getHeight();//原始图象的高度 
            int w = 0; 
            int h = 0; 
            int x = 0; 
            int y = 0; 
            degree = degree % 360; 
            if (degree < 0) 
                degree = 360 + degree;//将角度转换到0-360度之间 
            double ang = Math.toRadians(degree);//将角度转为弧度 
     
            /**
             *确定旋转后的图象的高度和宽度
             */ 
     
            if (degree == 180 || degree == 0 || degree == 360) { 
                w = iw; 
                h = ih; 
            } else if (degree == 90 || degree == 270) { 
                w = ih; 
                h = iw; 
            } else { 
                int d = iw + ih; 
                w = (int) (d * Math.abs(Math.cos(ang))); 
                h = (int) (d * Math.abs(Math.sin(ang))); 
            } 
     
            x = (w / 2) - (iw / 2);//确定原点坐标 
            y = (h / 2) - (ih / 2); 
            BufferedImage rotatedImage = new BufferedImage(w, h, image.getType()); 
            Graphics2D gs = (Graphics2D)rotatedImage.getGraphics(); 
            if(bgcolor==null){ 
                rotatedImage  = gs.getDeviceConfiguration().createCompatibleImage(w, h, Transparency.TRANSLUCENT); 
            }else{ 
                gs.setColor(bgcolor); 
                gs.fillRect(0, 0, w, h);//以给定颜色绘制旋转后图片的背景 
            } 
             
            AffineTransform at = new AffineTransform(); 
            at.rotate(ang, w / 2, h / 2);//旋转图象 
            at.translate(x, y); 
            AffineTransformOp op = new AffineTransformOp(at, AffineTransformOp.TYPE_BICUBIC); 
            op.filter(image, rotatedImage); 
            image = rotatedImage; 
             
            ByteArrayOutputStream  byteOut= new ByteArrayOutputStream(); 
            ImageOutputStream iamgeOut = ImageIO.createImageOutputStream(byteOut); 
             
            ImageIO.write(image, "png", iamgeOut); 
            InputStream  inputStream = new ByteArrayInputStream(byteOut.toByteArray()); 
             
            return inputStream; 
        } 

         
    }