上传期间如何调整照片的尺寸？

import javax.imageio.ImageIO;
import org.imgscalr.Scalr;

InputStream myPhotoInputStream = // new FileInputStream(file)
                                 // or FileItemStream.openStream(); from an HTTP upload
OutputStream outstream = ...
BufferedImage image = ImageIO.read( myPhotoInputStream );
int maxDimension = 1024;
image = Scalr.resize(image, maxDimension);
ImageIO.write(image, \"JPEG\", outstream);