java - Manipulate an image without deleting its EXIF data -

using imageio, have problem of transforming image file, , after overwriting it, loses of exif data. there way preserve without first extracting it, caching it, , resetting it?

here solution using combination of imageio, imgscalr , apache commons-imaging. it's pity there's no single library combines reading image metadata, making rather excessive on memory usage; improvements welcome.

import java.awt.image.bufferedimage; import java.io.bytearrayinputstream; import java.io.bytearrayoutputstream; import java.io.ioexception; import java.io.inputstream; import java.io.outputstream; import javax.imageio.imageio; import org.apache.commons.imaging.imagereadexception; import org.apache.commons.imaging.imagewriteexception; import org.apache.commons.imaging.imaging; import org.apache.commons.imaging.common.iimagemetadata; import org.apache.commons.imaging.formats.jpeg.jpegimagemetadata; import org.apache.commons.imaging.formats.jpeg.exif.exifrewriter; import org.apache.commons.imaging.formats.tiff.tiffimagemetadata; import org.apache.commons.io.ioutils; import org.imgscalr.scalr;   public class imagedata {      private byte[] imagedata;       public imagedata(inputstream instream) throws ioexception {         imagedata  = ioutils.tobytearray(instream);         instream.close();     }       public synchronized void resize(int maxdimension) throws ioexception, imagereadexception, imagewriteexception {         // resize image if necessary         bufferedimage image = readimage(imagedata);         if (image.getwidth() > maxdimension || image.getheight() > maxdimension) {              // save existing metadata, if             tiffimagemetadata metadata = readexifmetadata(imagedata);             imagedata = null; // allow immediate gc              // resize              image = scalr.resize(image, maxdimension);              // rewrite resized image byte[]             byte[] resizeddata = writejpeg(image);             image = null; // allow immediate gc               // re-code resizeddata + metadata imagedata              if (metadata != null) {                 this.imagedata = writeexifmetadata(metadata, resizeddata);             } else {                 this.imagedata = resizeddata;             }         }     }      private tiffimagemetadata readexifmetadata(byte[] jpegdata) throws imagereadexception, ioexception {         iimagemetadata imagemetadata = imaging.getmetadata(jpegdata);         if (imagemetadata == null) {             return null;         }         jpegimagemetadata jpegmetadata = (jpegimagemetadata)imagemetadata;         tiffimagemetadata exif = jpegmetadata.getexif();         if (exif == null) {             return null;         }         return exif;     }       private byte[] writeexifmetadata(tiffimagemetadata metadata, byte[] jpegdata)                                  throws imagereadexception, imagewriteexception, ioexception {         bytearrayoutputstream out = new bytearrayoutputstream();         new exifrewriter().updateexifmetadatalossless(jpegdata, out, metadata.getoutputset());         out.close();         return out.tobytearray();     }       private bufferedimage readimage(byte[] data) throws ioexception {         return imageio.read(new bytearrayinputstream(data));     }      private byte[] writejpeg(bufferedimage image) throws ioexception {         bytearrayoutputstream jpegout = new bytearrayoutputstream();         imageio.write(image, "jpeg", jpegout);         jpegout.close();         return jpegout.tobytearray();     }      public synchronized void writejpeg(outputstream outstream) throws ioexception {         ioutils.write(imagedata,  outstream);      }      public synchronized byte[] getjpegdata() {         return imagedata;     }  }