question: public boolean rewriteExif ( ByteBuffer buf , Collection < ExifTag > tags ) throws IOException { ExifModifier mod = null ; try { mod = new ExifModifier ( buf , this ) ; for ( ExifTag t : tags ) { mod . modifyTag ( t ) ; } return mod . commit ( ) ; } catch ( ExifInvalidFormatException e ) { throw new IOException ( "Invalid exif format : " + e ) ; } }
target:  Attempts to do an in-place rewrite the exif metadata in a ByteBuffer for the given tags. If tags do not exist or do not have the same size as the existing exif tags, this method will fail.