AssetFileDescriptor and FileDescriptor on Android

public static void copyRaw(AssetFileDescriptor fd, File destinationFile) throws IOException { FileChannel sourceChannel = new FileInputStream(fd.getFileDescriptor()).getChannel(); copyNIO( sourceChannel, destinationFile, fd.getStartOffset(), fd.getLength() ); } public static void copyNIO(FileChannel source, File destination, long startOffset, long length) throws IOException { FileChannel destinationChannel = null; try { destinationChannel = new FileOutputStream(destination).getChannel(); source.transferTo(startOffset, length, destinationChannel); } finally { // Tidy up... } }