final MessageDigest d = Constants.newMessageDigest();
final byte[] oeBytes = new byte[Constants.OBJECT_ID_LENGTH];
for (int i = 0; i < getObjectCount(); i++) {
final PackedObjectInfo oe = getObject(i);
oe.copyRawTo(oeBytes, 0);
d.update(oeBytes);
}
final String name = ObjectId.fromRaw(d.digest()).name();
final File packDir = new File(db.getDirectory(), "pack"); //$NON-NLS-1$