private static Op toZooKeeperOp(ZooKeeperWatcher zkw, ZKUtilOp op)
throws UnsupportedOperationException {
if(op == null) return null;
if (op instanceof CreateAndFailSilent) {
CreateAndFailSilent cafs = (CreateAndFailSilent)op;
return Op.create(cafs.getPath(), cafs.getData(), createACL(zkw, cafs.getPath()),
CreateMode.PERSISTENT);
} else if (op instanceof DeleteNodeFailSilent) {
DeleteNodeFailSilent dnfs = (DeleteNodeFailSilent)op;
return Op.delete(dnfs.getPath(), -1);
} else if (op instanceof SetData) {